Aspects of Productivity of Traditionally Managed Barotse Cattle in the Western Province of Zambia

Aspects of productivity of traditionally managed Barotse cattle in the Western Province of Zambia

Ed van Klink

CENTRALE LANDBOUWCATALOGUS

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Aspects of productivity of traditionally managed Barotse cattle in the Western Province of Zambia

Proefschrift terverkrijgin gva nd egraa dva n doctor ind elandbouw -e nmilieuwetenschappe n opgeza gva nd eRecto rMagnificus , Dr.C.M .Karssen , inhe topenbaa r teverdedige n opwoensda g 2novembe r 1994o mvie ruu r ind eAul ava nd eLandbouwuniversitei t teWageningen .

i 2>(Sjögq BIBLIOTHEEK EXNDBOUWüNIVERSITK> WAGENINGEM Stellingen. 1. De invloed vand e leefomgeving enhe tmanagemen to pd e productiviteit vantraditionee l gehouden rundvee in Afrika isaanmerkelij k groterda ndi eva n chronische infectiesme t inwendigeparasieten .-Di tproefschrift - 2. Dea lo fnie tbestaand e relatietusse nveehouderi j en ecologische degradatie inonde rander eAfrik a vraagt eerder eengroter emat eva nbetrokkenhei d bij veeteeltontwikkeling danhe tveronachtzame n ervan.- Dit proefschrift- 3. Bij het vaststellen van ontwikkelingsdoelstellingen dient terdege rekening te worden gehouden met socio- economische aspecten, die als betrekkelijk vaststaande randvoorwaarden moeten worden gezien. -Dit proefschrift- 4. Routinematige bestrijding van teken in de traditionele veehouderij in Afrika is, zeker bij afwezigheid van de parasiet Theileria parva, veelal niet economisch verantwoord, en kan daarnaast een potentieel gevaar inhouden, door de ontwikkeling van premuniteit te blokkeren. -Pegram, R.G., A.D. James, O.P.M. Oosterwijk, K.J. Killorn, J. Lemche, M. Ghirotti, Z. Tekle, H.G.B. Cbizyuka, B.I. Mwase and F. Chizhuka (1991). Studies on the economie impact of ticks in Zambia. Exp. Appl. Acarol., 12:9-26.- 5. De verdere ontwikkeling van duurzame landbouw en veehouderij zou zeer gediend zijn met een eenduidige definitie van het begrip duurzaamheid, -symposium Duurzame Dierlijke Productie, Eisen vanuit markt, milieu en maatschappij. Studievereniging "De Veetelers", 29 Januari 1992, Ede- 6. Een bedrijfsvoering, die gericht is op het handhaven van een zo hoog mogelijk gezondheidsniveau, verhoogt de kwaliteit van de veehouderij. -Julicher, C.H.M., B.O.M. van Klink, G. de Peuter, D.L. Schumer, G.H.J.M. Versteijlen (1993). De Toekomst van de Diergezondheid. "Wie zal het een sorg zijn?!" Ministerie van Landbouw Natuurbeheer en Visserij, Den Haag- 7. Gezien het ontbreken van natuurlijk bos, het vrijwel ontbreken van vrij levend grootwild en de hoge veebezetting past Nederland bescheidenheid in de discussie over het kappen van tropisch regenwoud, de olifantenjacht en overbegrazing in de derde wereld. 8. Bijuitbrake nva nee nbelangrijk eVeewetziekt e worden doord esecto rveela lmee rd egenome nmaatregele n als debetreffend e ziekteal sproblee mervaren . 9. Omhe tbegri pgrondgebondenhei d ind e biologische veehouderijvor mt egeve n zullend eveehouderij ,he t daarvoor beschikbare voederareaal énhe t beschikbare areaal omd egeproduceerd emes t opa ft e zetten onderdeelui tmoete nmake nva néé ne nhetzelfd e systeem. 10. Hetdumpe nva ngoedkoo p Europeesvlee so pmarkte n in westAfrika ,waa rvoora lve evanui td eSahe lword t vermarkt, isnie t alleen eenbedreigin g voord e ontwikkeling vand ewelvaar tva nveehouder se nd e ontwikkeling vangerelateerd e activiteiten,maa rhoud t ookee nbedreigin g invoo rd epoginge nd e verwoestijning tebeperken .

11. Identificatie-e nregistratieregelinge n voordieren , primair opgezette nbehoev eva ndiergezondhei d en residutracering,diene n eenro lt espele ni n kwaliteitsbeheersings- engarantiesystemen ,med e omdat ditee npositie f effect zalhebbe n ophe tdraagvla k voor dezeregelingen . 12. Geenenkel eoverhei d isi nstaa td e 200jaa rvoorui t te ziendi e noodzakelijk zijno mtropisc hhardhou to p werkelijk duurzamewijz e teproducere n ent eoogsten . 13. Datee ngedeelt eva nd etheori ete naanzie nva n regulering vand evoedselopnam e vanKetelaar se n Tolkampmogelij k ooko pmense nva ntoepassin gka n zijn,val t onder anderea ft e leidenui the t feitda t babieshu n flesminde rve r leegdrinken,naarmat ed e speenminde rmakkelij kmel kdoorlaat .-Ketelaars , J.J.M.H., and B.J.Tolkam p (1991).Towar d aMa wTheor y of Peed Intake Regulation inRuminants .Ph.D .thesis , Landbouwuniversiteit Wageningen.- 14. Hetkusj e iswaarschijnlij k deenig e natuurlijke pijnbestrijdingswijzewaarva n zelfsdoo rd egrootst e bestrijdersva nkwakzalveri jd ecuratiev ewerkin g niet wordt betwijfeld. Stellingenbehorend ebi jhe tproefschrif t "Aspectso f productivity oftraditionall ymanage d Barotsecattl e inth e Western Province of Zambia",va nE dva nKlink ,2 novembe r 1994t eWageningen . Promotoren: Dr.D .Zwar t BuitengewoonHoogleraa rTropi&ch eVeehouderi j

Dr.J.P.T.M .Noordhuize n HoogleraarGezondheids -e nZiektelee r CIPDAT AKONINKLIJK EBIBLIOTHEEK ,DE NHAA G

Klink,E.G.M ,va n

Aspectso fproductivit yo ftraditionall ymanage dBarots e cattlei nth eWester nProvinc eo fZambi a/ E.G.M .va n Klink.- [S.l. :s.n. ] ThesisWageningen .- Wit hRef .- Wit hsummar y inDutch . ISBN90-5485-324- 7 Subjectheadings :cattl e ;traditiona lmanagemen t ;Zambi a /cattl e ;productivit y ;Zambi a Contents

CHAPTER 1. Generalintroduction . 1

1.1. Introduction. 3

1.2. Traditionallivestoc kkeepin gi nAfrica . 4

1.3. Livestockresearch . 7

1.4. Livestockdevelopmen tpolicies . 9

1.5. Cattlei nth eWester nProvinc eo fZambia . 15

1.6. Theai mo fth ethesis . 28

CHAPTER2 . Productivity study. 39

2.1. Herdmonitorin g intraditiona lcattl ehusbandr y ofWester nProvince ,Zambi aI :Organisationa l design,dat amanagement ,descriptiv easpects , andth eher dstructur eo ftria lherd si nfou r GrazingManagemen tSystems . 41

2.2. Herdmonitorin g intraditiona lcattl ehusbandr y ofWester nProvince ,Zambi aII :surviva lrate s ofcalves ,mortalit yan dslaughte rfigures ,an d salesfigures . 55

2.3. Herdmonitorin g intraditiona lcattl ehusbandr y ofWester nProvince ,Zambi aIII :reproductiv e performance,lactatio ninterval san dgrowth . 69

2.4. Herdmonitorin g intraditiona lcattl ehusbandr y ofWester nProvince ,Zambi aIV :ownershi po f animalsan dtransfer so fanimal sbetwee nherds . 87

CHAPTER3 . Internalparasit einfection san d

productivity. 101

3.1. Introduction. 103

3.2. Epidemiologicbackgroun do fliverfluk e infectionsi nAfrica . 104 3.3. Epidemiologiebackgroun do fintestina lparasit e infectionsi nAfrica . 109

3.4. Researcho ninfluenc eo finfection so n productivity. 114

3.5. Discussion. 123

CHAPTER4 . Interventionstudy . 133

4.1. Theus eo fa her dmonitorin gprogramm efo rth e evaluationo fth einfluenc eo fantiparasiti c treatmentso nth eproductivit yo ftraditionall y managedcattl ei nth eWester nProvinc eo f ZambiaI :intervention swit hTriclabendazol e andRafoxanide . 135

4.2. Theus eo fa her dmonitorin gprogramm efo rth e evaluationo fth einfluenc eo fantiparasiti c treatmentso nth eproductivit yo ftraditionall y managedcattl ei nth eWester nProvinc eo f ZambiaII :intervention swit hAvermectin ean d Thiabendazolean da combinatio no fRafoxanid e andThiabendazole . 151

4.3. Reviewingth eresult so fth einterventio n trials;reflection so nth estatistica ldemand s oftria ldesign ,feasibilit yan deconomi c consequenceso ftreatment . 165

CHAPTER5 . Generaldiscussion . 183

5.1. Theai mo fth ethesis . 185

5.2. Herdmanagemen t inrelatio nt oproductivity . 185

5.3. Environmental factorsi nrelatio nt o productivity. 190

5.4. Parasitesi nrelatio nt oproductivity . 193

5.5. Economican dsocio-economi caspect so fcattl e keeping inrelatio nt oproductivity . 195

5.6. Theusefulnes so flongitudina lher dmonitoring . 202

n 5.7. Conclusionsi nrelatio nt oproductivit yan d

livestockdevelopmen tan dperspectives . 202

Summary. 213

Samenvatting. 219

Acknowledgements/dankwoord. 225

CurriculumVitae . 227

in CHAPTER 1.

Introduction. 1.1. Introduction.

Inman yarea si nsub-Sahara nAfric ath ehuma npopulatio n growsconsiderabl y fastertha nth eagricultura lproduction . Thisresulte d ina ne tdecreas ei npe rcapit afoo dproductio n (Brumby,1986a ,Simpson ,1984) .Pritchar d (1988)reporte dtha t thedecreas ei sa shig ha son epercen tannually .A sa resul to f this,th eregio nbecome smor ean dmor edependen to nfoo d imports (Congresso fth eUS ,1984 ,ILCA ,1983 ,Worl dBank ,198 1 and 1984). Improvemento ffoo dsecurit yi stherefor ea primar y aimo fdevelopmen tactivitie s (Eicher,1982) .Eiche rals o stated,tha timprovemen to ffoo dsecurit yshoul dfocu so n agriculturalproductio na sa whole ,an dno to nth edevelopmen t ofcro phusbandr yalone .

Theconsumptio no fprotei ni sconsiderabl y loweri n developingcountrie stha ni ndevelope dcountries .I ndevelope d countries3 4% o fth econsume denergy ,an d5 6% o fth eprotei n originatesfro mlivestock ;i ndevelopin gcountrie sthes e figuresar e8 an d2 1% respectivel y (Reidan dWhite ,1980) . Jasiorowski (1975)indicated ,tha tth econsumptio no fanima l proteinstand sa t7 5gram spe rda ype rperso ni ndevelope d countries,wherea si ndevelopin gcountrie sthi si s5 grams . McDowell (1972)argued ,that ,i fattempt sar ebein gmad et o improveth eprotei nconten to fth efood ,i nman y instances peoplear eunlikel yt oaccep tne wtype so ffood .Ofte nthe yar e alreadyuse dto ,o rar ealread yusin glivestoc kan dlivestoc k products.Th eproductio no fanima lprotei ni sfa rbelo wlevel s anywhereels ei nth eworl d (Dwinger,1988) .Antene h (1984) showed,tha tth egrowt hi nmea tproductio ni sslowe rtha nth e growtho fth ehuma npopulation .Whil eth ehuma npopulatio n increasedb y2. 8% annually ,th emea tproductio n increasedb y 1.6 %pe rannum .Especiall y insouther nAfric athi sgrowt hha s declined.

Apartfro mreason so ffoo dquality ,livestoc kplay sa n importantrol ei narabl eagriculture ,whic hi sanothe rreaso n forspecifi cattentio nt olivestoc kdevelopmen t (Brumby, 1986b). Theprovisio no fdraugh tpowe ran dtranspor t isa n important inputi ncro phusbandr y (Anderson,1985 ,Aire yan d Buckland,1984 ,Gryseels ,1988 ,Gryseel san dAnderson ,1983 , Jahnke,1982 ,Matthewman , 1987).Th eus eo fanimal sfo r tractioni so nth eincreas ei nman ypart so fAfric a (Milimo, 1985, Munzinger,1982) .Manur ei sanothe rimportan tinpu t suppliedb ylivestoc k (Brumby,1986a ,Jahnke ,1982) .Powel lan d Mohammed-Saleem (1987)gav equantitativ einformatio no nth e importanceo flivestoc kfo rnitroge nan dphosphoru scycle so n cropland .Herd sof ,o naverage ,5 0animal swer ekraale do n cropland fortw ot othre econsecutiv enights .The ydeposited , dependingo nth eseason ,4 1t o10 4k go fNitroge nan d1 0t o1 5 kgo fPhosphoru spe rhectar epe rherd .

Inman yarea slivestoc kgraz elan dwhic hi sles ssuitabl e forcro pproduction ,thu sprovidin gth ebes tpossibl emean so f extractingvalu efro msuc hlan d (Aireyan dBuckland ,1984 ,Gow , 1987, Pritchard, 1988). Ineconomica lterms ,a sprovider so f finance (McDowell,1972) , livestocki sindispensabl e inman y areaso fAfrica .

Forth ereason smentione dhere ,livestoc kan dlivestoc k development isimportan ti nAfrica .Th estudie sdescribe di n thisthesi swer ecarrie dou ti nth eframewor ko fth eLivestoc k DevelopmentProjec ti nth eWester nProvinc eo fZambi a (DeRooi j andWood ,1990) .Th estudie sconcer nthemselve swit h productivity ofcattl ei nth etraditiona llivestoc kkeepin g systemo fth eWester nProvince .I norde rt oprovid einsigh ti n themeanin go fth enotio no ftraditiona llivestoc kkeeping ,i n thelivestoc kdevelopmen tapproache san di nresearc hint o productivity andinfluence so nproductivity ,a novervie wo f literatureo nthes easpect si sgiven .Thi sovervie wi saime da t providing argumentsfo rcarryin gou tproductivit y researchi n traditional livestockkeepin gsystem si nth efield ,i.e .i n (privatelyowned )herd stha tar erepresentativ e forth e livestockkeepin gpractice so fth efarme rpopulatio n forwho m theresult so fth eresearc har eintended .I ti sals oaime da t givingground sfo rdirectin gresearc ha tpracticall y applicable results.

1.2. Traditional livestockkeepin gi nAfrica .

1.2.1. General.

Ofth elivestoc ki nAfric a7 5t o8 0% i smaintaine dunde r traditionalmanagemen t (Brumbyan dTrail ,1986 ,Dicko ,1990) . Inth eWester nProvinc eo fZambia ,wher eth estudie so nwhic h thefollowin gchapter sreport ,hav ebee ncarrie dout ,th e cattleindustr yi sentirel ytraditional .

Traditionalmanagemen tgenerall y implies,tha thardl yany , orn oinput sar eintroduce d intoth esystem ,an dtha tcommuna l useo fgrazin gresource si sth erule .Th elivestoc kmanagemen t isgenerall yaime da tris kaversion ,rathe rtha na t commerciallyoptima lexploitatio no fth elivestoc k (DeLeeuw , 1990).Th evas tmajorit yo fth elivestoc ki skep ti nagro - pastoralsystems ,i nwhic hth elivestoc kproductio ni s integrated inth eoveral lfar mproductio n (Brumby,1986a , Brumbyan dTrail ,1986 ,Mclntir ean dGryseels ,1987) .Stric t pastoralism,i nwhic hth eowner sd ono tengag et oan yexten ti n agriculturalactivities ,i snumericall y lessimportan t(Gall , 1981).

1.2.2. Theimportanc eo flivestoc ki nth erura leconomy .

Owninglivestoc kgenerall ymeans ,tha tlarge rarea sca nb e cultivated,becaus eo fth eavailabilit yo fdraugh tpower .Als o theproductivit yo ffield sca nb eimprove dthroug hth eus eo f manure.Severa lauthor sargued ,tha tlivestoc kownin gfarmer s realisehighe ryield stha nthos ewh od ono tow nlivestoc k (Anteneh,1984 ,Brumby ,1986a ,Brumby , 1986b). Incas eo fa calamitysuc ha sdrought ,livestoc kma ycontribut eimportantl y toth eexten tth eowner sca ncop ewit hit .Campbel l (1984) illustrated this,b ycomparin g livestockowning ,strictl y pastoralMaasai ,settle dMaasai ,wh oengage d incro phusbandry , whileals oownin g livestock,an da people ,settle d inth esam e area,wh ocultivate d land,withou townin ganimals .Th esettle d Maasaiwer emos tsuccessfu l inovercomin gth esituation .

Livestockar efrequentl yth esourc eo fincom ei n situationswher ecro pproductio n ismainl y subsistenceoriente d (Eicher,1982 ,Crotty ,1980 ,ILCA ,1980 ,Jahnke ,1982 ,Jarvis , 1980, McDowell,1972 ,Schneider ,1984 ,Winroc kInt. ,1978) . ILCA (1982)showed ,tha tlivestoc ki sals oo fgrea timportanc e incommercia lsense .Th eestimate dannua lincom efro mlivestoc k inAfric awa si nth erang eo f1 0billio nUS $i nth eearl y eighties,o fwhic h5 0% wa sattribute dt odirec tanima l products (meat,milk ,skins ,fibre) .Th eres twa saccounte dfo r byservice san dnon-foo dproduct ssuc ha smanur ean dtraction . Gamean dfis haccounte d for3. 5billio nUS$ ,an dth egrai n outputwa svalue da t8. 5 billionUS$ .Masig a (1990)reporte da n annualcontributio no flivestoc kproductio nt ooveral l agriculturalproductio no f1 4billio nUS$ ,o fwhic h5 billio n areindirec tbenefits .

1.2.3. Constraintst olivestoc kproduction .

Livestockproductio n inAfric ai sdepresse da sa consequenceo fth evariabilit y infodde ravailabilit yan d quality(' tMannetje ,1981) .Thi si smainl ycause db yclimati c variation.I ntropica lregion sth eamoun to frainfal l isth e limiting factor,a soppose dt oth esituatio ni ntemperat e zones,wher etemperatur ei sth emai ninfluenc e (McDowell 1972). Dryperiod scaus ea considerabl ereductio ni nth equalit yan d quantityo fth efodde r (Mosie tal. , 1976),an dplac e considerablestres so nperformance ,suc ha sconceptio nan dmil k production (Chandler,1971) .

McDowell (1972)als omentione ddisease san dparasite sa s constraints.Holtzma n (1982)suggested ,tha treductio ni n productivity asa resul to fdisease sma yb ea shig ha s5 0o r6 0 %.Th enumber so fanimal sannuall ydyin go fanima ldisease sar e considerablea swell .ILRA D (1984)mentione da nestimate d5 0 millioncattl ean d10 0millio nsheep .Th eseasona lreductio ni n conditiona sa resul to fmalnutritio nma yb eo fimportanc ei n thesusceptibilit y fordisease san dparasite s (McDowell,1984) . TheAfrica ntrypanosomiasis ,transmitte db ytsets eflies , largelydetermine sth elivestoc kdistributio no nth econtinent , preventingth epossibl eus eo flarg earea so ffavourabl e pastures,an dhighl yinfluence sth eproductivit yo fanimal s keptwithi ntsets einfeste darea s (Jordan,1990) .

ThoughMcDowel l (1972)suggested ,tha tpressur eo fstoc k numberso nth elan dma yb ea constrain ttoo ,Jarvi san dErikso n (1986)foun d indications,a tleas tfo rsom especifi ccases , thatcattl enumber sincreased ,i nspit eo fwarning so f overstocking.The ysuggeste dtha tthi scast ssom edoub ta st o theseriousnes so fovergrazin g asa productivit yconstraint . Contraryt o"commo nbelief " (Harding,1968) ,severa lauthor s didno tagre et oth ethesis ,tha tlivestoc kar ea nimportan t causativeagen ti nth edesertificatio no flarg earea so fAfric a (Haaland,1979 ,McDowell ,1984) .Haalan dargued ,tha tcuttin g treest ofee diro nfurnace sha sbee na muc hmor eimportan t cause,an dtha tcroppin gha scontribute d aswell .Livestoc k should inthi scontex trathe rb esee na sth eultimate ,residua l userso fa range ,tha tallow sn oothe rus ean ymore .McDowel l suggested,tha tlivestoc kma yeve nhav eplaye da rol ei n slowingth edesertificatio nproces sdown .Animal sconsum ehar d podtre eseeds ,whic hbecom emor esensibl et omois tafte r passingthroug hth eruminan tdigestiv esystem .Th e "mainstream view"t oth eproble mo fdesertification ,a si twa sterme db y Sandford (1983),howeve rfalse ,di dcaus et osom eexten t disinterest inth ewellbein go flivestoc kkeepers .

1.3. Livestockresearch .

Extension,aime da timprovin g farmperformance ,ofte ndoe s notsee mt oattai nth erespons eexpected .I nman ycase sth e messagesar eno tadapte dt oth eloca lcircumstance s (Abalue t al.,1987 ,Biggs ,1980) .The yofte nd ono tfi ti nth eregula r farmingpractice s ina technica lsense .Furthermore ,i nman y casesexecutio no ftechnica lrecommendation si sno tpossibl e duet oinfluence so fnon-technical ,fo rexampl esociological , nature.Thoroug hknowledg eo fth eloca lsituatio ni stherefor e ofprim eimportanc e (Dickiean dO'Rourke ,1984) .Farmin g systemsresearc h (anddevelopment )aim sa tidentificatio no f farmers'needs ,an dformulatio no fresearc ho nth ebasi so f that.Thi sresearc hi saime da tincreasin gfarmer swelfare , especiallydirecte dtoward sth esmal lfarme rwit hfe wresource s (Normanan dGilbert ,1981 ,Shane re tal. , 1981). Interventions appliedofte nten dt oimprov eth ecas hpositio no fth efarmer , whileincreasin ghi sdependenc yo ninpu tan doutpu tmarket s (Bakere tal. ,1983 ,Norma ne tal. , 1982). Interdisciplinarity isa typica lcharacteristi co fthi styp eo fresearc h (Shanere t al.,1981 ,Sollo de tal. , 1984).Abass ae tal .(1987 )argued , thatimprovemen tefforts ,tacklin gseparat eproblems ,generat e lesssucces stha nthose ,usin ga nintegrate dapproach ,aime da t improvementso fmanagerial ,geneti can denvironmenta lnature . Behnke (1985)referre dt omeasurin gth eprofitabilit yo f livestockenterprises ,an dattemptin gt ocompar esubsistenc e andcommercia l livestockproduction .H eindicated ,tha t informationderive d frombiologica lmeasure so fher d productivity shouldb ecombine dwit heconomi cassessments ,an d withth eimpac to fth elivestoc kenterpris eo nth enutritiona l statuso fth epeopl eengage d init .

Thecomplexit yo fagro-pastoralis tan dpastoralis t structuresi nAfric amake si tdifficult ,i fno timpossible ,t o givea framewor kfo rdevelopment ,appropriat et oth ewhol e region (Little,1984) .Littl eargued ,tha tstud yo fspecifi c socio-economic indicatorsallow sfo rcompariso nbetwee n regions.Apar t fromsocio-economi c aspects,ecologica lzone s arelikewis eo fimportanc ei ncharacterisin gregiona l differences,an ddirectin gresearc happroache s (Jahnke,1982 , Abalue tal. ,1987 )an dresearc hprioritie s (Pratt,1984) .Th e ecologicalzone sa sdistinguishe db yJahnk e (1982)ar eth e arid,semi-arid ,sub-humi dan dhumi dzones .Th eclimat ei sth e determining factori ncharacterisin gth ezones .Sinc eda y lengthi smor eo rles suniform ,an dtemperatur ei sonl yo f importancea sa determinin g influencei fi ti sextreme ,i ti s predominantly rainfalltha tdetermine sth ezonation .I nth e arid zoneth eaverag eannua lrainfal li sles stha n50 0mm. ,i n thesemi-ari d zonei ti sbetwee n50 0an d100 0mm. ,i nth esub - humidzon ei ti sbetwee n100 0an d150 0mm .an di nth ehumi d zonei ti smor etha n150 0mm .Ther ei sa clos ecorrelatio n betweenlan dus ean drainfall ,an dtherefor eth ezonatio ni s alsoexpresse d interm so fth eaverag eannua lnumbe ro fgrowin g days.I nth eari dzon eles stha n9 0growin gday sar ecounted , inth esemi-ari d zone9 0t o180 ,i nth esub-humi d zone18 0t o 270an di nth ehumi dzon emor etha n270 .Th erang ei n ecologicalcondition si nsub-sahara nAfric ai sver ybroad ,an d obviouslyth eapproac han dprioritie si nresearc hwil ldiffe r betweenari dan dsemi-ari darea san dhumi dareas .

Notwithstandingth eclea rimportanc eo fintegrate d research,studie sint ospecifi caspect so fproductivit yd oo f coursetak eplace .Th eus eo fanima ldraugh tpower ,an dth e needt oexpan dth eus eo fanimal sfo rtractio nwa sdiscusse db y Anderson (1985)an dGryseel san dAnderso n (1983).Bot hauthor s discussedth epossibilitie so fusin gcrossbre ddair ycow sfo r traction.Matthewma n (1987)gav ea novervie w ofth eliteratur e onth eus eo fcow sfo ranima ltraction .Generall yoxe nar e preferredbecaus eo fthei rbigge rsize ,bu ti nsituation swher e lando rfodde rresource sar ea limitin gfactor ,cow sar e frequentlyused .

Animalnutrition ,an despeciall yth equalit yan d possibilitieso fth enatura lrang ean dits 'influence so n productivity areimportan tsubject so fspecifi cresearc ha s well (Coppocke tal. ,1986 ,' tMannetje ,1981 ,Mos ie tal. , 1976).Jenning san dHolme s (1985)studie dth eus eo f supplementary feedsi ndair yenterprise so ntropica lpasture s inth ecommercia lsector .Th eus eo fNo nProtei nNitroge nlick s andth eeffec to fbus hclearin go nth equalit yo fth epastur e wasdescribe db yPratche t (1983).Improvemen to fth erang ewa s alsoa subjec to fVerboo m (1965an d 1966).

Aspectso fproductivit yo fpastora lsystem swer estudie d byCossin s (1985)an dPotte r (1979).Cossin sshowed ,tha tth e Boranapastora lsyste mproduce snearl yfou rtime sa smuc h protein,an dsi xtime sa smuc hfoo denerg ype rhectar etha n climatically comparableAustralia ncommercia lranches .Potte r demonstratedth eeffec to fstockin grat eo nlif eweigh tgain , peranima la swel la spe rhectare .H eshowe dtha tth eweigh t gainpe ranima ldecreases ,bu tth etota lweigh tgai npe r hectareincrease sconsiderably ,whe nth estockin grat ei s increased.H eargued ,tha tlan di sa mor eimportan tproductio n unittha nth eindividua lanimal .Traor ean dWilso n (1988) discussedth einfluenc eo fth eenvironmen tan do fpathologica l factorso nmortalit yan dmorbidit y inruminant si nMali ,an d Wilson (1985)studie dreproductiv easpect so fth eproductivit y ofsedentar ycattl ei nth esam eregion .Bot hpublication s reporta nimportan tinfluenc eo fth enutritiona lstatu san dth e seasono nproductivity . Socio-economic factorsar eofte nmentione da ske y determinantsi nman ydevelopmen trelate dresearc hactivities . Ownership,processe so fdecision-makin g andrevenu e distribution,an dth epositio no flivestoc kan dlivestoc k ownersi nsociet ydetermin et oa considerabl eexten tth e abilityo flivestoc kowner st ofollo wrecommendation s (Little, 1984,Ariza-Nin oan dShapiro ,1984 ,Crotty ,1980 ,Jarvis , 1980).

1.3.1. Livestockproductivit yresearc hi nth esouther n Africansubregion .

Mucho fth eresearc hint olivestoc kproductivit y inth e regionha sbee ndirecte dt ocomparin ga variet yo floca lcattl e breedswit heac hother ,o rwit himporte dbreeds .Subject so f thesecomparison swer etrait ssuc ha scalvin gpercentage , weaningpercentag ean dmortalit y (Hetzel,1988 ,Tawonezvi , 1984).Mos to fth ecattl ebreed so fsouther nAfric abelon gt o thegrou po fth eSang abreed s (Masonan dMaule ,1960 ,Epstein , 1971),animal stha tusuall yhav ea smal lcervica lhump .Apar t fromth eBarots eo fWester nProvince ,th eTswana ,Tuli , Afrikander,Mashona ,Tong aan dNkon ebelon gt othi sgroup .Mos t ofth ecomparison sar edon eunde rrelativel ycontrolle dfar m situations,an dofte na ta highe rleve lo fmanagemen ttha n normallyexperience d (Thorpee tal. ,1980a ,1980b ,1981 ,Anima l ProductionResearc hUnit ,1981 ,Anima lProductivit yResearc h Team,1969 ,1971) .Som eresult so fthes ecomparativ e productivity studiesar egive ni ntabl e1 .I ngenera lth e indigenousbreed sreac t favourablyt oimprovement so fth e management,i nterm so fproductivity .Unde rrelativel yoptima l conditions,importe dbreed sten dt operfor mbetter .Th eloca l breedscop ebette rwit hles sfavourabl ecircumstances ,althoug h theyd oexperienc eth einfluenc eo fth eenvironmen t (Block, 1958).

Someresearc h intoth epotentia lo findigenou scattl efo r milkproductio nwa sdon eb yWalke r (1962).Fou rbreed s originating fromZambi awer ecompare d forduratio no flactatio n periodan dmil kyield .Th eAngon ian dTong aproduce d 758an d 636litre spe rlactatio no f29 0days .Th eBarots ean dLundaz i produced 1046an d106 8litre si n30 2an d30 5day srespectively .

1.4. Livestockdevelopmen tpolicies .

Thenecessit yo fagricultura ldevelopmen t inAfric aha s alreadybee nexplained .Progres si nth eagricultura l sectori s notonl yo fimportanc efo rth eimprovemen to fth efoo d Table 1. Results of various comparative studies into the productivity of indiginous Sanga and Zebu cattle breeds of the Southern African subregion. (Source (mainly): overview given by Hetzel, 1988).

breed calving birth preweaning weaning weaning rate weight mortality rate weight (%) (kg) (%) (%) (kg) * Zambia:Anima l ProductivityResearc hTea m (1969,1971 )

Africander 71 5.1 67 1721

Mashona 83 3.7 80 151 Angoni 85 4.1 81 150

Zambia:Thorp ee tal .(1980a ,1980b )

Barotse 78 26 5.3 74 1672 Boran 75 25 8.3 69 170 Angoni 83 23 2.7 80 147 ** Zambia:Thorp ee tal .(1981 )

Africander 54 31 5.1 51 1743 Barotse 58 27 6.6 54 163 Boran 66 27 2.3 65 169 Angoni 69 24 6.4 65 149

Botswana:Anima lProductio nResearc hUni t( 1981)*

Africander 68 8 62 1744 Tswana 80 6 75 179 Tuli 87 5 82 176 Bonsmara 83 11 74 204 Brahman 72 13 63 184

Zimbabwe:Tawonezv i (1984)

Africander 56 16.7 46 1845 Tuli 70 8.8 64 184

Mashona 76 10.9 68 172 Nkone 63 11.7 56 187 Brahman 70 17.5 58 207

weaning age 6.7 months weaning age 7.5 months weaning age 8 months weaning age 7 months weaning age 8.5 months

tt environment termed high performance by Hetzel (1980) environment termed low performance by Hetzel (1980)

10 availability andsecurity .Mello r (1986)argued ,tha t developmento fth eagricultura l sectorlead st oincrease d employmentan dexpandin gincomes ,o fwhic hgenerall y6 0t o8 0% isspen to nfoodstuffs .I nitsel fthi sstimulate sth e agriculturaldevelopment ,whil ecausin ga spill-ove reffec tt o othersector so fth eeconomy .Simpso n (1984)argued ,tha ti n thesmal lfar mo rsubsistenc esector ,o fwhic hth emajorit yo f casesi sagro-pastora lb ynature ,developmen t isneede dt omak e moreefficien tus eo favailabl eresources ,an dt oincreas e commercialisation.Researc hi npastora lsystem sshows ,tha ti n generalpastoralist sar emostl ywel ladapte dt oth e difficultieso fthei renvironmen t (DeLeeu wan dKonandreas , 1982, Cossins,1985) . Ifproductivit y isexpresse d interm so f biomass (kgliv eweight/hectare) ,th eofftak ei si nth erang e of1 6t o2 8% o fth etota lamoun to fliveweigh tpe rhectar e present (DeLeeu wan dKonandreas ,1982) .D eLeeu wan d Konandreasterme dthi squit eefficient .

Inth epast ,livestoc kdevelopmen tproject swer eofte n aimeda tincreasin gth ebul ko fth eproductivity .The ywer e aimeda tmeetin gdemand so f (predominantly)th eurba n population,throug hlarg escal eschemes .Introductio no fhighl y productivebreed sfo rimmediat eutilisatio no rcrossbreedin g wasofte npar to fthes eefforts ,mostl y inth edair ysecto r (Gregorye tal. ,1982 ,Trail ,1981) .Th eobjective so fth e livestockowners ,sometime sconflictin gwit hthi sgenera lgoal , wereofte noverlooke d (Atherton,1984) .A tpresent ,th e developmento fth epossibilitie so fth eproducer si sth emai n areao finterest .A tth esam etim ei ti sattempte dt obalanc e theseinterest swit hmeetin gnationa leconomi cgoal s(Atherton , 1984).Th eNationa lBee fScheme ,initiate d inth eseventie si n Zambia,i son esuc hexampl e (ThirdNationa lDevelopmen tPla n 1978-83, 1979). Itaime da tincreasin gth eavailabilit yo fbee f onurba nmarkets ,throug hth eestablishmen to frura lCattl e DevelopmentAre aprogrammes .

Livestockdevelopmen tpolicie shav ei ngenera ltw omai n objectives:increase danima lproduction ,o rrather ,increase d animaloutpu tan drangelan dconservatio n (Lawrye tal. , 1984). Sinceth elarge rpar to fAfrica ncattl ei nth etraditiona l sectori smaintaine do nfragil eland s (Bremere tal. ,1984 )th e developmento fthi ssecto ri sa comple xmatter .A holisti c projectapproac han dcoordinatio no factivitie sbetwee n developmentagencie si simportan t (Gow,1987) .Va nRootselaa r andWoo d (1990)emphasise dth eimportanc eo fmakin glan dus e planningpar to flivestoc kdevelopmen tpolicies .

11 Specificexample so fattempt st oorganis eth erang elan d managementar eth eGrazin gCell si nBotswan a (Sweet,1987 )an d theGrou pRanche si nKeny a (Oxby,1982 ,Peacock ,1987) .Th e GrazingCell sa sthe ywer eoperate d inBotswan aha dtw omai n objectives:

- toprovid ea practica ldemonstratio no fimprove drang e conditionan dcattl eperformanc ethroug hgrazin g managementan dstoc kcontrol , toenabl ecomprehensiv eevaluatio no fdifferen tgrazin g systemsfo rrehabilitatio no fdegrade dland .

Acel lwoul dmeasur e3 b y3 kilometres ,an dwa ssuppose dt ob e stockedwit h15 0weaner sannually ,preferabl ysteers ,whic h weresuppose dt ob ekep ti nth ecell sfo r2 years .I nth eGrou p Ranchesprogramm ea specifi care awa sdemarcate dan dassigne d togroup so fpeopl e (Maasai),wh ower ethe nlegall yth esol e userso fth erange .Th emai ndifferenc ewit hcommonl yknow n ranchesis ,tha tno ta nindividua lhold slega lright st oth e land,bu tth egroup .Grazin gblock sar eals oa wa yo f organisingth eus eo fgrazin gland ,bu twithou ttransferrin g legalownershi pright so fth elan dt oth eusers .Th efac ttha t noright sar etransferre d distinguishesth egrazin gblock sfro m thegrou pranche s (Oxby,1982) .

Peacock (1987)describe dth eimpac to fth eGrou pRanche s schemeo ntraditiona lpowe rstructures .A sa resul to fth e initialreductio no fth einfluenc eo fth etriba lhierarchy , individuallivestoc kowner stoo kadvantag eo fth erelativ e "anarchy".The ydisregarde dth erang emanagemen tdecision sfo r whichpurpos eth eschem ewa sse tup ,grazin gthei ranimal s whereeverthe ypleased .Afte ra perio dth egrou preverte dt o thetraditiona l structureso fauthority ,whic hseeme dt o improveth esituation .Peacoc kargued ,tha tthes eproblem s couldhav ebee nforesee nan dprevente d ifa thoroug hknowledg e ofth etraditiona l systemwa sacquire dfirst .

Sweet (1987)als odescribe ddifficultie si nth eexecutio n ofth eGrazin gCel lscheme .Farmer swer eno tparticularl y interested.Th emai ncause swere ,tha tfencin gof fpiece so f landan dgivin gthe mt ojus ta fe windividual st ous ei na n alreadyovercrowde d area,wa sno texactl ypopular .Als oth e cooperativeorganisatio nwa srelativel yalie nt oth eusers .Th e potentialbeneficiarie sdi dno tse eenoug hadvantage .

Invariou sarea si nth eSahe lzon erang eenclosur etoo k placea sa nindividua linitiative ,i nrespons et oincrease d

12 pressureo nlan d (Behnke,1986) .I nSuda ni twa sdon et o protectgrasslan d forfodde rproductio n forth emarket .I n anotherare ai nSuda ni twa sdon et oprotec tpar to fth e grazingrang eagains ttransien tnomadi clivestoc kfo rdr y seasonuse .I nSomali afencin gof fstarte dwhe nfarmer s anticipated landshortage sdu et olivestoc kinfluxe sa sa resulto fth eintroductio no fboreholes .I nal lcases ,farmer s whodi dno tinitiall yparticipate ,foun dthemselve si nsever e landshortages .Livestoc kdevelopmen tpolicie sshoul dtak enot e ofwha ti salread yhappening ,i norde rt ob eabl et o streamline,rathe rtha ncounterac tevents .

BothPeacoc k (1987)an dSwee t (1987)emphasize d strongly thenecessit yt ostud yloca lstructure san dsituation s carefully,befor eplannin gactivities .I ti snecessar yt omak e suretha tintervention sar eno tconflictin gwit hinterest san d structureso fimportanc et oth etarge tgroup .Som efor mo f grazingrang econtro lis ,however ,deeme dnecessary .Lawr ye t al. (1984)furthe rargued ,tha tcommuna llan dus ei nsom efor m shouldb emaintained .Th eherd sar egenerall yto osmal lt ofor m aviabl eeconomi cuni to nindividuall yowne dranches ,whil e ecologically soundmanagemen tmeasure srequir ea considerabl e areao nwhic ht opla ngrazing .Developmen tprogramme sshoul d concernthemselve swit hth eestablishmen to finstitution sa t variouslevel st ocontro lth eus eo fth ecommuna lrange .

Dickiean dO'Rourk e (1984),discusse dthre emai n constraintst orang elivestoc kdevelopment ,o fecological , political/economic andsocia lnature .The yals oemphasize dth e need forrang emanagemen tadvisor st ob ever ywel lawar eo f localsituation san dstructures ,an dt oinclud euse rgroup sa s participantsi nplanning ,implementatio nan devaluatio no f projects.Go w (1987)stated ,tha tnationa lgovernment sshoul d alsob ecommitte dt olivestoc kdevelopmen t inth eextensiv e traditionalsector .

Thedamag edon et oth elivestoc kindustr yi nAfric aa sa resulto fanima ldisease san dparasite si sconsiderabl e (Holtzman,1982 ,ILRAD ,1984) . Increasingth eoutpu tcoul d thereforestar twit hreducin glosse sa sa resul to fdisease , through improvements inth eveterinar ycar e (Pritchard, 1988). Asfa ra simportan tepizooti cdiseases ,suc ha srinderpest ,ar e concerned,considerabl eeffort shav ebee nmad ei nth epas t (De Haanan dNissen ,1985) .However ,a sD eHaa ne nNisse npointe d out, theeconomi cdifficultie so fman yo fth egovernment si n Africabea rth edange ri nthem ,tha tachievement so fth epas t arelost ,becaus eth enecessar ycos to fth eveterinar y services

13 canno tb eborn ean ymore .ILC A (1988)described ,tha ti nal l 22countries ,i nwhic hi tcarrie sou t its'programmes ,th e livestockservice sar eentirel y financedfro mcentra l government funds.Especiall y sinceth eoi lcrisi so fth eearl y seventiesthi sha scause d increasingproblems .Masig a (1990) mentionedpoo rpolic yan dinadequat ebudgetin ga scontributin g causest oth edeclin ei nth estandar do fth eveterinar ycare . Staffexpenditur eha srise ni nspit eo fth ebudgetar ysetbacks , atth ecos to foperationa lexpenditure .A reorganisatio no f veterinaryan dlivestoc kservice si stherefor ehighl yrequired , introducingcos trecover ymeasure san dinvolvin gth eprivat e sector (DeHaa nan dNissen ,1985 ,D eRooi jan dWood , 1990).I n thecontex to fth ePa nAfrica nRinderpes tCampaign ,starte di n 1986, improvementsi nth eperformanc ean defficienc yo fth e veterinary servicesinvolve d inth erinderpes teradicatio n effortar etherefor econsidere dke yobjective si nth eprojec t (Taylor,1990) .

Epidemiological assessmentsan dth eeconomi cevaluation s ofbot hth edisease san dthei rmean so fcontro l (Putte tal. , 1987)shoul dguid eth edevelopmen to flivestoc khealt h provision.Thi sshoul db ebot hcos teffective ,an deffectivel y improvingth ediseas esituation .System so fdiseas e surveillancean dsubsequen tactio nar emor ecos teffectiv etha n thepreviousl yadvocate dmas svaccinatio ncampaigns .The yals o havea positiv einfluenc eo nth eveterinar y infrastructure (Zessinan dCarpenter ,1985) .Simplificatio no fveterinar y techniques,reducin gth ecos to fequipmen tan dequipmen t maintenance,reducin gth eris ko ffailur ecoul dpla ya rol ea s well.Th eus eo fVaccini aviru sa sa carrie ro frinderpes t vaccinei son esuc hexampl e (Pritcharde tal. , 1985).Th e provisiono fveterinar y servicesi sgenerall yver ywel l acceptedb ylivestoc kproducer s (Aronson,1981) .A ssuc hi ti s agoo dentr yfo ra napproac ht odevelopmen t inwhic hth e responsibility forimprovement s inth eanima lhealt hprovisio n lieswit hth eowner sthemselves .Sollo de tal . (1984)use dth e phrase "VeterinaryAnthropology " fora napproac ht olivestoc k researchan ddevelopment ,whic hi sproble moriente dan dwhic h triest ointegrat ecomponen t findingso fecological ,biologica l andsocia lnature .

Veterinarymeasure shav ea positiv einfluenc eo nth e productivityo fth elivestoc ki nAfrica .Becaus eo fthis ,an d invie wo fth eecologica lthreat san dth e (alleged)rol eo f livestocki nthi srespect ,increasin goutpu ta sa nobjectiv eo f livestockdevelopmen teffort si sa mor eappropriat ephras etha n increasingproductio npe rs e (Lawrye tal. , 1984).Livestoc k

14 managementdecisions ,aime da tris kaversion ,a si scommo ni n mosto fth etraditiona l livestockmanagemen tsystem si nAfric a (DeLeeuw ,1990) ,resul ti na productivit y approachwhic hi s moreo rles scomplementar yt ocommercia lranching ,i nwhic h production forth emarke ti sth emai naim .I frisk sar e reduced,th efarmer sma yb emor ewillin gt osel lanimals .Thi s implies,tha twhe nproductivit y isimproved ,offtak eshal lhav e tofollo wsuit .A sMatthewma n (1980)described ,farmer swil l readilyreac tt ocommercialisatio nefforts ,i funcertaint yan d diseaserisk sar eminimised .Th estructur eo fth emarketin g operation itselfinfluence scommercialisatio no fbot hth e cattletrad ean dth esociety .Thi si sillustrate db yth e auctionyar dsystem soperate d inKenya .No tonl yth efarmer s sellthei ranimals ,bu ttrader so fal lkind smak eus eo fth e opportunityt odispla yan dsel lthei rgood s (Aireyan d Buckland, 1984).Marketin gaspect sar eo fprim eimportanc ei n thedesig no flivestoc kdevelopmen tpolicies .

1.5. Cattlei nth eWester nProvinc eo fZambia .

Zambiai sa landlocke dcountr yi nsouther ncentra lAfrica . Figure1 show sa sketc hma po fth econtinen twit hZambi a outlinedo nit .Th eisoline so fgrowin gday si nth esouther n Africansubregio nar eals oindicate d (Jahnke,1982) .A sca nb e seen,Zambi ai sfo rth elarge rpar tlocate dbetwee nth e18 0an d 90day sisolines ,whic hmeans ,tha to naverag eth ecountr y experiencesbetwee n9 0an d18 0vegetatio ngrowin gday spe r year,termin gi tsemi-ari do nth eschedul egive nb yJahnk e (1982).

Onth ema pi nfigur e2 som egeographi ccharacteristic so f theWester nProvinc ear eindicated ,a swel la sth esituatio no f theprovinc eo nth ema po fZambia .I nth ewes tth eprovinc e borderso nAngola ,i nth esout ho nth eNamibia nCapriv iStrip . Theprovinc eshare sborder swit hth eNort hWester nProvinc ei n thenorth ,an dwit hth eCentra lan dSouther nProvince si nth e east (Resourceatla sfo rZambia ,1985) .

Thema pi nfigur e3 show sth eapproximat edelimitation so f theBarots efloodplai nan do fth eSeshek efloodplai nan d Machileflats .Thes earea sar eessentia la sseasona lgrazin g groundsfo rtranshuman tcattl e (Resourceatla sfo rZambia , 1985).Th eapproximat eexten to fth etsets einfestatio ni sals o indicated (Cortene tal. , 1988).Sinc etsets econtro leffort s arecurrentl ybein gundertake n inth ewester npar to fth e tsetseinfeste darea ,th epresen tsituatio nma yno tb eentirel y reflected.

15 Figure1 . Sketchma po fth eAfrica ncontinen t indicatingth e outlineo fZambia ,th eisoline so fgrowin gday s(90 , 180an d27 0growin gday spe ryear )an dth ehighlan d areasi nth esouther nAfrica nsubregio n(Jahnke , 1982).

Isolinaao fgrowin gday s inth asouttiar aAfrica n subragion

Highlands inth alouthar n Africansubragio n

16 Figure2 . Themai ngeographi c featureso fth eWester nprovinc e ofZambi a (source:Resourc eatla so fZambia , Longman).

17 TheWester nProvinc eo fZambi ai sfo rth elarge rpar t coveredwit hsavanna hwoodland ,intersperse dwit hgrass y depressionswithou ttrees ,th es ocalle ddambo's ,an drive r valleysan dplains .O fth eplain sth efloodplai no fth eZambez i river,o rBarots eplain ,i sth ebigges tan dmos timportant .Th e soilsconsis tpredominantl yo fpermeable ,relativel y infertile Kalaharisand s (Trapnellan dClothier ,1957 ,Verboo man dBrunt , 1970).Wit hth eexceptio no fth enorth-easter ndistric tKaoma , theprovinc eha slimite dsuitabilit y forcro pcultivation .Th e possibilities forextensiv elivestoc kkeepin gar equit egood . Duet oth epermeabilit yo fth eto psoils ,ther ei slittl e dangertha ttramplin go fth evegetatio nresult si nirreparabl e damage,an dth erisk so ferosio nar erelativel ysmal l(Va n Gils, 1989).

Theprovinc ei sinhabite db yth eLoz ian da numbe ro f smaller,affiliate dtribes ;henc eth enam eBulozi ,o r Barotseland (Barotsebein gth eTswan awor dfo rBuloz i(Prins , 1979)), underwhic hth eprovinc ewa sknow nbefor eindependenc e (Gluckman,1941 ,Hermitte ,1974) .Cattl ekeepin gha sbee na practice inth eprovinc efo ra considerabl eperio d (Roberts, 1976, VanHorn ,1977) .A sprovider so fmanur ean danima l tractionth ecattl eha sbee nindispensabl ei nth emixe dfarmin g systemo fth eprovinc e (Puzo,1977 ,Peters ,1960) .Especiall y sinceth esecon dhal fo fth e19t hcentur yth eimportanc eo f cattlefo rth eprovisio no fdraugh tpowe rha sincrease d (Kimmagean dWood ,1988) .Th eLoz ihav ea quit ewel l established chieftainshipwit ha centralise dpowe rstructure , ofwhic hth eKing ,o rLitunga ,i sth ecentra lperso n (Mainga Bull, 1973).Thi spowe rstructur eha st oa larg eexten t survivedth ecolonia lera ,a sa resul to fth efac ttha t Barotselandha sbee na Britis hprotectorat efro mth elat e19t h centuryuntil lindependence ,an dno ta forma lcolon y (VanHorn , 1977).Cattl ehav elon gbee nmostl y inpossessio no fth e nobility.Especiall ysinc eth eintroductio no fmigran tlabou r andth esubsequen tadoptio no fa partl ymonetar yeconomy ,mor e andmor ecommoner sals oacquire d cattle (DeRooi jan dWood , 1990).

Thelivestoc kpopulatio nvirtuall yentirel yconsist so f cattle.A tpresen tth ecattl epopulatio napproximate s500,000 , whileth egoa tpopulatio no fth eprovinc estand sa tabou t6700 . Therear earoun d370 0pig si nth eprovinc ean dth enumbe ro f poultry isapproximatel y 210,000 (VanKlin ke tal. ,1990a , DVTCS,Wester nProvince ,1990) .Th eapproximat edistributio no f thecattl epopulatio ni sshow ni nth ema po ffigur e4 .Cattl e isconsidere do fprim eimportanc efo rth efollowin greason s(i n

18 Figure3 . Mapo fth eWester nProvinc eo fZambia , indicatingth e extento fth eBarots ean dSeshek efloodplains ,an d theapproximat eboundarie so fth eTsets einfeste d area (Cortene t al., 1988).

International boundary Provincial boundary Zimbizi rivar Approx. ixtmt of Tuti •C^vvs^ infestation Barotaa floodplain

Suhika floodplai n and Machila flats

19 ordero fimportance) :

- agriculturalus e (manure,draugh t power), security (topa ydebts ,o rt ob euse d incas eo fa n immediatecas hrequirement) , - food (meat,milk) , - investments (storeo fwealth ,reserv efo rol dage) , forsocia lpurpose s (brideprice,gifts ,ceremonies ) (Beerling, 1991).

Finesar eon efor mo fdebt sfo rwhic hcattl ei softe nuse d (Gluckman,1955) .Th elivestoc ki sgenerall yprivatel yowned , andherde dtogethe rwit hth eanimal so fothe rowners ,unde rth e supervisiono fa herdkeepe r (Dicko,1990 ,Beerling , 1986).

TheWester nProvinc ei sconsidere da quarantin eare a againstth eintroductio no fContagiou sBovin ePleuropneumonia . Thisimplies ,tha ta buffe rzon ei smaintaine d alongth e westernborde rwit hAngola ,separate db ya cordo nlin efro mth e resto fth eprovince .Acros sthi slin eth etranspor to fcattl e isseverel yrestricted ,whil estringen tregulation s forth e exporto fcattl eou to fth eprovinc ear eals oi nforc e(Wood , 1983).

VanHor n (1977)identifie d factorstha tcause da declin e inth eagricultura lproductio ni nBarotseland .A nimportan t influencewas ,an dprobabl y is,th elabou rmigratio nt oth e SouthAfrica nmines ,and ,later ,t oth emine si nZambi ao nth e Copperbelt.Th erelativ elabou rdefici tresultin gfro mthi s reducedth eworkabl esiz eo fexistin g fields,an dth e possibilitieso fmovin g intoan dpreparin gne wfields .A tth e sametim elabou rmigratio nopene dpossibilitie st obuy ,rathe r thangro wth efoo drequired ,becaus eo fth eincreasin gus eo f money.Th eseriou seconomi c situationi nwhic hZambi afind s itselfa tpresen tcause sa decreas ei nth edependabilit yo n salaries,throug hth ehig hinflatio nrat ean dth ereductio no n foodsubsidies .Highe rdependenc eo ncro pproductio n forhom e consumption,requirin gmanur ean ddraugh tpower ,an dth enee d fora cas hsourc eincreas eth eeconomi c importanceo fcattle .

1.5.1. Productiontraits .

Thecattl eo fth eWester nProvinc ear eBarotse ,whic hi sa Sangabree d (Epstein,1971) .Th eanimal sar elarge ,wit hheav y bones,an dlyr eshaped ,spreadin ghorn so f6 0t o7 0cm .length . Theheigh ta tth ewither saverage d 137cm .fo r3 yea rol d males,an d12 9fo r3 yea rol dfemale sa tMazabuk aResearc h

20 Figure4 . Thedistributio no fth ecattl epopulatio no fth e WesternProvince ,Zambia ,a sfoun di nth e198 9Annua l LivestockCensus .

K-

21 Stationi nth eSouther nProvinc eo fZambia .Unde rnorma lrang e conditionsth eadul tbull sca nweig haroun d 580kgs. ,an dth e adultfemale saroun d40 0kgs. ;unde rimprove drang econdition s thiscoul dincreas et o63 0an d45 5respectively ,whil eo n Europeanfarm si nth eSouther nProvinc eweight so f71 0an d48 5 kgs. respectivelywer efound .The yhav ea small ,an di nfemale s virtually absent,cervico-thoraci c hump,an da moderatel y developeddewlap .Mos tcommo ncolour sar ebrown ,black ,dar k redan dfaw n (Masonan dMaule , 1960).

Barotsecattl ear equit ereasonabl emea tproducers .Maso n andMaul e (1960)reporte da dail yweigh tgai no f1.3 1 kgs.i n youngsteer si na particula rtrial ,don ei nMazabuka . Cruickshanke tal . (1976)carrie dou tfeedin gtrial si nwhic h Barotsesteer sreceive d foodsupplement sdurin g12 0days , resulting ina 1 9% increas ei nbee fcarcas sproduction .Th e milkpotentia lo fth ebree dfo rcommercia lpurpose si s moderate.Walke r (1962)foun da productio no faroun d100 0 litresi n30 0days .Unde rnorma lcondition si nth eWester n Provincehoweve rth eproductio n forhuma nconsumptio n isno t moretha napproximatel y 1litr epe rda y (Lutke-Entrup,1971) . Besselan dDaply n (1977)foun da mil kproductio no faroun d12 2 litrespe rlactation .

Apartfro mresearch ,i nwhic hth eproductivit yo fth e Barotsei scompare dwit hothe rSang aan dZeb ubreed s (Thorpee t al., 1980a,1980b ,1981 ,Walker ,1962 ,Hetzel ,1988 )unde r "improved"rang emanagemen tconditions ,som eresearc hi nth e traditional sectorha sbee ndone ,i nwhic heithe rattentio nwa s givent oth eproductivit yo fth eBarots ea swel la st otha to f otherbreed s (Besselan dDaplyn ,1977 ,Perr ye tal. , 1984),o r inwhic hth eproductivit yo fth eBarots ewa sspecificall y studied (Abraham,1979 ,Lutke-Entrup ,1971) .Tabl e2 show ssom e ofth eresult so fstudie si nth etraditiona l sector,fo rth e Barotsebreed .Matthewma n (1980),reportin go nresearc hi n severalarea so ftraditiona lcattl ekeeping ,devote dsom e discussiont oth eeffect stha timprovement so fproductivit yi n thetraditiona l sector,predominantl ythroug himprovement si n theveterinar ycare ,woul dhav eo nth eoutput .Matthewma nan d Perry (1985)gave ,o nth ebasi so fproductivit yparameter s studied ina numbe ro flocation si nZambia ,indication so nho w tous eth eher dstructur ea sa nindicato ro fproductivity . Researcho ngrazin gan drang elan dimprovemen twa sreporte db y Kulich (1976).

22 1.5.2. TheDepartmen to fVeterinar yan dTsets eContro l Servicesan dth eLivestoc kDevelopmen tProjec t WesternProvince .

Afterindependence ,th egovernmen to fZambi aestablishe d freeveterinar yservice sfo rlivestoc kowners ,a sa contributiont oth edevelopmen to fth etraditiona l livestock farmingsystems .Th eorganisatio no fth eDepartment ,a si nman y otherAfrica ncountrie s (Masiga,1990) ,ha sa pyramida l structure:veterinar yassistant sa sfiel dworkers ,unde rth e supervisiono fDistric tVeterinar yOfficers ,wh oi nthei rtur n areresponsibl et oth eProvincia lVeterinar yOfficer .Th ehea d ofth eDepartmen t isth eDirector .Th edistributio no fcattl e postsan dcrushpen si nth eWester nProvince ,whic har ei n principleth e"extensio nan dtreatmen tunits "fo rth e veterinaryassistants ,i sshow no nth ema pi nfigur e5 .

Asi nman ypart so fAfrica ,th eadequac yo fth eservice s renderedha sdecline da sa resul to fth eeconomi csituation . Donorassistanc et oth eDepartmen to fVeterinar yan dTsets e ControlService si nth eWester nProvinc estarte d in1983 ,an d primarily focusedo ntechnicall yupgradin gth eleve lo fth e veterinary services (DeRooi jan dWood , 1990). Inthi sfirs t phaseth einventor yo fdiseas eoccurrenc ean dth edesig no f controlpolicie sreceive dmos to fth eattentio n (Chizyukae t al., 1987).

Trypanosomosisi spresen ti nth esout hwester npart so f theprovince ,an di npart so fKaom adistrict ,alon gth eborder s withth eKafu eNationa lPar k (Cortene tal. ,1988 ,DVTCS , 1990).Th etsets einfestatio nha sprogresse d froma virtua l absenceo ftsets eflie safte rth erinderpes tepidemic so fth e late19t hcentury .Th eflie sthe nbecam eextinct ,excep t ina fewsmal lpouche si nth eOkavang odelta ,sout ho fth eWester n Province,an di nth eKafu epar ki nth eEast .Sinc ethe nth e infestationha sadvance d steadilyunti lth epositio na s expressed inth ema po ffigur e5 wa sreache d (Clarence-Smith, 1977, VanKlin ke tal. , 1990b). Brucellosisi sendemic ,a swel l asBlac kQuarte ri na numbe ro ffoci ,an dHaemorrhagi c Septicaemiai sbecomin gincreasingl y important (Chizyukae t al.,1987 ,Corte ne tal. ,1988 ,DVTCS ,1990 ,D eRooi jan dWood , 1990).

Inth edesig no fcontro lmeasure sth esearc hfo rmor ecos t effectivemethod swa simportant .Th eCBP Pcontro lregulation s inforc ewer erevive dan dimproved .Emphasi swa spu to nth e improvemento fsuppor tfro man dunderstandin gb yth efarmer si n

23 Table2 . Resultso fsom estudie sint oproductivit yo fherd so f Barotsecattl ei ntraditiona lmanagemen t circumstances. reference average herd bull: calving calving mortality offtake herd structure cow X season size ratio calves adults

Lutke-Entrup 39 58.9 30X 3X (1971) (within afe w days)

Reveil (1975) 55 1 :1 5 67.9 May- 19.4 October

Besselan dDaply n 40 43X cow s 1 :2 0 41.4 June- 35X (u p (1977) 13% oxe n August to1 over3 yearo f years age) 14% calves

Abraham (1979) 68 14.8 June- 23.5X 7X November (26.4i n male calves, 20.7i n female calves)

Perrye tal . 34 40X cow s 1 :1 4 44 May- 20X 5X 4X (1984) November

theare aaffecte db yth emos tstringen tquarantin ean dcontro l measures,o nth ebasi so fa socio-economi c studyb yWoo d (1983).A programm eo fregula rinoculatio ncampaign sagains t trypanosomiasis,usin gIsomethamidiu mchloride ,i scarrie dou t since198 5 (vanKlin ke tal. ,1990b) . Regularvaccination s againstFoo tan dMout hDiseas ear ecarrie dou talon gth e southernborder ,whil evaccination sagains tHaemorrhagi c Septicaemiaan dBlac kQuarte rar ecarrie dou ti nwel l identifiedarea so fprevalenc e (DeRooi jan dWood , 1990).

Theoperationa lcos to fth eDepartmen t inth eprovinc e becameheavil ydependen to ndono rsupport .Onl ysom e2 0% o f thetota loperationa lcos twa sborn eb yth eDepartment ,o f which8 5% wer epersonne lcost s (DeRooi jan dWood , 1990).I t soonbecam eclear ,tha ti fsustainabl eveterinar y serviceswer e tocontinue ,thi scoul dno tb eattaine dwithi nth eexistin g structureo ffre eveterinar yservices .Therefore ,th eLivestoc k

24 Figure5 . Thedistributio nan dapproximat elocatio no fcattl e postsan dcrushpen si nth eWester nProvince ,Zambia .

*-»-—-.

'< _--

Crushpcnz/cattl« ports Herdi beloBfinf to

• predominantly (ruine Banageacnt tjntra 1 • predominantly gruinf management ifstaa 2

• Predominantly grating management irate» 3 • Predominantly gracing management eyetcm 4

25 DevelopmentProjec tWester nProvince ,a sth eprojec twa sterme d from1988 ,directe da nincreasin gpar to fth eattentio nt oth e restructuringo fth eveterinar y services,i nwhic hcos t recoverywa st obecom ea majo rissue ,a swel la smaintainin g thestandar do fth eveterinar yservices .

Inth eprojec tevaluatio nrepor to f198 7 (Chizyukae tal. , 1987)th eobjective so fth eLivestoc kDevelopmen tProjec tar e described.The yinclude :

- toprovid ea sustainabl einfrastructur efo rdiseas e control (includingcos trecover ymeasure s (DeRooi jan d Wood, 1990), toassis ti nth eformulatio no fa cattl edevelopmen t policy, todevelo pa nintegrate danima lhusbandr yan danima l healthextensio npackag efo rth etraditiona lfarmer .

Inorde rt oprovid eth enecessar ybackgroun dan dinformatio nt o achievethes eobjectives ,th eLivestoc kDevelopmen tProjec t engaged ina programm eo fresearc hinvolvin gsevera l disciplines.Apar tfro manima lhusbandr yan dhealth ,i t includedgrasslan dexpertise ,sociolog yan deconomy .

Theattentio no fresearc hi nth efirs tphas eo fth e projectwa smainl ydirecte dt oth ediseas esituation ,an dwa s thereforepredominantl yveterinar ytechnica lb ynature .I nth e secondphas emean swer et ob efoun dt oincreas eth e sustainabilityo fth eservice srendered .Th efocu so fth e researchcarrie dou ti nconnectio nwit hthi sai mwa sdirecte d muchmor etoward sidentifyin gway si nwhic hcos trecovery ,an d participationo fth elivestoc kowner si nfinancin gth e activitieso fth eDepartmen tcoul db epu tint opractic e (De Rooijan dWood ,1990) .Woo d (1986)detaile dth esocio-economi c researchrequirement sdeeme dappropriat efo rth egoal so fth e LivestockDevelopmen tProject .Thi sresearch ,par to fwhich , incidentally,alread ystarte dwel lbefor eth eofficia lstar to f theLivestoc kDevelopmen tProjec ti n1988 ,include dstudie s intoth eassessmen to fbenefit sderive d fromcattl e(Baars , 1987),th epositio no flivestoc kan dlivestoc kowner si n society (Beerling,1991 )an dth eownershi pstructure san dth e waysb ywhic hpeopl eacquir eo rdispos eo fanimal s (Beerling, 1986).

TheLivestoc kDevelopmen tProjec ta tpresen temploy sa n operational socio-economic analysisteam ,whic hcarrie sou tth e research inthi sfiel do nth ebasi so fth eproposa l (Wood,

26 1986).Analyse so fpar to fth eresearch ,an dth eimplication s ofth eresult sfo rth eplannin go fsustainabl eservic e provisionwer ediscusse db yWoo d (1988).

Optimisationo fth eproductivit yo fth elivestoc ki s considered animportan t fieldo fattentio no fth eproject .O f course,i ffarmer sar et opa yfo rth eservice srendered ,i ti s importanttha tthe yd oposse sth emean st od oso .A swa s mentionedbefore ,D eLeeu w (1990)indicated ,tha trisk - aversion,rathe rtha ncommercia lus eca nb econsidere dth emai n aimo fth etraditiona l farmer.Increase dcommercia luse , however,i slikel yt ob eth eresul to freductio no fth erisk s facedb yth efarme r (Matthewman,1980) .Th enutritiona lstatu s ofth eanimal si so fgrea timportanc ei nrelatio nt o productivityan dsinc eth eanimal ssolel ydepen do nth enatura l rangefo rthei rfoo dprovision .Therefor eLivestoc kDevelopmen t Projectstarte da nextensiv esurve yint oth eecolog yo fth e rangean dint oth ecarryin gcapacity ,i.e .th etheoretica l numbero fanimal stha tca nb esupporte db yth eavailabl efodde r inth eprovinc e (Jeanesan dBaars ,1990) .

Informationabou ttechnica laspect so fproductivit yprove d tob elargel ylacking ,o rwa srelativel youtdated .Thi s informationwa sthough tt ob eimportant ,i norde rt oidentif y areaso fconstraint si nth elivestoc kmanagement ,whic hmigh t aidi nth eassessmen to fth enee dfo rparticula rveterinar y measures,an di norde rt ob eabl et ogiv eindication sabou tth e developmentan dstructur eo fth eprovincia lher dthroug hth e useo fa provincia lher dmode l (DeRooi jan dWood ,1990) .Th e projecttherefor einitiate drelativel yobjectiv estudie sint o theproductivit yo fth etraditionall ymanage dcattle ,makin g useo fherd sfro mth ewhol eo fth eprovince .Thi sher d monitoringprogramm estarte dearl y1986 .

1.5.3. Herdmonitorin gb yth eLivestoc kDevelopmen tProject .

Inorde rt oapproac ha smuc ha spossibl ea nobjectiv e assessmento fth eproductivit yo fth ecattl ei nth eWester n Provincea programm ewa sstarte do fphysicall ymonitorin ga numbero fprivatel yowne dherds .Th emonitorin gwa st ob e carriedou tove ra prolonge dperio do ftime ,i nfou ro fth esi x districtso fth eprovince .I nprincipl e1 2monitorin gherd si n eacho fth efou rdistrict swer et ob eestablishe d (DeRooi jan d Wood, 1990).Sinc eon eher di nSenang aDistric tspli tu p shortlyafte rth estar to fth eprogramme ,th eactua lmaximu m numbero fherd stha twa sinvolve dwa s52 .

27 Practicaldifficultie snecessitated ,tha tth eselectio no f theherd swa sno tentirel ydon ea trandom .Sinc eth emonitorin g exerciseinvolve dtw oweekl yattentio nb yth eveterinar y assistantso fth ecamp swher eherd swer ebased ,i twa sdecide d toselec therd sfro mth erelativ evicinit yo fth eveterinar y assistantsresidence .I npractic eth eherd swer echose no nth e basiso frecommendatio nb yth eveterinar yassistants .I n generalthi sals omeant ,tha tth ekraa lowner sinvolve dgav e maximumcooperatio nt oth escheme .Th ekraa lowner shav eals o beengreatl y involved ina numbe ro fth esocio-economi c surveys thatwer ecarrie dou t (Beerling,1986 ,Baars ,1987) .

Inpractice ,th eveterinar yassistant swer eexpecte dt o paytwo-weekl yvisit st oth eherds ,an dt orecor dan ychange s thatha doccurre d inth eherd ssinc eth epreviou svisit .Thi s includedth ecalve sbein gborn ,th edat ethe ywer ebor nan d theirsex ,th edat eanimal sdied ,wer esol do rslaughtered ,o r weremove dou to fth eher dfo rothe rreasons ,an dth edat eo n whichcow swer emilke d forth efirs ttime ,o rwer edrie dof ,a s wella sth ereaso nfo rwhic hthe ywer edrie dof ,eithe rbecaus e ofweanin go ro fdeat ho fth ecalf .Assessin g intosom edetai l thereaso nwh yanimal swer eslaughtere do rmove dou to fth e herd,o rt owho manimal swer esold ,an dwhethe ro rno tth emea t ofanimal stha tdie dwa sused ,provide d insightint o practicalitiesan dsocio-economi caspect so flivestoc kkeeping .

1.6. Theai mo fth ethesis .

Theoveral lai mo fth ethesi sis ,t oevaluat eth eus eo f longitudinalphysica lmonitorin go fherd so fcattl eunde r traditionalmanagemen t forth edescriptio no fproductiv e performancean didentificatio no ffactor stha tinfluenc e productivity.Thi sevaluatio nshoul dprovid einsigh ti nth e suitabilityo fher dmonitorin g forth eprovisio no fbasi c informationfo rextensio nan dsolution sfo rconstraint st o productivity.

Inorde rt ocarr you tthi sevaluation ,th efollowin g hypotheseswer eformulated :

1. Mortality incattl ei ntradionall ymanage dherd si s importantly influencedb yenvironmenta lfactors .

2. Reproductiveperformanc ean dgirt hi ncattl ei n tradionallymanage dherd si simportantl y influencedb y environmentalfactors .

28 Environmental factorsma yinclud eclimat ean dseason ,grazin g circumstancesan dth emanagemen to fth eherds .

3. Intraditiona lherd so fcattl ei nth eWester nProvinc eo f Zambia,multipl eownershi pi sth ecustom ,an dtransfer s betweenherd simportantl yinfluenc eth eher dcompositio n (Beerling,1986) .

Theinformatio ncollecte dove rth eperio dApri l198 6til l April198 8wa suse dt otes tthes ehypotheses .I norde rt o describeth egrazin gcircumstances ,th eproductivit y calculationshav ebee nlinke dwit hgrazin gmanagemen t characteristicso fth evariou sarea san dmanagemen tpractice s inwhic hherd sinvolve d inth eHer dMonitorin gProgramm ewer e based,a sdescribe db yJeane san dBaar s (1990). Beerling (1986) describedqualitativ easpect so fownership ,o fmean so f acquiringan ddisposin go fanimals ,an do ftransfer sbetwee n ownersan dherds .Th eresult so fth eher dmonitorin gprogramm e wereuse dt oprovid equantitativ einformatio no nthes e subjects.

Theobservation so nth esubject srelate dt othes e hypothesesar ereporte d inChapte r2 .

4. Climatic factorsar edeterminan t inth eexposur eo fcattl e tohelmint hinfections .

5. Productivity (mortality,reproductio nan dgirth )o f traditionallymanage dcattl eca nb einfluence d favourably byregula rtreatmen tagains tintestina lparasite san d liverflukes.

6. Helminthparasite sar emor eimportan tdeterminant so f productiveperformanc etha nenvironment ,climat ean d management.

Theinterventio ntrial scarrie dou tt otes tthes e hypotheseswer estarte dafte rth ecompletio no fth efirs tpar t ofth estudy .Th einformatio ncollecte dbetwee nFebruar y198 9 andAugus t199 1ha sbee nuse dt otes tthes ehypotheses .Sinc e thesupervisio no fth eschem enecessaril y increased,th enumbe r ofherd sbein gmonitore dha dt ob ereduced .Ou to fth eorigina l 52herds ,2 0wer einvolve d inthi spar to fth eprogramme .

InChapte r3 ,attentio ni sgive nt oliteratur eo nth e influenceo fclimat eo nexposur eo fcattl ean do ninfluence so f helminth infectionso nproductivit y asfoun d insevera lregion s

29 of sub-Saharan Africa. The results of the intervention study are presented inChapte r 4.

Factors affecting productivity and their relevance for livestock development are discussed inChapte r 5. In this chapter, environmental, climatic and managerial factors, as well as socio-economic influences and influences of diseases are discussed. Remarks are included on the relevance for extension and further research.

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38 CHAPTER2 .

Productivitystud y

39 2.1. Herdmonitorin g intraditiona lcattl ehusbandr yo fWester n Province,Zambia ,I :Organisationa ldesign ,dat amanagement , descriptiveaspects ,an dth eher dstructur eo ftria lherd si n fourGrazin gManagemen tSystems .

E.G.M.va nKlink 1,J.J.F.M .Corten 1,an dD.M .Kalokoni 1.

Introduction.

Inman ycountrie si nsubsahara nAfrica ,th eprovisio no f veterinary serviceha sbee nfre eo fcharg efo rlivestoc kowner s (ILCA,1988) .Meetin gth ecos tinvolve d inth eprovisio no f livestockservice sha sbecom eincreasingl ydifficul t formos t ofth egovernment s (Masiga,1990 ,D eHaa nan dNissen ,1985) . Achievementsaccomplishe d inth e (recent)past ,suc ha swer e attained inth eJP1 5rinderpes tcampaign ,ar ei ndange ro f beinglos ta sa resul to fthi s (DeHaa nan dNissen ,1985) .I n manyAfrica ncountrie sther ei sa nee d forrigorou s restructuringo fth eveterinar y servicethroug h involvemento f theprivat esecto ra swel la sth edesig no fcos trecover y measures (Taylor,1990) .

InZambia ,th eDepartmen to fVeterinar y andTsets e ControlService si sa tpresen ti nth eproces so f investigating thepossibilitie s forrestructuring ,an ddesignin gth epolicie s bywhic hthi scoul db ebrough tabout .I nth eWester nProvinc e ofZambia ,th eLivestoc kDevelopmen tProjec t isinstrumenta li n facilitatingthi sproces s (DeRooi jan dWood , 1990). Inthi s frameworka serie so fresearc hactivitie sha sbee ninitiate di n ordert oestablis hth epositio nan deconomi c importanceo f cattlei nth erura lsociet y (Wood,1986 ,Baars ,1987) .Sinc e theproductivit yo f livestocki ntropica lcountrie si s importantly influencedb yth equalit yan dquantit yo fth e availablefodde r ('t Mannetje,1981) ,a nextensiv estud yo fth e grazingresource sha sbee nconducte d (Jeanesan dBaars ,1990) .

Objectivelyobtained ,quantitativ e informationo nth e productivityo fcattl ei nth eprovinc ewa sals ono tavailable . Thereforea stud yint oth eproductivit yo floca lcattle ,aime d atprovidin gthi sinformation ,wa spar to fth eresearc h programme.Apar tfro mdescribin gth eproductiv eperformance , thestud yaime da tevaluatin gth einfluenc eo fenvironmenta l

department of Veterinary and Tsetse Control Services, Livestock Development Project Western Province,P.O.Bo x910034 ,Mongu ,Zambi a

41 factors,suc ha sclimate ,grazin gresource san dher d management,o nproductivity .I twa sexpecte dtha tth e informationwoul dals oenabl eth eidentificatio no fconstraint s forproductivity .

Thispape rgive sa descriptio no fth eprojec tare aan d outlinesth eorganisationa ldesig nan dth edat amanagemen t applicationtha twa sdevelope d forus ei nth eproductivit y study.A compariso ni smad eo fth eher dstructur ei nth etria l herdsan dth emea nher dstructur ei nth eprovince .

I.Th eprojec tarea .

TheWester nProvinc eo fZambi ai slocate dbetwee nth e9 0 and18 0growin gday sisolines ,termin gi ta semi-ari dregio n (Jahnke,1982) .Th emai nsoi ltyp eo fth eWester nProvinc e consistso fKalahar isands ,covere dwit hsavanna hwoodland , interspersedwit hgrass ydepressions ,whic har ecalle ddambo s (Verbooman dBrunt ,1970) .A nimportan tfeatur ei sth eZambez i river,whic hrun sfro mnort ht osout hthroug hth eprovince ,an d whichform sth esouth-easter nborde ro fth earea .Figur e1 showsa sketc hma po fth eprovince .I nthi sfigur eth eoutline s offou rGrazin gManagemen tSystem sar eindicated ,o fwhic h table1 give sth emai ncharacteristic s (Jeanesan dBaars , 1990). Insystem s1 an d2 th eanimal sar emainl ykep tunde ra managementsyste m inwhic htranshumanc etake splace .Th e animalsar etrekke dtwic ea yea rove rdistance so fte nt ofort y kilometrest oan dfro mth efloodplain so fth eriver .I nfigur e 2th erelatio nbetwee nth eannua lrainfal lpattern ,th e waterleveli nth eZambez irive ran dth emovemen to fth eanimal s inth erespectiv esystem sar eindicated .I nsyste m 1th e animalsmov eou to fth eplai nonl ywhe nth eflood sforc ethe m tod oso ,whil ei nsyste m2 th eanimal sar emove dou twhe n watershortage so nhighe rlan dar eove ran dregrowt ho fgras s startsafte rth eonse to frains .I nsystem s3 an d4 th eanimal s arekep tunde rsedentar ymanagement .Thes esystem smainl y differi nterm so ffodde ran dwate ravailability .

II.Organisationa l structurean ddat acollection .

Theproductivit y study,th eHer dMonitorin gProgramme , wasaime da tprovidin gbasi cproductivit yparameters ,a t enablingidentificatio no fconstraint sface db ylivestoc k owners,an di twa st ob euse dfo rth econstructio no f provincialher dmodel st oallo wprojection so ffutur e developmentsi nth elivestoc kpopulation .Earlie rresearc hint o productivity involvingcattl ei nth eWester nProvinc ewer e

42 Table1 . Majorcharacteristic so fth eGrazin gManagemen t Systemso fWester nProvince ,Zambia ,a sidentifie d byJeane san dBaar s (1990).

System System Transhumant/ Grazing area Landunit/ Main water number name sedentary vegetation resources characteristics 1 Bulozi transhumant Floodplain: Floodplain, plain Plain season: plain •June- edges: grass Zambezi river, system February oxbows, lagoons Upland: Upland: savannah Flood season: + March - May woodland upland rivers, pools 2 Sesheke transhumant Floodplain: Floodplain: grass Plain season: system + June- Zambezi rivers, November oxbows, lagoons Upland: Upland: savannah Flood season: + December- woodland pools May 3 Eastern sedentary Dambos/river Dambos, river Whole year: valley valleys: valleys, plain upland rivers, system +Ma y- edges: grass sometimes October pools, handdu g wells Upland/plain Upland: savannah edges: woodland + November- April 4 Western sedentary Dry plains: Dry plains: North: whole plain + June- Marc h grass, bush year: upland system groups rivers Plain edges: Plain edges: South: wet + March -Jun e grass, woodland season: pools, waterponds dry season: waterponds, some riverso n the edgeo fth e area, handdu g wells

oftendesigne da squestionnair e surveys,an dcovere donl y limitedarea so rlimite dperiod s (Lutke-Entrup,1971 ,Besse l andDaplyn ,1977) . Inth epresen tstud y5 2herds ,distribute d overth eprovince ,wer epurposivel y selectedan dphysicall y monitoredove ra prolonge dperio do ftime ,i norde rt oobtai n relativelyobjectiv einformation .

43 Figure1 . Mapo fth eWester nProvinc eo fZambia ,showin gth e districtboundarie san dth eapproximat elimit so f theGrazin gManagemen tSystem s (Jeanesan dBaars , 1990).

•^*» «""^ mmm Intern . boundary

»«»w«»**w Provincial boundary

Approx. fcounaariaa of Grazing tninafawmt System?

M«tr i ci bounaarlM

Tryfr"^ rlvar

44 Figure2 . Rainfallfigure san dth ewaterleve lo fth eZambez i riveri n198 9i nth eWester nProvinc eo fZambia .I n thebar sabov eth egrap hth elocatio nthroug hth e yearo fth eherd si nth etw otranshuman tsystem si s indicated.Th ewaterleve li sgive ni ninches .

Location of hards • in plain outatd» plain Y/X appro*, movamant period sy«fmi I W/M\ 1 System 2 "EM

Rainfall Water level

300 200

100 I

123456789 101112 Month 1

Allherd swer evisite dever ytw oweek sb y(Senior ) VeterinaryAssistant s ((S)VA),an dever ythre emonth sb yth e DistrictVeterinar yOfficer s (DVO)o fth edistrict si nwhic h theherd swer ebased .Eac hanima lwa sindividuall y identified bya nearta gwit ha number ,whil eeac hher dwa sidentifie db ya lettercode .Th e(S)VA swer eexpecte dt orecor dal levent s happeningi nth eherds ,relate dt obirths ,deaths ,slaughters , sales,transfer san dne wentries .Durin gth ethree-monthl y visitsb yth eDVO sthi sinformatio nwa schecke dan dentere do n field lists.A tth esam etim egirt hmeasurement swer etake nt o beuse dfo rth eevaluatio no fgrowth .I ntabl e2 th edetail s areliste do fth erecord stha tha dt ob ecollected .

45 Table2 . Contentso fth erecord stha twer ecollecte ddurin g theregula rvisit sb yth e (Senior)Veterinar y Assistants (SVA)an dth eDistric tVeterinar y Officers (DVO)i nth eHer dMonitorin gProgramm eo f theLivestoc kDevelopmen tProjec tWester nProvince .

First visitan dne wentrie s Consecutive visits ((S)VA: every2 weeks , DVO: every3 months ) Cows -Ear-taggin g -dat eo fcalvin g -(estimated )ag eo rbirt h date -Se xo fth ecal f -Wit h calfo rno t -Colou ro fth ecal f (for -Dat eo fbirt ho fcal f identification purposes) -Bein g milkedo rno t -dat eo fstar t milking -Dat emilkin g started -dat e milking stopped -I fno twit h calf:cal f deado r -dat esucklin gstoppe dan dreas o weaned ofstopping ;deat ho rweanin go ft h -Dat eo fdeat ho rweanin go f calf the calf -dat eo fabortio n -Aborte do rno t -dat ean dreaso no fremova l(deat h -Dat eo fabortio n sale, slaughtero rtransfer ) Males, Oxenan d -Eartaggin g -Girt hmeasurement san dconditi o youngstock belowth e -Girt h measurementsan d scoringo fyoungstoc k ageo f2 year s condition scoringo fyoungstoc k -dat ean dreaso no fremova l(deat h sale, slaughtero rtransfer )

Usingth ePanacea (c)2genera lpurpos edat amanagemen t programme,application swer edesigne d forth emanagemen tan d processingo fth edat a (PanLivestoc kServices ,1987a , 1987b).

III. Datamanagement .

Figure3 show sa flo wchar to fth eprocedure san d datasetsinvolve d inth edat amanagemen tapplicatio n(Hanks , 1986, 1987).Eac hher di srepresente db yon edataset .I nth e herddatasets ,al lanimal sar ei nprincipl erepresente db yon e record.

Animportan tai mo fusin gthi sapplication ,i sth e protectiono fth einformatio ntha tha salread ybee ncollected . Beforeenterin gne wdata ,par to fth einformatio ni nth eher d dataseti scopie dt oa separat edatase tcalle dENTRY .Onl y animalsstil lpresen ti nth eher dwil lappea ri nENTRY ,whil e informationo nremove danimal sremain suntouched .Throug ha

46 Figure3 . Flowchart showingth eprocedure sinvolve d inth e datarecordin gapplicatio nuse di nth eHer d MonitoringProgramm eo fth eLivestoc kDevelopmen t ProjectWester nProvince .

Herd Datasets ""I i 1i 1 i 1 r •1 i- I

i i i i i i -„• I I I I I I . 1 Option 1: transfer Option 9: prepare jABORTj dHtato ENTRY lists TUT Option 2: eider I ENTRY Field lisle COW data

Option 3: enter u 8 aTRACT! MALE and OXEN data I Option 6: transfer data I Option A4 : unter -4>aa.MMJ to datasets •A YOUNGSTOCKTOCK dat( a / I I Option 9 and 6: enter Option 7":chec k NEW ENTRIES newlyentere d data

serieso foptions ,informatio nca nb eentere d foreac ho ffiv e categorieso fanimals ;1 .cow sove rth eag eo ftw oyears ,2 . malesan doxe nove rth eag eo ftw oyears ,3 .youngstoc k (all animalsbelo wth eag eo ftw oyears) ,4 .ne wcow san d5 .ne w males,oxe nan dyoungstock .Usin goptio n7 ,th eENTR Ydatase t canb echecke d forerror so rincomplet e information.Th e checklisti tproduce senable sfiel dstaf ft ocorrec terror sa t thetim eo fth enex tvisit .Optio n8 ca nb euse dt otransfe r thedat at oth eher ddatasets .Informatio no nalread yexistin g animalswil lb eupdate d inth erespectiv erecord ,i f alterationshav etake nplace .Ne wrecord swil lb eproduce dfo r cowswit hne wlactations ,newbor ncalve san dne wentrie sint o theherd .Abortion san ddraugh tpowe rdat aar eappende dt oth e appropriatedatasets .

Anotheroptio nproduce sprintout so fth eher ddatasets ,

47 onwhic hal lanimal stha twer epresen ta tth etim eo fth elas t recordedvisi twil lappear .O nth efiel d liststh eanimal sar e categorised inthre eo fth efiv ecategorie smentione dearlier : cows;male san doxen ;o ryoungstock .Th ene wentrie s (categories4 an d5 )wil lappea ri nthei rappropriat elist .Th e field listsserv ea schec klist sfo rth eDVO scarryin gou tth e threemonthl yvisits ,an da tth esam etim eallo wth eentr yo f thene winformation .Afte rth evisi tth efiel d listsar esen t backt oupdat eth ecomputerise dinformation .

IV. Datasummar y andanalysis .

Forth eevaluatio no fth einfluence so fenvironmenta l factorso nproductivit yth einformatio nwa suse dt odescrib e variablestha twer ea smuc ha spossibl eobjectivel ymeasurable . Thevariable sevaluate dar eth egirth ,th epercentag eo fth e animalstha tdi eo rar eslaughtere d ina on eyea rperiod ,an d lactationrelate d intervalsa sa measur eo freproductiv e performance,includin gth ecalvin ginterval ,th einterva l betweenth ebirt ho fa cal fan dth emomen tth efarme rstart s milking,th eperio dth eco wi smilked ,th eag ea twhic hth e calfi sweane dan dth einterva lbetwee nweanin gan dth ebirt h ofth enex tcalf .Th epercentag eo fanimal ssol dfro mth eher d ina on eyea rperio dwa sals oevaluated .

Thegirt hwa suse da sa measur eo fgrowth .Logisticall y itwa sno tpossibl et ophysicall yweig hanimals .Althoug h Corten (1988)describe sa formul afo rth ecalculatio no fweigh t fromth egirt hmeasurement ,th egirt hwa suse d inth e statisticalevaluatio nalso ,sinc ei tcoul db eeasil ymeasured . Applyingth eformul ao fCorte nwoul d introducea nextr aerro r inth eanalysis .

Thepercentag eo fanimal stha tdi eo rar eslaughtere di s animportan t factori ndescribin gproductivity .I tdetermine s themargi nfo rgrowt ho fth eher dan dth eexten to fth e possibilitiest osel lanimals .Logisti cRegressio nanalysi s (Hosmeran dLemeshow ,1989 )wa suse dt oevaluat eth eOdd sRati o (OR)fo ranimal st odi eo rb eslaughtered .

Thecalvin ginterva lwa suse drathe rtha ncalvin g percentageo rweanin gpercentage .Th egrea tvariet y inth eher d compositionsan dth eag ea tfirs tcalvin gmad ei tdifficul tt o definea prope rdenominato r forth ecalvin gpercentage .Th eag e atweanin gwa sals ogreatl yvariable ,a susuall yth efarmer s didno tactivel ybrin gabou tweaning ,makin g itdifficul tt o useth eweanin gpercentag ea swell .Calve swer eofte nweane db y

48 thecow sb yth etim eth enex tcal fwa sabou tt ob eborn . Thereforeth echoic ewa smad et ous eth ecalvin g intervalan d toevaluat edeath so fcalve sindependently .

Theothe rinterval smentione dwer euse dsinc ea rathe r largeinfluenc eo fth econditio no fth eanimal so nth elength s ofth eperiod smentioned ,eithe rwit h (intervalcalving-star t milking,lengt ho fth emilkin gperiod )o rwithou t (ageo fth e calfa tweaning ,interva lbetwee nweanin gan dth enex t delivery)th edirec tinfluenc eo fth eher dmanager ,wa s expected.Th ecalvin ginterval san dth eothe rlactatio n characteristicswer eevaluate dusin ganalysi so fvariance .

Saleo fanimal si sa nimportan twa yo fputtin ganimal st o productiveus e (Beerling,1991) .Sale sfigure sgiv ea n indicationo fth epotentia lo fherd so rgroup so fherd st o generate financialbenefits .Theoreticall y itcoul db eargue d thatherd sperformin ga ta hig hproductivit y levelwoul dhav e moreanimal savailabl efo rsale ;a sMatthewma n (1980)states , ifrisk sar ereduced ,farmer sar elikel yt orespon dt o commercialisationefforts .However ,sellin ganimal sremain sth e decisiono fth eowne ro rcaretaker ,an dthi sdecisio ni smad e forindividua lanimal sfo rwel ldefine d individualreason s (Beerling,1986 ,1991) . Inth eHer dMonitorin gProgramm eth e salesfigure sar edefine da sth epercentag eo fth etota lnumbe r ofanimal stha tar esol di na on eyea rperiod .

Thedat amanagemen tprogramm ewa sals ouse dt odesig n applicationsfo rth eproductio no fdat asummarie si n preparationo fth eanalyses .On eo fth eapplication ssummarise s theinformatio nuse d forth eevaluatio no freproductiv e performance.

Anotherapplicatio nproduce dher dproductivit yprofile s ofgroup so fherds ,givin g impressionso fth emortality ,sale s andslaughte rpercentage sfo rvariou sag ecategorie sove ron e yearperiods ,o nth ebasi so fanima lyears .Thi smake s allowancefo rth edynami cnatur eo fth eher dstructure .Ther e appearedt ob ea considerabl emovemen to fanimal sbetwee n herds.Th eher dstructure si ngroup so fherd si nth efou r GrazingManagemen tSystem smentione d intabl e1 ,arrive da ti n thismanner ,wer ecompare dwit hth eresult so fth eannua l livestockcensu scarrie dou tb yth eDepartmen to fVeterinar y andTsets eContro lService si n198 8 (VanKlin ke tal. , 1990). Theher dstructure sfro mbot hsource sar egive ni ntabl e3 .

49 Table 3. Herd structure as found forher d groups consisting of theherd s from four Grazing Management Systems of Western Province, Zambia, calculated overth e period 1/4/87 till 31/3/88 (period II),an da s found inth eannua l livestock census of1988 , carried outb yth eDepartmen t of Veterinary and Tsetse Control Services.

CMS source Females Males Oxen Total Mean size

study 585 66.3 126 14.3 172 19.5 883 80.3

census 125147 67.7 29022 15.8 30215 16.3 184384 76.0

study 354 64.4 83 15.1 113 20.5 550 110.0

census 24750 66.2 6157 16.5 6395 17.2 37302 99.0

study 472 61.2 117 15.2 182 23.6 771 59.3

census 68640 62.8 18964 17.7 18142 19.5 105746 49.1

study 213 66.4 60 18.7 48 14.9 321 64.2

census 106734 64.2 28883 17.9 27854 17.1 163471 52.0

IV. General remarks and discussion.

Though inbot h Grazing Management System 1an d2 transhumance ispracticed , there isa striking difference between thepractic e inbot h systems (table 1, figure 2).I n Grazing Management System 1th eherd s seem to have their base in the floodplain. Only when they are forced tod os ob yth e rising floods,th ecaretaker s take their animals outo fth e floodplain onto higher grounds.A s soon asth erecedin g floods allow them to return, they doso .I nGrazin g Management System 2 therevers e seems tob eth ecase . Here, theanimal s dono t move into the floodplain untill water and food shortages force them tomov e closer toth erive r banks inth ecours e ofth edr y season. As soon asth erain s start, thegras s starts regrowing and thewate r situation improves, thecaretaker s move their animals outo fth e floodplain. A reason forth e difference between thetw osystem s isno teas y to discern. The cattle population pressure ishighe r inan daroun d the Bulozi floodplain than inth eSeshek e area. Therefore less spacema y be left inth ehighe r grounds around theBuloz i floodplain for

50 allcattl etha thav et omov eou tdurin gth eflood s (VanHorn , 1977).Becaus eo fthei rlon gstay si nth eplain sth eamoun tan d qualityo fth efodde ran dth eavailabl eacreag ei sunde rsom e pressurewhe nth eflood sar erising .Th eanimal sthe nmov eou t toarea swher eth ecattl epopulatio ni salread yrelativel y high.Sinc eth efloodplain si nth eSeshek eare aar esmaller ,i t mightb etha tto olittl egrazin gresource si nth eplain sar e available.I twoul dhoweve rseem ,tha tth edecision st omov e animalsou to fth eplain sar emad eou to fshortag ei ngrazin g resourcesi nth eBuloz isystem ,wherea si nth eSeshek esyste m notth epressur eo nth egrazin gi nth eplains ,bu tth e availability ofeve nbette rgrazin gelsewher edetermine sth e decision.

Theherd swer eno tchose na trandom .Logisti c difficultiesrelate dt oattainabilit yb yth eveterinar ysta f anda "workable "her dsize ,a swel la sth ecapabilit yan d willingnesso fth eher dmanager st oparticipat ei nth e programmemad ei tinevitabl et omak ea weighte dchoic efo rth e herdst oenrol li nth estudy .

Faugérean dFaugér e (1986)describe d systemsfo rth e collectiono fdat awit hth eai mo fevaluatin g individual performanceo fsmal lruminants .Th edat acollectio nproces so f thesurve ypresente d inthi spape ri sals obase do nindividua l records.Thes ewer eno tprimaril yuse dfo rth eevaluatio no f individualperformance ,bu tfo rth eevaluatio nfo r environmental factorsinfluencin gproductivity .Th eautomate d systemsdesigne d fori tcoul di frequire db eadapte dt osui t them forth epurpos eo findividua lperformanc eevaluation .Thi s couldpla ya par twher eselectio nan dbreedin gprogramme sar e persued.Thi swa showeve rno tth escop eo fthi sprogramme ,no r ofth eLivestoc kDevelopmen tProject .

Theinformatio nnecessar y forth ecalculatio nan d evaluationo fth eparameter schose ni srelativel yeas yt o obtain.A sMatthewma nan dPerr y (1985)stated ,i ti sdifficul t toobtai nexac tinformatio no nth eher ddynamic si nth e traditional livestocksystem si nAfric aan di ti stherefor e essentialt ous eth eminimu mavailabl edat at odevelo pmethod s ofproductivit y assessment.The yuse dth eher dstructur ea sa basisfo rdescribin gperformance ,takin gth evie wtha t fertilityan dmortalit yar edirectl yreflecte d inth eher d structure.Thi smetho dwil lb eappropriat efo rth edescriptio n ofth eperformanc eo findividua lherds .I twoul db eles s suitablefo rth estatistica levaluatio no fenvironmenta l influenceso nperformance .Thoug hi ti sver yusefu lan dsimple ,

51 itdoe sno taccoun t fortransfer sbetwee nherd sa sanothe r factor inbringin gabou tth eher dstructur e (Beerling 1986).I n thepresen t studyth echoic ewa smad et obas eth einformatio n onrecord sdraw nfro mindividua lanimals .A tth esam etim emos t ofth eparameters ,specificall ythose ,relate dt oreproduction , couldb ecalculate ddirectl y fromth erecorde ddata .

Theapplicatio nuse d forth erecordin g andmanagemen to f fielddat aprove dt ob ea satisfactor y fieldtool .Th e background informationprovide db yth eupdate d fieldlist s frequentlydraw sth eattentio no fth efiel dworke rt o discrepancies,whic h inmos tcase sca nb ecorrected .Th e informationalread yrecorde d isno taltere dbefor ean yne w resultsar echecke dan dfoun dcorrect .

Thoughsom edifference sbetwee nth estructure so fth e herdgroup sfro mth efou rGrazin gManagemen t Systemsan dthos e found inth ecensu soccurred ,the ywer eno t foundt ob e significant (table 3). Informationo nth ecompositio no fherd s inth eprovinc ewa sals ogive nb yBessel lan dDaply n (1977)an d byPerr ye tal . (1984).Besse lan dDaply n (1977)foun d4 2% cows,1 3% oxe nove r3 years ,an d1 4% calve si n4 2herd si n Mongudistrict .Perr ye tal . (1984)foun da comparabl e percentageo fcows .Thi si sfairl ycomparabl ewit hth enumbe r offemale sove rth eag eo fthre eyear sa sfoun d inth eher d monitoringprogramme ,a swel la swit hth enumbe ro foxe nove r threeyears .Bot hpublication s indicaterathe r smallerherd s thanfoun d inth eher dmonitorin gexercise ,a swel la si nth e census.

Acknowledgements. Theauthor swis ht othan kth eDirecto ro fth eDepartmen to f Veterinary andTsets eContro lService s forhi spermissio nt o submitthi spape r forpublication .W eals owis ht othan kDr .J . Hanksan dDr .J . Izaksfo rthei rassistanc e inth edevelopmen t ofth eautomate dprocedures .

Literature.

1. Baars, R.T.M. (1987). Assessment of benefits derived from herds inWester n Province of Zambia. Report Livestock Development Project, Departmento f Veterinary and Tsetse Control Services,Wester n Province, Zambia. 2. Beerling, M.L.E.J., (1986).Acquisitio n and alienation of cattle inWester n Province.Dept . of Vet.an d Tsetse Contr.Serv . Lusaka, Zambia. 3. Beerling, M.L.E.J., (1991). The advantage of having cattle.Dept . of Vet. and Tsetse Contr.Serv. , Mongu, Zambia.Departmen t of Veterinary and Tsetse Control Services,Mongu , Zambia, RDP Livestock Services, Zeist, TheNetherlands .

52 4. Bessel, J.E.an d M.G.Daply n (1977).Dairyin g inZambia , thetraditiona l sector. University of Nottingham's farmmanagemen t investigations forZambia , Bull.no . 3. 5. Corten, J.J.F.M. (1988). Productivity of cattle inWester n Province, Zambia (third draft). Department ofVeterinar y and TsetseContro l Services,Anima l DiseaseContro l Project Western Province,Mongu , Zambia.

6. Faugére,0. ,an d B. Faugére (1986). Suivi de troupeaux et controlede s performances individuellesde spetit s ruminantse nmilie u traditionel africain. Aspectsméthodologiques .Rev .Elev .Med .vet .Pay s trop.,3 9 (1),29-40 .

7. Haan,C .de ,an d N.J.Nisse n (1985).Anima l health services inSubsahara n Africa:Alternativ e approaches.Worl d Bank Technical Paper no.44 ,Worl d Bank, Washington, USA. 8. Hanks,J . (1986). Herdmonitorin g and informationmanagemen t inth eDepartmen t ofVeterinar y and TsetseContro l Services,Wester n Province,Zambia . Consultants report.PA N Livestock Services,Readin g UK. 9. Hanks,J . (1987). Theher dmonitorin g packagedevelope d for theDepartmen t of Veterinary and TsetseContro l Services,Wester n Province,Zambia . Consultants report.PA N Livestock Services,Readin g UK.

10. Horn, L.va n (1977).Agricultura l history of Barotseland. In:R .Palme r &N . Parsons,eds. :Th e rootso f rural poverty inCentra l and SouthernAfrica . Heinemann, London. 11. Hosmer,D.W. , and S.Lemesho w (1989).Applie d logistic regression.Joh nWile y and Sons,Ne w York,USA . 12. International Livestock Centre forAfric a (1988).Annua l report 1987.ILCA , AddisAbaba , Ethiopia. 13. Jahnke, H.E. (1982). Livestock production systemsan d livestockdevelopmen t in tropical Africa.Kiele rWiss .Seh .Verla g Vauk.Kiel .

14. Jeanes,K.W. , andR.T.M .Baar s (1990).A rangeland resource appraisal ofWester n Province,Zambia .Repor t Department ofVeterinar y and TsetseContro l Services, Mongu, Zambia.

15. Klink,E.G.M ,van ,M.M .Kawambw a andD.M . Kalokoni (1990). Thecattl e population of theWester n Province,Zambi a on thebasi s of theAnnua l Livestock Census 1987, 1988,1989 .Departmen t ofVeterinar y and TsetseContro l Servicesan d RDP Livestock Servicesb.v. ,Wester nProvince ,Zambia . 16. Lutke-Entrup, J. (1971). Limitations andpossibilitie s of increasing market production of peasant African cattleholder s inWester nProvince , Zambia. University of Zambia, Inst,o fAfr .stud .comm . no.4.

17. Mannetje, L.t' ,(1981) . Problemso fanima l production from tropical pastures. In: J.B. Hacker, Ed.:Nutritiona l limitst oanima l production frompastures . Proceedings of an international symposium held at St.Lucia , Queensland, Australia,Aug . 24-28,p p67-85 . 18. Masiga,W.N . (1990).Achievement s anddifficultie s of animal health services and theapplicatio n ofpreventiv eanima l health measures inAfrica .Proc .6t h Int. Conf.AITVM , Wageningen, theNetherlands ,28t h Aug.-1st Sept. 1989,p p63-67 .

19. Matthewman, R.W. (1980).Anima l disease control,Zambia , cattleproductio n and health. FAO report AC:DP/ZAM/77/002. 20. Matthewman, R.W., andB.D .Perr y (1985).Measurin g thebenefit so fdiseas e

53 control:relationshi pbetwee nher d structure,productivit y andhealth .Trop . Anim.Hlt hProd . 17,39-51 .

21. PanLivestoc k Services (1987a).Th ePanace aUse rGuide .VEERU , Reading,Unite d Kingdom. 22. PanLivestoc k Services (1987b).Th ePanace aPrecompiler .VEERU , Reading,Unite d Kingdom. 23. Perry, B.D.,B .Mwanaumo , H.F.Schels ,E .Eiche r andM.R .Zama n (1984).A stud y ofhealt h andproductivit y of traditionallymanage d cattle inZambia .Prev .Vet . Med.2 ,633-653 .

24. Rooij,R.C .de ,an dA.P .Woo d (1990)."Wh oPay sth eBill" :Toward s Sustainable CattleDevelopmen t inWester n Zambia.Proc .6t h Int.Conf .AITVM ,Wägern'ngen , theNetherlands ,28t hAug.-1s t Sept.1989, .

25. Taylor,W.P .(1990) .Achievements ,difficultie s and futureprospect s forth e control ofRinderpes t inAfrica .Proc .6t h Int.Conf .AITVM , Wageningen, the Netherlands,28t hAug.-1s t Sept. 1989,p p84-90 . 26. Verboom,W.C. ,an dM.A .Brun t (1970).A necologica l surveyo fWester nProvince , Zambia;volum e 1,Th eenvironment ;volum e2 ,Th egrassland s and their development. Land resourcestud yno .8 ,Lan dResource sDivision ,Directorat eo f OverseasSurveys ,Tolworth ,Surrey ,UK .

27. Wood,A.P . (1986).Researc h proposal:Polic y implications ofsocio-economi c aspects ofcattl ekeepin g inWester n Province,Zambia . Thepolytechnic , Huddersfield, United Kingdom.

(submitted for publication.)

54 2.2. Herdmonitorin g intraditiona lcattl ehusbandr yo fWester n Province,Zambia ,II :surviva lrate so fcalves ,mortalit yan d slaughter figures,an dsale sfigures .

E.G.M.va nKlink 1,J.J.F.M .Corten 1,K .Frankena 2,E.M . Chiposa1.

Introduction.

InAfrica ,approximatel y 80% o fth elivestoc ki skep t undertraditiona lmanagemen t (Dicko,1990 ,Brumby ,1986 ,Brumb y andTrail ,1986) . Inman ycase slivestoc ki smaintaine di n environmentsles ssuitabl efo rcro pproduction ,an di s thereforeofte no fmajo reconomi cimportanc et othei rkeepers . Inth eWester nProvinc eo fZambi acattl ekeepin gha sbee na wellestablishe dpractic efo ra tleas tth elas t30 0year s (Roberts,1976) .A sa resul to fclimati c factors,an da relativelabou rdeficit ,th ecro pproductio n inth eprovinc ei s largelybelo wself-sufficienc yleve l (VanHorn ,1977) . Inth e mixedfarmin gsyste mo fth earea ,cattl ea sprovider so fmanur e anddraugh tpowe rar eindispensabl e (Peters,1960 ,Puzo ,1977) . Cattlear eequall yimportan ta sa mean so faccumulatin gwealt h andprovisio no fsecurity ,a swel la sprovisio no fcas hincom e ifs orequire d (Beerling, 1986).

Inth eframewor ko fth eLivestoc kDevelopmen tProjec ti n theWester nProvince ,operatin gwithi nth estructure so fth e Departmento fVeterinar yan dTsets eContro lServices ,a serie s ofstudie sha sbee ncarrie dout ,i norde rt oestablis hth e importancean dpositio no fth ecattl eindustr y (Wood,1986 ,D e Rooijan dWood ,1990) .Baar s (1987)reporte do neconomi c aspectso fth ecattl einductry ,whil eBeerlin g (1986,1991 ) discussed socio-economic features.Publication sdealin gwit h productivity ofcattl ear eofte noutdate dt osom eexten tan d touchonl yo nlimite daspect so fcattl ekeepin g (eg.o nmil k productiononly ,o ro nofftak eonly) ,o rwer ebase do n informationtha twa sgathere d ina limite dare a (Gluckman,

department of Veterinary and Tsetse Control Services, Livestock Development Project Western Province,P.O.Bo x910034 ,Mongu ,Zambi a

department of Animal Husbandry, Agricultural university Wageningen, P.O.Box 833, Wageningen, The Netherlands

55 1941, Lutke-Entrup,1971 ,Bessel lan dDaplyn ,1977 ,Rennie , 1982).Therefore ,a researc hprogramm ei nth efiel do f productivityo fth eloca lcattl ewa sinitiated .Apar tfro m providingbasi cproductivit ydata ,th estud ywa saime da t identificationo fconstraint so nproductivity .Mortalit y isa n importantparamete r forth eevaluatio no fproductiv e performancean do ffactor saffectin gperformance .Slaughte ran d salesfigure sma ygiv ea nimpressio no fth ecapabilit yo fherd s toproduc esurplu sanimal sfo rofftake .A ssuch ,the yals ogiv e informationo nfactor sinfluencin gperformance .

Inthi spaper ,th emortalit yan dslaughte rfigure san dth e salesfigure sa sfoun di nth eproductivit y studyar eevaluated . Theai mo fthi sevaluatio ni smainl yt oidentif yenvironmental , climatican dmanageria lfactor sinfluencin gth eperformanc ei n theserespects .Mortalit yamon gyoun gcalve si smuc hhighe r thanamon gadul tcattl e (Perrye tal. ,1984 ,Besse lan dDaplyn , 1977). Inorde rt oillustrat ethis ,surviva lrate so fcalve sa t intervalsdurin gthei rfirs tyea ro fag ewer ecalculated .

Materialsan dmethods .

TheHer dMonitorin gProgramme .

Theorganisationa ldesig nan ddat amanagemen to fth e programmewer epresente d ina nearlie rpape r (VanKlin ke tal. , 1994).Th eprogramm einvolve dregula rvisit so fprivatel yowne d herdsb y (Senior)Veterinar yAssistant s (fortnightly),an d DistrictVeterinar yOfficer s (three-monthly).Durin gth efort nightlyvisit sal levents ,suc ha sbirths ,deaths ,slaughters , salesan dothe rremoval stha thappene d inth eperio d sinceth e precedingvisi twer erecorded .Durin gth ethree-monthl yvisit s newanimal swer eeartagged ,an dth einformatio nwa schecke do n thebasi so ffieldlists .

Climate.

InZambi aa mild ,thoug hrelativel ydr ytropica lclimat e prevails.I nthi sstud ya devisio no fth eyea ri nfou rseason s isused ,eac hspannin ga thre emont hperiod ,fairl ycoincidin g withth eclimati cseasons :seaso n1 i sth elat erain yseaso n fromJanuar yt oMarch ;seaso n2 th edr yan dcoo lseaso nfro m Aprilt oJune ;seaso n3 i sth eho tdr yseaso nfro mJul yt o September;seaso n4 i sth eearl yrain yseaso nfro mOctobe rt o December.Sinc ea considerabl eannua lvariatio nspecificall yi n theamoun to frainfal li sseen ,th esurve yperio dwa sspli t intotw oon eyea rperiod sfo rth epurpos eo fanalysis .I n

56 period Ith eamoun to frainfal lwa slowe rtha ni nperio dII .

Projectarea .

Amor edetaile ddescriptio no fth eprojec tare awa sgive n byVa nKlin ke tal . (1994).Th eprovinc econsist so fsi x districts.I nfou rdistricts ,Mongu ,Kalabo ,Senang aan d Sesheke,herd swer esituate dtha twer einvolve d inth estudy . Nomonitorin gherd swer ebase di nLukul uan dKaoma .Herd swer e basedi neac ho fth efou rGrazin gManagemen tSystems ,a s describedb yJeane san dBaar s (1990).

Herds.

Ineac hdistric ttwelv eherd scooperated .I non eo fth e districtsa her dspli tu pshortl yafte rth estar to fth e programme,bringin gth etota lnumbe rinvolve dt o52 . Approximately 6000hea do fcattl ewer einvolve d inth eexercis e overth ewhol eperiod .Th eherd sconsiste do fBarots ecattle ,a longhorne dSang abree d (Masonan dMaule , 1960).Th eherd swer e monitoredove ra tw oyea rperiod ,fro mfirs tApri l198 6t o31s t March1988 ,thoug hno tal lwer einvolve dth ecomplet eperiod .

Monitoringprocedures .

Theherd swer evisite donc eever ytw oweek sb yth e (Senior)Veterinar yAssistant s ((S)VA)o fth earea swher eth e herdswer ebased .Durin gthes evisit sal lchange stha tha d occurred inth eherd swer erecorded .Onc eever ythre emonth s theDistric tVeterinar yOfficer so fth edistrict si nwhic hth e herdswer elocate dentere dth einformatio ngathere do nfiel d lists,produce db ya compute rapplication ,designe d forth e herdmonitorin g schedule,usin gth ePanacea (c)3genera lpurpos e datamanagemen tprogramm e (VanKlin ke tal. , 1994).Update d fieldlist swer eproduce dafte renterin gth einformatio n received fromth efiel dafte reac hvisit .

Parametersevaluated .

Mortalitywa sdefine da sth enumbe ro fanimal stha tdie d withina on eyea rperio da sa percentag eo fth etota lnumbe ro f animalstha tha dbee npresen ti nth eherd sdurin gtha ton eyea r period.Th eslaughte rfigure san dth esale sfigure swer e defined inth esam emanner .

3 (c)Pa nLivestoc kService sLtd. ,Readin gUK . 57 Thesurviva lrate so fcalve swer edefine da sth enumbe ro f malean dfemal ecalve stha twer estil laliv ea tth eag eo fon e month,thre emonths ,si xmonth san don eyear ,a sa percentag e ofth enumbe ro fcalve sbor ni na on eyea rperiod .Th e resultingpercentag eprovide sa descriptiv eimpressio no fth e courseo fcal fsurviva lthroug hth efirs tyear .

Calculations.

Themortalit yan dslaughter san dsale sfigure swer e determinedb ycalculatin gth enumbe ro fanimal stha tdied ,wer e soldo rwer eslaughtered ,a sproportion so fth etota lnumbe ro f animalstha twer epresen tdurin geac ho fth etw oon eyea r periods.Th eLogisti cRegressio nstatisti cwa suse dt oevaluat e theinfluenc eo fvariable so nth emortalit yan dslaughter san d salesfigure s (Hosmeran dLerneshow ,1989) .Wit hthi sstatistic , outcomevariable swit hdiscret evalues ,suc ha sth eproportion s mentioned,ca nb eevaluated .Th eprocedur ecalculate sth eOdd s Ratio (OR).Th eO Rindicate sth estrengt ho fassociatio n betweena facto rt ob eevaluate dan dth eeven tbein gdescribe d (Martine tal. , 1987).Th eO Ri sth erati obetwee nth e probabilitytha ta neven ti shappenin gunde ron eo fth evalue s ofa nindependen tvariable ,a scompare dt oth eprobabilit ytha t ithappen sunde ranothe rvalu eo fth esam evariable ,th e reference.I fth eO Ri sclos et o1 ,th echanc etha tth efacto r playsa par ta sa ninfluenc eo nth eeven tbein gdescribe di s little;th ebigge rth edifferenc ewit h1 ,b ei tnegativ eo r positive,th ebigge rth einfluenc eo fth efacto ri slikel yt o be. Inlogisti cregression ,th eO Ri sgive nb y t&. Ifa n independentvariabl eha smor etha ntw ovalues ,a swa sth ecas e forGrazin gManagemen tSystem s (1,2 ,3 an d 4),se x(male , femalean dox )an dseason s (1,2 ,3 an d 4),th elogisti c regressionuse sth ereferenc evalu et odetermin eth evalue so f ßfo reac ho fth eothe rvalue so fth eindependen tvariabl e beingevaluated .Covarianc ematrice san dvalue so f ß provide thestatistica lrelation sbetwee nal lvalue so fth eindependen t variable.

Results.

Table1 provide sspecifie d informationo nth eremova l reasonsuse dfo rth eanalyse so fwhic hth eresult sar egive ni n table1 .Slaughter ssee mt otak eplac ei nth emajorit yo fcase s ifanimal sar eol do rsick .Mos tslaughter sca ntherefor eb e regardeda semergenc y slaughters.Fo rthi sreaso nth emortalit y andslaughte r figureswer epoole d intabl e1 an dfigur e2 .

58 Table1 . Reasonsfo rremova lo fanimal sfro mtraditionall y managedcattl eherd sfro mfou rGrazin gManagemen t Systemsi nth eWester nProvinc eo fZambia ,a sfoun d inth eperio d1/4/8 6til l31/3/88 .

GrazingManagemen t System: 1 2 3 4

Removal reason no. % no. % no. % no. %

Sold: 101 50 78 81

-no tspecifie d 25.7 16.0 21.8 23.5 - locallyfo rbreedin g 5.0 2.0 6.4 4.9

- locallyfo r 13.9 - 7.7 8.6 slaughter

-t oprivat etrade r 29.8 32.0 37.2 27.2 -t oinstitutiona l 25.7 50.0 26.9 35.8 trader Slaughtered: 33 19 32 32

-no tspecifie d 6.1 5.3 - 3.1 -ol dage ,sickness , 66.7 63.2 71.9 84.4 weakness -fo rceremon y - 10.5 3.1 3.1 -fo rmeat ,mone y 27.3 21.1 25.0 3.1 -fo rothe r purposes - - - 6.3

Died: 146 84 143 93

-no tspecifie d 27.4 39.3 14.0 32.3

-mea t consumed,sol d 47.9 44.0 66.4 49.5

-mea tdiscarde d 24.7 16.7 19.6 18.3

Overall totalnumbe r 280 153 253 206

Figure1 show sa descriptiv eimag eo fth eproportio no f thefemal ean dmal ecalve ssurvivin gth efirs tmonth ,th efirs t threemonths ,th efirs thal fyea ran dth efirs tyea rafte r birthi nth efou rgrazin gmanagemen tsystems ,fo rmal ean d femalecalves .Difference sar emos tprominen ta tth eag eo f1 2 months,bot hi nfemal ean dmal ecalves .Onl yth edifference si n thefemal ecalve ssho wsignifican tdifference si nx 2-analysis. InGrazin gManagemen tSyste m (GMS)1 th esurviva lrate sa tth e ageo fon eyea rsee mlowe rtha ni nth eothe rsystem sdescribed ,

59 Figure1 . Survivalrate so fcalve si nher dgroup sconsistin go f herdsfro mfou rGrazin gmanagemen tSystem so fWester n Province,Zambia ,betwee n0 an d36 5day so fage ,ove r theperio d1/4/8 6til l31/3/88 .

kW» eafc«a

100

VJ^^*W 90 I * - -•- *Mm2 ! 70

0 « ii it ww of a*

bothfo rmal ean dfemal ecalves .Th eline srepresentin gth e survivalrate so fth efemal ecalve si nGM S2 ,3 an d4 ar e consistentlyhighe rtha nthos eo fmal ecalve si nal lsystems , andtha to ffemal ecalve si nGM S1 .Th esurviva lrate so fth e malecalve san do fth efemale si nGM S1 sta yapproximatel yi n lineuntil lth eag eo f6 months .Th esurviva lrate so fmal e calvesi nGM S2 ,3 an d4 ar eles sstee pove rth elas t6 months , whiletha to fth efemal ecalve si nGM S1 i spracticall ya s steepa sbefor eth eag eo f6 months .Tha to fth emal ecalve si n GMS1 i smuc hsteepe ri nth elas t6 months .A tth esam etim e thesurviva lrat eo ffemal ecalve sa tth eag eo fon eyea ri s significantlyhighes ti nGrazin gManagemen tSyste m2 .Thi si s notsee ni nth emal ecalves .

Intabl e2 th eresult so fth elogisti cregressio nanalysi s ofth eremova lfigure sar egiven .I fvariou svalue so f independentvariable sdiffere d significantly,thi si sindicate d bydifferen tcharacter si nth esuperscript .I nth emortalit y andslaughter ssignifican t influencescoul donl yb efoun dfo r thesex ,th eag ean dth eherd ,whil ei nth esale sfigure s differencescoul dals ob esee nfo rGrazin gManagemen tSyste m andfo rtranshumanc eo rsedentarism .Increasin gag eseem st o havea decreasin g influenceo nth echanc eo fdyin go rbein g slaughtered,whil eth echanc eo fbein gsol dincrease swit hage .

Infigur e2 th eresult so fpar to fa mode lo flogisti c regressionanalysi si sshown ,i nwhic hmortality ,slaughte ran d salesfigure sar eanalyse da sproportion so fth eremove d

60 Table 2. Statistical evaluation of removal figures of cattle from the Western Province, Zambia, calculated over the period 1/4/86 till 31/3/88.

Deaths andslaughter s Sales * variable N % f s.e. % ß s.e. intercept 6424 -3.0686 0.4119 -4.0732 0.7975 GMS1 1940 9.2 0.2651 0.4088 5.2 0.55268 0.7861 GMS2 1369 7.5 -0.0475 0.3368 3.7 0.0430ab 0.6580 GMS3 1774 9.9 0.1346 0.2063 4.4 -0.4052b 0.3490 GMS4 1342 9.3 réf. 6.0 ref.ab S 3625 9.5 0.2086 0.3510 5.1 0.8768a 0.7092 T 2800 8.4 réf. 4.5 ref.b F 3917 8.8 0.7459s 0.1395 2.8 -1.92043 0.2520 M 1064 16.3 1.3170b 0.1567 4.0 -0.5836b 0.3416 0 1443 4.6 ref.c 11.0 ref.c periodI 3341 9.4 ref. 4.7 ref. periodI I 3084 9.0 -0.1169 0.0980 5.0 0.0366 0.2049 Ageou to fher di n days 9.1 -0.00021 0.0000 4.8 0.00081 0.0001 Herd effect (rane lorn) 0.32821 0.0725 0.56231 0.1491

Valueswit hdifferen tletter si nth esuperscrip tdiffe rsignificantl y(p<0.05) . Effectsignifican t(p<0.05) . GMS= Grazin gManagemen tSyste m

animals only. This was done in order to evaluate whether an influence of seasonal variation on removal figures could be identified. The odds ratios of the pooled mortality and slaughter figures are shown in the figure, together with the total number of animals removed because of death, slaughter or sale in the respective seasons. The complete model also contained most of the variables used in table 1. Significant differences are found in all cases. The level of the mortality/slaughter figure in period I, season 1 is used as reference value.

61 Figure2 . Parto fa logisti cregressio nmode luse d forth e evaluationo fseasona leffect so nmortalit yan d slaughter intraditionall ymanage d cattlei nth e WesternProvince ,Zambia ,ove rth eperio d1/4/8 6til l 31/3/88.Th eris kpatter ni sdisplaye d asa soli d linean dshoul db erea dagains tth elef tY-axis .Th e valueo fperio d I/season 1i suse da sreferenc e (Odds Ratio- 1). Theinterrupte d linegive sth etota l numbero fanimal sremove d (throughdeath ,slaughte r andsale )i neac hperiod/seaso n andshoul db erea d againstth erigh tY-axis .

Riak pattern

Odds Number ratio removed

.9 S

80 1-2 1-3 1-4 1-1 H-2 11-3 11-4 n-1 Period - season

Discussion.

Apart fromestablishin gtha tmos t slaughtered animalswer e slaughtered foremergenc yreasons ,tabl e1 als oshows ,tha tth e numbero fanimal ssol dwa sfa rsmalle rtha nth enumbe rtha t diedo rwa sslaughtered .Thoug hal lmea to fslaughtere d animals andmos to fth emea to fanimal stha tdie d isconsume do rsold ,

62 theseanimal sshoul db eregarde da slosses ,becaus eth erevenu e fromthes eanimal si susuall yconsiderabl y lesstha ntha to f animalssol d (Beerling,1986) .Sale s"outsid eth esystem" ,t o traderswh owil li npracticall yal lcase sdestin eth eanimal s forslaughte routsid eth evillage ,mostl yth eabbatoi ri nth e maintow no ri nabbatoir soutsid eth eprovince ,ar eth emos t importantproportio no fth esales .Loca lsales ,eithe rfo r slaughtero rbreeding ,ar eo fvirtuall yn oimportance .A sfa r asgeneratio no frevenu ei sconcerned ,th eanimal ssol dint o thecattl etrad ear eth emos t importantfactor .

Figure1 show stha tth eaverag esurviva lrate so fcalve s afteron eyea rrang ebetwee n6 5an d9 0percent .Th esurviva l ratesafte ron eyea rsee mslightl yhighe rfo rfemal eanimal si n allGrazin gManagemen tSystem s (GMS).Surviva lchance sfo r calvesi nGM S1 see msmalle rtha ni nal lothe rsystems .Th e survivalrat eu pt o6 month so ffemal ecalve si scomparabl et o thato fmal ecalve si nal lsystems ,whil etha to fbot hmal ean d femalecalve si nGM S1 dro pconsiderabl ybelo wtha to fmal e calvesi nothe rsystems .

Asca nb esee nfro mtabl e2 ,th emortalit yan dslaughte r figuresar esignificantl yhighe rfo rmale san dfemale stha nfo r oxen.Cow sar eo naverag ekep ti nth eher dmuc hlonge rtha n oxen.Thei raverag eag ei stherefor ehigher ,whic hma yb eth e reasontha tmortalit y ishighe ri ncows .Th ehig hmortalit y ratei nbull smigh tsugges ttha tselectio no fbull st ob e castrated ispartl ybase do nth egenera lhealt ho fth eanimals . Theweake ran dmor evulnerabl eanimal sar eno tcastrated ,bu t havea bigge rchanc eo fdying .Significan tdifference sbetwee n thesexe sar eparticularl y causedb yth emortality .I f slaughterfigure sar eevaluate d separatelyn osignifican t differencesbetwee nth esexe sar efound .Al lsexe ssee mt ohav e asmuc hchanc eo fbein gslaughtere d inemergency .Anothe r significantdifferenc ebetwee nemergenc y slaughtervalue stha t isno tfoun di nth ecombine d figurei stha tbetwee nth e periods.I nperio d Ith enumbe ro fanimal sslaughtere dwa s highertha ni nperio dI I (2.2% versu s1. 7 %,th eaverag e percentageslaughtere dbein g1.8) .I fevaluate d separately,th e decreasing influenceo nmortalit yo fincreasin gag ei ssee n again,bu tth eslaughte rvalue ssho wa nincreas ewit h increasingage .Bot har esignifican t influences.Th ereaso nfo r theincreasin ginfluenc eo fincreasin gag eo fth eOdd sRati o forslaughte ri nemergenc y is,mos tlikely ,tha ti fcalve sar e dying,th edecisio nt oslaughte rthe mi sles softe ntake ntha n ifadul tanimal sar edying ,becaus eth emea to f (young)calve s israrely ,i fever ,eaten .

63 Theinfluenc eo fag eo nth eO Rfo rdeat han demergenc y slaughteri ssignificant .Th efac ttha tth evalu ei snegative , iscause db yth ehig hcal fmortalit ya si sillustrate db yth e survivalrate si nfigur e1 .Ther ei sa significan t influenceo f theher di nwhic hth eanimal sar ebased .Thi sindicate stha t thewa y inwhic hth eher downe rgoe sabou thi smanagemen tma y beo fimportance .Analysi so fday-to-da ymanagemen tdecision makingrelate dt oth eproductiv eperformanc ei nindividua l herdsma yproduc eusefu lextensio nmaterial .Thi scoul drelat e todecision so ngrazin garea st ob echosen ,th eamoun to ftim e spento ngrazin gan do nkraaling ,th emomen to fth eda ytha t animalsar ereleased ,th emomen tthe yar emilke dan dth eamoun t oftim eth ecal fi sallowe dt osuckle .Th esize ,amoun to f spacepe ranima lan dth econstructio no fth ekraals ,a swel la s ofth eyoungstoc kkraal so rpen sma yb efactors .Environmenta l differenceso fa mor eloca lnatur etha nthos edescribe da s GrazingManagemen tSystem sma yo fcours eals ob eo fimportance . Analysiso fth eway sher downer shandl ethei renvironmen tcoul d alsogiv einformatio n forus ei nextension .

Amortalit y figureo f5 % fo radul tanimal si sgive nb y Perrye tal . (1984).Thi si sslightl ylowe rtha nth evalu e foundi nth epresen tstudy .Th ecal fmortalit y figuresshow ni n figure1 ar elowe rtha nthos ementione db yBesse lan dDaply n (1977)an dLutke-Entru p (1971).Besse lan dDaply n (1977)onl y mentiona nestimate dcal fsurviva lrat eu pt oth eag eo fon e yearo f6 5% .Th ecorrespondin gmortalit y ismuc hhighe rtha n wasfoun di nth eher dmonitorin gprogramme .Lutke-Entru p (1971) indicatestha t3 0% o fth ecalve sdi ewithi na fe wdays .Th e datacite d fromth ethre esource smentione dwer ecollecte d throughquestionnai rsurveys .I na compariso nwit h3 othe r Africanbreed sa tth eCentra lResearc hStatio na tMazabuka , Zambia,a weanin gpercentag eo f7 4% ,correspondin gwit ha cal f mortalityo f2 6% wa sreporte d forth eBarots ebree d (Thorpee t al.,1980a ,Thorp ee tal. , 1980b).Th eanimal sgraze dth e plainso fth eKafu erive rpar to fth eyea ran dth eadjoinin g uplanddurin gth eremainin gperiod .Th estatio ni slocate da t analtitud eo f99 0metres .I ncomparabl estudie sa tMochipap a ResearchStation ,a ta naltitud eo f137 0metres ,th e environmentwa sconsidere d lessproductiv etha ntha ta t Mazabuka.Th eGrazin glan dconsiste do funimprove daci d zandveldwit hlarge ,periodicall ywaterlogge ddepressions .I n theseles sfavourabl eenvironment sth ecal fmortalit y inth e Barotsebree dwa s46. 2% (Thorpee tal. , 1981).Perr ye tal . (1984)an dRevei l (1975)fin dmortalit yfigure stha tar e comparablewit hthos efoun da tpresent ;a cal fmortalit yo f2 0 %an d19. 4% respectively .

64 Inth esale sfigure ssignifican tdifference sar eonl y foundbetwee nGrazin gManagemen tSystem s1 an d3 .Thi sma yb e relatedt oth eleve lo factivit yo finstitutiona lcattl ebuyer s anddifference si nth einfrastructur ebetwee nthes esystems . Thesale spercentag ei nth etranshuman therd si ssignificantl y lowertha ni nth esedentar yherds .Thi sma ymainl yb ecause db y thehig hsale spercentag ei nGrazin gManagemen t4 ,i nwhic h practically allherd sar esedentary .Th ereaso nfo rth e relativelyhig hsale spercentag eis ,tha tth eare ai sver ydr y andth eresult so fgrowin gcrop sar eofte ninsecure ,makin gi t necessaryt ogenerat emone yt obu yfood .

Increasingag ehas ,i nth esale sfigure ,a soppose dt oth e mortality,a nincreasin ginfluenc eo nth eOR .Farmer sten dt o chooseol danimal sfo rsale ,an dpreferabl yoxen .Youn g animals,calve si nparticular ,ar ehardl yeve rsold ,an d certainlyno tfo rslaughte routsid eth evillage .I fanimal s stillhav et oprov ethei rabilitie san dar efertile ,th efarme r willprefe rt okee pthem .Risk-avertin gbehaviou r isbes t servedwit hkeepin ga smuc ha spossibl ereproductiv epotentia l inth eher d (Matthewman,1980) .

Perrye tal . (1984)mentio na nofftak eo f4 % ,consistin g of2 % loca lslaughter ,an d2 % sales .Th eslaughte rfigur ei n thisstud yi sapproximatel yth esame ,th epercentag eo fanimal s soldt otrader si showeve raroun d4 % .Th eoveral lsale s percentagei nth eprovinc eseem st ob erising .Thi si s consistentwit hth erisin gtren di nth eannua lcattl esale s fromth eprovinc e (VanKlin ke tal. , 1990).

Evaluatingth eremova lfigure sdu et omortalit yan d slaughtera sa proportio no fth etota lnumbe ro fanimal s removedbecaus eo fdeath ,slaughte ran dsale ,i norde rt o assessth epossibl einfluenc eo fclimat ean dseaso no n mortalityan demergenc yslaughters ,a swa sdon et oobtai nth e logisticregressio nresult spartl yshow ni nfigur e2 ,i st o someexten tartificial .Als oth enumbe ro frecord sinvolve di n themode li sconsiderabl y smaller.Therefor ea probabilit y level (p<0.10)wa schose nothe rtha n0.0 1 or0.05 .

Theodd srati ofo rmortalit y (andemergenc y slaughter)wa s foundt ob ehighes tfo rseaso n3 ,th eho tdr yseason , particularlydurin gperio d I.I nperio d IIth e mortality/8laughterfigure si nseaso n3 an d4 ar ei nth esam e range.I nseaso n3 th econstrain to nfodde ravailabilit yma yb e themos timportan tcause .Th eO Ri nseaso n3 o fperio d Ii s veryhigh ,compare dt oal lothe rO Rvalues .Th epoo rwe tseaso n

65 precedingperio d Ima yb eth ecaus eo fthis .Climati cvariatio n betweenyear sar elikel yt ocaus eth edifferenc ebetwee nth e twoperiods .I tdoe showeve rno texplai nclearl ywh yth eO Ri n theearl yrain yseason ,seaso n4 ,o fperio d Ii sconsiderabl y lowertha ni nseaso n3 ,an dals olowe rtha ni nseaso n4 o fth e subsequentperiod .Th egrazin gmanagemen tpractice sma yals o havebee na ninfluence .Relativel yhig hrainfal lfigure sfo r instance,providin ggoo dregrowt ho fth evegetation ,an d thereforegoo dsurviva lcondition sfo rth elivestock ,ma ycaus e constraint forherd stha tar ehighl ydependen to nfloodplai n grazing,particularl y inGrazin gManagemen tSyste m 1,becaus e thefloodplain swoul db efloode dan dtherefor einaccessibl efo r a longertime .I twa showeve rno tpossibl et oevaluat eth e relationbetwee nperiod ,seaso nan dGrazin gManagemen tSyste m further,becaus eth eproportion swoul dbecom eto osmal lfo r statisticalevaluation .

Inth elogisti cregressio nmode luse d forthi sfigure ,th e valueso f ß forseasona leffect so nsale sfigure sar eexactl y therevers ea sthos efo rmortalit yan dslaughter .Th esale s figuresar emostl yhighes ti nseaso n1 o feac hperiod .Thi si s thetim eo fth eyea rtha tfarmer shav euse dmos to fthei r storedstappl ecro pan dar ewaitin gfo rth ene wharvest .Th e salesfigure sma yb estrongl yrelate dt oth ecas hnee d resultingfro mth enecessit yt obu yfoo di nthi stim eo fyear . Ifth ecroppin gseaso nha sbee npoor ,th esale spea kwoul db e higheran dwider .Th epoo rrainfal learl yi nperio d I,causin g thehighe rodd srati ofo rmortality/slaughter ,ma ytherefor e alsob eth ecaus efo ra highe rsale sleve li nseaso n1 o f periodI .

Inconclusion ,i tca nb estate dtha tth enumbe ro fanimal s lostthroug hdeat han dslaughte ri sfa rlarge rtha nth enumbe r sold.Decreasin gth emortalit y figure,mos tnotabl ytha to f calves,woul dmea na nimportan t improvemento fth eperformanc e ofth eherds .Thoug hth elimitation so fth eGrazin gManagemen t Systemi nwhic hth eherd sar elocate dan dth eclimat edictat e considerablyth epossibilitie so ffarmer st oadjus tthei rways , thefac ttha ta ninfluenc eo fth eherd ,an dtherefor eth e managemento fth eindividua lherd swa sidentified ,make si t worthwhilet oasses sindividua lher dperformanc ean dmanagemen t inorde rt oderiv eextensio ninformatio nabou tcopin gwit hth e environmenti nth emos tfavourabl eway .

Acknowledgements. Theauthor swis ht othan kth eDirecto ro fth eDepartmen to f Veterinaryan dTsets eContro lService sfo rhi spermissio nt o

66 submit this paper for publication. We alsowis h to thank the project leader of the Livestock Development Project Western Province, Dr.R.C .de Rooij, for his contributions, and for providing the logistic possibilities to carry out the study.

Literature.

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2. BeerIing ,M.L.E.J . (1986).Acquisitio nan dalienatio no fcattl ei nth e traditional rural economyo fWester n Province, Zambia.MAUD , Government Printer, Lusaka, Zambia. 3. Beerling, M.L.E.J., (1991).Th e advantageo fhavin g cattle.Dept .o fVet . and Tsetse Contr. Serv., Mongu, Zambia.Departmen t ofVeterinar yan dTsets e Control Services,Mongu , Zambia,RD PLivestoc k Services, Zeist, TheNetherlands .

4. Bessell, J.E., and M.G.Daply n (1977).Dairyin g inZambia - thetraditiona l sector.Un .o fNottingham , U.K.

5. Brumby, P.J. (1986). ILCAan dfoo d production inAfrica .Worl d Animal Review60 , 33-37. 6. Brumby, P.J.,an dJ.CM . Trail (1986).Anima l breedingan dproductivit y studies inAfrica . ILCA Bull.23 ,23-27 . 7. Dicko,M. ,(1990) .Th erol eo fth e familyi ntraditiona l cattle keepingi n Africa. Proc.6t hInt .Conf .AITVM , Wageningen, theNetherlands ,28t h Aug.-1st Sept. 1989. 8. Gluckman,M .(1941) . The economyo fth eCentra l Barotse Plain.Rhodes-Livingston e paper no.7. 9. Horn,L .va n(1977) .Agricultura l historyo fBarotseland . In:R .Palme r& N . Parsons, eds.:Th eroot so frura l povertyi nCentra l andSouther n Africa. Heinemann, London.

10. Hosmeran dLemesho w (1989).Applie d logistic regression. JohnWile yan d Sons, New York, USA. 11. Jeanes,K. ,an dR.T.M .Baar s (1990).A rangelan d resource appraisalo fWester n Province, Zambia. Report Department ofVeterinar y and Tsetse Control Services, Mongu, Zambia. 12. Klink, E.G.M,van , J.J.F.M.Corten , and D.M. Kalokoni (1994). Herd monitoringi n traditional cattle husbandryo fWester n Province, Zambia, I:Organisationa l design, datamanagement , descriptive aspects,an dth eher d structureo ftria l herds infou r Grazing Management Systems.(submitted)

13. Klink, E.G.M,van , M.M. Kauambua and D.M. Kalokoni (1990). The cattle population of theWester n Province, Zambiao nth ebasi so fth eAnnua l Livestock Census 1987, 1988, 1989.Departmen t ofVeterinar yan dTsets e Control Servicesan dRD P Livestock Services b.v.,Wester n Province, Zambia.

14. Lutke-Entrup,J .(1971) . Limitationsan dpossibilitie so fincreasin g market productiono fpeasan t African cattle holders inWester n Province, Zambia. Lusaka, Zambia.

67 15. Martin,S.W. , A.H.Mee kan dP .Willeber g (1987).Veterinar y Epidemiology. Principlesan dmethods .Iow aStat eUniversit yPress ,Ames , Iowa,USA . 16. Mason, J.L., andJ.P .Maul e (1960).Th e indigenous livestocko feaster nan d southernAfrica .Technica l Communication no. 14,CAB ,London ,UK . 17. Matthewman,R.W . (1980).Anima l diseasecontrol ,Zambia , cattleproductio nan d health.FA O reportAC:DP/ZAM/77/002 . 18. Perry,B.D. ,B .Mwanaumo , H.F.Schels ,E .Eiche ran dM.R .Zama n (1984).A stud y ofhealt h andproductivit y of traditionallymanage d cattle inZambia .Prev .Vet . Med.2 ,633-653 . 19. Peters,D.U . (1960).Lan dUsag e inBarotselan d (ed.N .W . Smyth).Rhodes - Livingstone Institute,Lusaka ,Zambia . 20. Puzo,B . (1977).Pattern so fman-lan d relations.In :M.A.J .Werger ,ed. : Biogeographyo fecolog yo fSouther nAfrica .De nHaag ,Th eNetherlands . 21. Rennie,J.K . (1982).Smal l scalecattl edevelopmen t inZambia :problem san d prospects.Zambi a Cooperative Federation, Lusaka,Zambia . 22. Reveil,S.G .(1975) . Fertilityan dneonata l lossessurvey ,a report basedo n observationsmad e in197 3an d 1974.Dept .o fVet .an dTsets eContr .Serv .Lusaka , Zambia.

23. Roberts,A . (1976).A Historyo fZambia .Heinemann ,London ,U k (Repr. 1981). 24. Rooij,R.C .de ,an dA.P .Woo d (1990)."Wh oPay s theBill" :Toward s Sustainable CattleDevelopmen t inWester nZambia .Proc .6t h Int.Conf .AITVM ,Wageningen , the Netherlands,28t hAug.-1s t Sept.1989 .

25. Thorpe,W. ,D.K.R .Cruickshan k andR .Thompso n (1980a).Geneti c andenvironmenta l influenceso nbee f cattleproductio n inZambia . 1.Factor saffectin g ueaner production fromAngoni ,Barots ean dBora ndams .Anim .Prod .30 ,217-234 . 26. Thorpe,W. ,D.K.R .Cruickshan kan dR .Thompso n (1980b).Geneti c andenvironmenta l influenceso nbee f cattleproductio n inZambia .2 .Liv eweight s forag eo f purebred and reciprocally crossbred progeny.Anim .Prod .30 ,235-243 .

27. Thorpe,W. ,D.K.R .Cruickshan k andR .Thompso n (1981).Geneti c and environmental influenceso nbee f cattleproductio n inZambia .4 .Weane r production from purebred and reciprocally crossbreddams .Anima l Production33 ,165-177 .

28. Wood,A.P . (1986).Researc h proposal:Polic y implications ofsocio-economi c aspectso fcattl ekeepin g inWester nProvince ,Zambia .Th epolytechnic , Huddersfield.Unite d Kingdom.

(submitted for publication.)

68 2.3.Her dmonitorin gi ntraditiona lcattl ehusbandr yo fWester n Province,Zambia ,III :reproductiv eperformance ,lactatio n intervalsan dgrowth .

E.G.M.va nKlink 1,J.J.F.M .Corten 1,S.H .Wiersma 1 andG.C . Bbalo1.

Introduction.

Intraditiona l livestockmanagemen tsystem si nAfrica , ruminantsdepen dentirel yo nnatura lpasture sfo rthei r maintenance (Gow,1987 ,Sandford , 1983).Th equalit yo fthes e pastureshighl ydepend so nclimati ccondition s ('t Mannetje, 1981,Pratt ,1984) .Dr yseason sca nproduc elon gperiod si n whichth equalit yan dquantit yo fth efoo di sbelo wmaintenanc e standards (Coppocke tal . 1986),havin ga negativ einfluenc eo n performancei nterm so fweigh tgai n (Mosie tal. ,1976 )an d reproduction (Chandler,1971 ,Matthewman , 1980).Especiall y conceptioni saffecte dnegativel y (Wilson,1985) .Thi si sals o causedb yth efac ttha tth eintak eo ffodde ro fpoo rqualit yi s depressed (Ketelaarsan dTolkamp ,1991) .Th emanagemen t practiceo ftranshumanc ei sa wa yo fattemptin gt ocounterac t parto fth enegativ eclimati c influences (Dicko,1990) . Inth e WesternProvinc eo fZambia ,transhumanc eove rdistance so fu p to4 0Km .take splac ei npar to fth ecattl epopulatio n (Jeanes andBaars ,1990 ,va nKlin ke tal. , 1990).Th ecattl eindustr y inWester nProvinc ei spar to fa mixe dfarmin gsystem ,i nwhic h cattlepla ya nimportan trole ,throug hth eprovisio no fdraugh t poweran dmanur e (Puzo,1977 ,Peters ,1960) .

A surveywa scarrie dou ti nth eprovinc et oassess , whetherth eus eo fa longitudina lher dmonitorin gsyste m (Van Klinke tal. ,1994 )allow sth eidentificatio no fenvironmental , seasonalan dmanageria linfluence so nproductivity .Th esurve y wascarrie dou tb yth eLivestoc kDevelopmen tProjec tWester n Province (DeRooi jan dWood ,1990) . Inthi spape rth eresult s relatedt oweigh tan dreproductiv eperformanc ear epresented .

Materialsan dmethods .

Herds.

4 'Department of Veterinary and Tsetse Control Services, Livestock Development Project Western Province,P.O.Bo x910034 ,Mongu ,Zambi a

69 Atota lnumbe ro f5 2herd swit happroximatel y 6000hea do f Barotsecattle ,a lon ghorne dSang abreed ,wer einvolve d ina twoyea rmonitorin gprogramme .No tal lherd shav ebee n monitored forth eful lperio do f2 years .I nth efirs tyear ,a totalo f4 5herd swer emonitored ,i nth esecon dyea r3 4(Va n Klinke tal. , 1994).

Area.

Theare ai nwhic hth estud ywa scarrie dou tha sbee n describedb yVa nKlin ke tal. ,1994 .Th eKalahar isands ,tha t covermos tpart so fth eprovince ,ar efo rth elarge rpar t relatively infertile (Verbooman dBrunt ,1970) .Fou rGrazin g ManagementSystem s (GMS)wer edistinguishe do nth ebasi so f differencesi nmanagement ,fodde ran dwate ravailabilit y (Jeanesan dBaars ,1990 ,Va nKlin ke tal. , 1994). InGM S1 an d 2transhumanc ei smos tcommon ,whil ei nGM S3 an d4 sedentaris m ispredominant .Transhumanc ei nGM S1 an d2 diffe ri nterm so f thelengt ho fth eperio dspen ti nth efloodplain san do nhighe r grounds.GM S3 an d4 diffe rpredominantl y interm so fwate ran d fodderavailability .

Climate.

Theclimat eo fth eare ai scharacterise db ya we tseason , whichstart saroun dth emonth sOctober/November ,an dwhic h laststil learl yApril .The na dry ,an dconsiderabl ycolde r seasonstarts ,becomin ghotte ri nth ecours eo fJuly .Fo rth e purposeo fanalysi so fth einfluenc eo fth eseason ,th eyea r wasdivide di nfou rthre emont hperiods ,parale lwit hth e changeo fseason stakin gplace .Seaso n1 ,th elat ewe tseason , runsfro mJanuar yt oMarch ;seaso n2 ,th ecoo ldr yseason ,fro m Aprilt oJune ;seaso n3 ,th eho tdr yseason ,fro mJul yt o September;seaso n4 ,th eearl ywe tseaso no rgrowin gseason , fromOctobe rt oDecember .

Monitoringprocedure san dcalculations .

Themonitorin gprocedure san dth emanne ri nwhic hprimar y calculationso fth eparameter sinvolve dwer ecarrie dout ,base d onth ePanacea (c)2genera lpurpos edat amanagemen tprogramme , havebee ndescribe db yVa nKlin ke tal. ,1994 .Th estatisti c

2 (c)Pa nLivestoc kService sLtd. ,Readin gUK .

70 programmeDbsta t

Results.

Intabl e1 th emodel sar epresente dtha twer euse dfo rth e evaluationo fgirt hmeasurement san do fth elactatio ninterval s indays .Fo rth esak eo fclarit yonl ythos epart so fth emodel s used,i nwhic hsignifican tdifference swer efound ,hav ebee n displayed inth etable s3 ,4 an d5 .

Table2 give sdescriptiv estatistic so nth efemal eanimal s present inth eherd san dth enumbe ro fcalving stha tha sbee n recordeddurin gth esurvey .A relativel y largeproportio no f theanimal si si nth eherd sfo rshor tperiods .Thes eanimal s include,apar tfor mdeaths ,slaughter san dsales ,als o transfersbetwee nherd sfo ra variet yo freasons .Thi sfigur e mayb eo finfluenc eo nth epercentag eo fanimal stha tcalv ei n theherd .I nGrazin gManagemen tSyste m4 thi spercentag ei s low, combinedwit ha hig hproportio no fanimal stha tsta yi n theher d forshor tperiods .Simpl edistributio nstatistic s(% 2- analysis)show stha tsignifican tdifference sbetwee nsystem s seemt oexis t inth eproportio no fanimal stha tmov ebetwee n

71 Table 1. Variables inmodei so fAnalyse s of variance used for the evaluation of someproductivit y traits in traditionally managed cattle inth eWester n Province of Zambia.

lactation intervalsfo r thecalvin g intervals,o n the girth measurementsi n complete lactationso f thebasi so fal lcomplete d threeag egroups . cows that weremilke dan d lactationsan da saffecte d correctedfo rag ean da s of which thecalve s were by: affectedby : weanedan da saffecte d by:

Parity Parity Grazing Management System Grazing Management System Grazing Management System (GMS) (GMS) (GMS) Sex Calving season Calf weaned/dead(A ) Season „ GMS*Parity Cowm iIked/no t milked(B ) Herd movement practice GMS*Calving season Calving season System*season Removal age calf(C ) (A*B) (A*C)

Transhumanceo rSedentaris m

herds, the percentage of animals present that have calved during the survey,th e proportion of these that calved once, more than once,o r that calved three times during the survey period, and between theproportio n of first calvings before the ageo f fouryears .

Figure 1show s the distribution of the calving intervals on the basis of their duration.A s canb e seen from figure la the majority of the calving intervals has a duration of between 12 and 22month s (around 60 %), with a relatively wide peak between 12 and 16month s duration,an d a steadilly decreasing proportion untill aduratio n of 22month s (from around 7t o around 3 %). Around 24month s calving interval duration a relatively sharppeak , including around 21 %o f all calving intervals, can be found. Figure lb shows,that with the exception of Grazing Management System 1,th e Grazing Management Systems do not seem to differ importantly as regards the distribution of calving intervals according to their duration. InGrazin g Management System 1however , the proportion of calving intervals with aduratio n of between 12 and 18month s isrelativel y low,compare d to the others,an d the proportion with aduratio n of between 24 and 30month s is relatively high compared to the others.N o differences were found between the proportions of the calving intervals between 18an d 24month s and above 30months .

72 Table2 . Descriptivequantitativ edat ao ncalving si ngroup s ofcattl eherd sfro mfou rGrazin gManagemen tSystem s inth eWester nProvince ,Zambia .

GrazingManagemen tSyste m 1 2 3 4 A.Tota lnumbe ro ffemale s 858 433 552 517 presentdurin g thesurve y oldertha n2 year s Numberpresen t forles s 181 (21.1) 76 (17.6) 99 (17.9) 125 (24.2) thanon eyea r (Xo fA. ) B.Tota lnumbe ro f 737 371 518 378 calvingsdurin g thesurve y C.Tota lnumbe r ofanimal s 474 (55.2) 202 (46.7) 299 (54.2) 206 (39.9) thathav ecalve ddurin g thesurve y( Xo fA. ) Number ofanimal stha t 234 (49.4) 61 (30.2) 118 (39.5) 48 (23.3) calvedonc edurin gth e survey (Xo fC. ) Numbero fanimal stha t 240 (50.6) 141 (69.8) 181 (60.5) 158 (76.7) calvedmor etha nonc e during thesurve y( %o f C) Numbero fanimal stha t 23 (4.9) 28 (13.9 38 (12.7) 24 (11.7) havecalve dthre etime s during thesurve y (Xo f C.) D.Tota lnumbe r offirs t 183 164 183 149 calvingsrecorde d Noo f recordedfirs t 131 (71.6) 109 (66.5) 133 (72.7) 121 (81.2) calvingsbefor eth eag eo f fouryear s( Xo fD. )

Table3 show sth evalue sfoun di npar to fth emodel suse d forth elactatio nintervals ,onl yfo rthos eanimal stha twer e milkedan dtha tweane dthei rcalf .I nal linterval ssignifican t differencesbetwee nGrazin gManagemen tSystem s (GMS)wer e found.Th ecalvin ginterva lwa ssignificantl ylonge rtha ni n anyo fth eothe rsystem si nGM S1 .I nth einterva lcalving - startmilkin g significantdifference sexiste dbetwee nGM S1 an d thesystem s2 an d4 ,i nwhic htha to fGM S1 wa sconsiderabl y longer (124day sa soppose dt o5 1an d8 0day srespectively) . Thato fGM S2 wa ssignificantl yshorte rtha ntha to fGM S1 an d 3.Th elengt ho fth emilkin gperio dwa sshorte ri nGM S3 (22 2 days)tha ni nGM S1 an d2 (over30 0days) .GM S2 ,showin gth e longestmilkin gperiod ,als odiffere dsignificantl yfro mGM S4 . Theweanin gag ei sshortes ti nGM S3 ,differin gfro mGM S1 an d 2,bu tno tfro mGM S4 .GM S4 di dno tdiffe rfro mGM S2 .I nth e intervalbetwee nweanin gan dth enex tdelivery ,onl yGM S2 an d 3differre dsignificantly .Anothe rimportan t influencei nsom e

73 Figure1 . Thedistributio no frecorde dcalvin ginterval si n traditionallymanage dcattl efro mth eWester n Provinceo fZambia ,o nth ebasi so fthei rlength .

a.Distributio no fth eduratio no fal lcalvin ginterval s recorded.

1 , JTi n i« n " -1 fi _ 1 1 NO. or cafe. f: f 1 httnwJs 1 J -i 1 k. 12 11 1 24 30 >31 bmgflh ef caMno htt«mala in montra

b.Distributio no fth eduratio no fcalvin ginterval sfro m fourGrazin gManagemen tSystem si nsi xmont hblocks .Th e valueso fth ecalvin ginterval so f1 2t o1 8month san d2 4 to3 0month sparticularl yGrazin gManagemen tSyste m1 sho w significantdifference sfro mth eexpecte dvalu ei nX 2 analysis (p<.005).

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CI m ai v ai C S E 3 rH •*- Ol V NCW CO J3 CO C IA id e- CO >« > H (3X0) ofth einterval sprove dt ob eth eseaso ni nwhic hth eanima l calved.Th einterva lbetwee ncalvin gan dstar tmilkin gi s significantlyshorte rwhe nth ecal fwa sbor ni nth eearl ywe t season,o rth egrowin gseason ,tha ni fth ecal fwa sbor ni nth e earlydr yseason .Th elengt ho fth emilkin gperio dwa sals o significantlyshorte ri fth ecal fwa sbor ni nseaso n2 tha ni f itwa sbor ni nseason s3 an d4 .I nth eweanin gag esignifican t differenceswer eonl yfoun dbetwee ncalve sbor ni nseaso n1 an d 2,i nwhic htha to fcalve sbor ni nseaso n1 wa sth elongest . Parityprove dt ob eo fsom einfluenc eonl yo nth ecalvin g interval;Th ecalvin ginterva lo fth efirs tparit ywa slongest , buti tdiffere d significantlyonl yfro mparit y4 ,whic hha dth e shortestduration .

Intabl e4 par to fth eresult so fth emode luse d forth e evaluationo f71 9calvin ginterval so fwhic hcomplet erecord s wereavailabl ei sdisplayed .I fth ecal fdied ,an dals oi fth e cowwa sno tmilked ,th ecalvin ginterva lwa sextende d significantly.Th esignifican tdifference sfoun dbetwee nth e systemso rth eparitie sar eroughl ycomparabl et othos egive n intabl e3 .Her eals oth ecalvin ginterva li slonges t inGM S1 . Inthi scas ethi svalu ei ssignificantl ydifferen tonl yfro m GMS2 .Th ecalvin ginterva li sals olonges ti nth efirs t parity,significantl ylonge rtha ni nth ethir dan dfourt h parity.

Parto fth eresult so fth emode luse dfo rth eevaluatio n ofth egirt hmeasurement si sgive ni ntabl e5 .Difference s betweenth eGrazin gManagemen tSystem sar esmal li nal lag e groups.I nth eag egrou pbetwee n0 an d1 year ,th eanimal si n GMS3 hav ea significantl ybigge rgirt hsiz etha ni nal lothe r agegroups .I nth eag egrou pbetwee n1 an d2 years ,GM S3 stil l differssignificantl yfro mGM S1 an dGM S4 .I nth eag egrou p over2 years ,th eanimal si nGM S1 appea rt ob esignificantl y smallertha ni nal lothe rsystems .Ther ei sa clea rdifferenc e betweenth esexes .I nth egrou pbetwee n0 an d1 yea rth e femalesar esmalle rtha nth emales .I nth esecon dag egrou pn o significantdifferenc ecoul db esee nbetwee nth emale san dth e females,bu ta distinc tdifferenc eexiste dwit hth eoxen .I n thethir dag egrou pth edifferenc ebetwee nfemale san doxe ni s considerable.I nal lag egroup sseasona linfluence sca nb e identified.I nseaso n1 ,th elat ewe tseason ,th eanimal s appeart ohav eth ebigges tgirth ,whil ei nth esecon dhal fo f theyear ,th eho tdr yseaso nan dth eearl ywe tseason ,th e girthsar esmallest .Whe nth ecombine deffect so fseaso nan d herdmovemen tpractic e (transhumanceo rsedentarism )ar e assessed,i tappears ,tha twithi nth etranshuman to rsedentar y

76 Table 4. Estimated valueso f part of themode l used for the evaluation of calving intervals on the basis of all completed lactationswit h complete records in traditionally managed cattle inth eWester n Province of Zambia.

Calving interval (days)

Variable Number Value s.e.

Overall 719 599 + 7.9

Parity 1 219 632a +10. 2 2 179 602ab +10. 7 3 138 574b +11. 3 4 104 592b +12. 6 >4 79 595ab +14. 5

GMS 1 199 621a +10. 4 2 166 575b +11. 7

3 197 609a +10. 5 4 157 591ab +10. 9

Calfweaned/dea d Weaned 587 566a + 5.1

Dead 132 632b + 14.7

Cowmilke d Yes 354 580a + 10.7

No 365 618b + 9.0

Regressioncoefficien t forc ovariable 0.86647 + 0.03194 Removal agecal f Valueswit hdifferen tsuperscript sdiffe rsignificantl y(p<.005) . GMS=Grazin gManagemen tSyste m

groups similar differences between the seasons canb e seen, with the exception of the sedentary group of over twoyears . Here itwoul d seem that the girth sizes aremor e stable than in the transhumant group.

Discussion.

The percentage of cows over the ageo f twoyear stha thalv e calved inth e respective Grazing Management Systems (GMS) as shown intabl e 2 should be judged with two remarks inmind . The

77 Table 5. Estimated values of part of the model used for the evaluation of girth sizes (in cm.)/ i-n traditionally managed cattle in the Western Province of Zambia. The values in the model are corrected for age.

Agegrou p Agegrou p Agegrou p 0-1 year 1-2 year over2 years

Variable Value s.e. Value s.e. Value s.e.

Numberi n group 1023 627 322

Averageg rth 95.85 122.26 151.34

Averageag e(mths ) 6.35 18.02 59.47

GMS 1(T ) 94.708* +0.4 1 118.85a +0.8 5 148.75a + 1.32 (System) 2(T ) 94.65a +0.5 4 122.99ab + 1.23 154.09ab + 1.73

3 (S) 97.22b +0.5 1 124.06b +0.7 3 154.50b + 1.43

4 (S) 94.49a +0.6 8 121.078 + 1.29 153.66ab +2.5 1

Sex F 94.17s +0.3 5 120.59a +0.6 2 147.66a + 1.09

M 96.35b +0.3 8 120.41a + 1.12 - - 0 - - 124.22b + 0.83 157.84b + 1.29

Season 1 99.36a +0.4 4 126.998 +0.7 1 157.20a + 1.42 2 94.60b +0.6 1 123.95a + 1.05 152.47ab + 1.58

3 91.44c +0.5 6 116.21b ± 1.28 151.22ab +2.5 2 4 95.64b +0.5 3 119.82b +0.9 3 150.11b + 1.40

System* S*1 100.11a +0.6 5 127.89a + 0.92 156.66 + 1.82 Season S*2 95.16b + 0.97 127.14a + 1.59 153.82 + 2.42

S*3 91.14c +0.8 4 115.81b + 1.75 153.35 +3.3 8

S*4 96.99b + 0.87 119.41b + 1.55 152.50 • 2.44

T*1 98.62a +0.5 9 126.088 + 1.05 157.748 +2.0 6 T*2 94.04b +0.6 9 120.ri° + 1.26 151.11ab + 1.91 T*3 91.76b +0.7 2 116.61b + 1.79 149.09ab +2.8 4 T*4 94.29b + 0.60 120.22b +0.9 3 147.73b + 1.49

Values with different superscripts differ significantly (p<.005) GMS = Grazing Management System

T s Transhumance S - Sedentarism

78 resultsma yhav ebee ninfluence db yth eproportio n (between 17.6an d24. 2% dependin go nth eGMS )o fanimal stha tha sbee n inth eherd sfo rles stha na year .Anothe rdisturbin gfacto r is,tha tth eag eo fmos to fth eanimal si nth eearl yphase so f themonitorin gprogramm eha dt ob eestimated .Al lcow sove rth e ageo ftw oyear swer econsidere dt ob eread yfo rconception . Themea nag ea tfirs tcalving ,whic hdi dno tsho wsignifican t differencesbetwee nsystem san di stherefor eno telaborate do n extensively,i saroun d135 0days .Thi svalu ei shighl y variable,an dth eyounges tage sa twhic hcow swer efoun dt o calvewer eindee dno tmuc hhighe rtha ntw oyears .Becaus eo f therelativel y largetransfe rfigure ,th euncertainty ,t osom e extent,abou tth eag eo fth eyounge ranimal sa tth estar to f thesurvey ,an dth ebroa drang eo fage sa tfirs tcalving ,i t wasdecide dno tt ous ecalvin gpercentag ea sindicato ro f reproductiveperformance ,bu tt ous eth eresult so fthi stabl e asindicativ einformatio no nth efertilit yonly .

InGrazin gManagemen tSyste m1 a relativel ylarg e percentage (55.2)o fth eanimal sd ocalve ,especiall yi f comparedwit hGrazin gManagemen tSystem s2 an d4 (46.7an d39. 9 % respectively).Th epercentag etha tcalve donl yonc ei sals o highest (49.4% a soppose dt o30. 2 (GMS 2), 39.5 (GMS3 )an d 23.3 (GMS4)) . InGrazin gManagemen tSyste m4 th epercentag eo f animalstha tcalv ei ssmalles t (39.9),bu tth epercentag etha t hasit sfirs tcalvin gbelo wth eag eo ffou ryear si sb yfa rth e highesti nthi ssyste m (81.2% ,a soppose dt obetwee n66. 5an d 72.7% fo rth eothe r systems),a si sth epercentag eo fanimal s thatcalv emor etha nonc e (76.7,a soppose dt obetwee n50. 6an d 69.8% fo rth eothe rsystems) .Th epercentag eo fanimal stha t calvethre etime swithi nth esurve yperio d islowes ti nGM S1 . Inth eothe rsystem sthi svalu ei sroughl ythre etime sbigger .

Inaccordanc ewit hRevei l (1975)seasonalit y incalving , thoughno tmentione d inth eresults ,wa sfoun di nth esurvey . Roughly 70% o fth ecalving stoo kplac ebetwee nMa yan d November,correspondin gwit hconception sbetwee nSeptembe ran d February.Som edifference sseeme dt ob epresen tbetwee nth e systems;i nGM S1 7 0% too kplac ei nth efiv emont hperio do f Julyt oNovember ,wit ha distinc tpea k (23% o fal lcalvings ) inSeptember ;i nGM S2 7 0% too kplac ei na 7 mont hperio dfro m Mayt oNovember ;i nGM S3 7 0% too kplac ei na si xmont hperio d fromMa yt oOctober ,an di nGM S4 fro mJun et oNovember .I nGM S 2,3 an d4 th ecalving swer emor eo rles sevenl ydistribute d overth emonth si nth eperiod smentioned .I nMal ith esam e relationbetwee nconceptio nperio dan dwe tseaso nwa sfoun d (Wilson,1985) .Th eresult sdisplaye d infigur el asuppor tth e

79 findingso nseasonalit y inconceptions .Aroun d 50% o fth e animalshav ea calvin ginterva lbetwee non eyea ran d2 0months , meaningtha tmos to fthei rdeliverie swoul dtak eplac ewithi n thecalvin gseason .Th eanimal swil lhav et ob ei na noptima l conditionfo rconceptio na tth etim eo fsirin g (Chandler, 1971).Fo raroun d2 0% o fth eanimal sth edependenc yo na favourableseaso nfo rconceptio nseem st ob ever ycritical ;i f theyd ono tattai nth edesire dconditio nwithi nthre emonth s afterth ebirt ho fthei rcalves ,the ywil lno tbecom epregnan t beforeth enex tseason ,exactl yon eyea rlater ,resultin gi n calving intervalso falmos texactl ytw oyears .Fo rth eanimal s thathav ea calvin ginterva lo fles stha ntw oyear sattainin g therequire dconditio ni sapparantl y lesscritical yconnecte d toa perio do fth eyear .Figur el bshows ,tha trelativel yman y ofth eanimal shavin ga calvin g intervalo ftw oyear sar e presenti nGrazin gManagemen tSyste m 1.Th einformatio ni n table2 ,tha ti nGrazin gManagemen tSyste m 1th eproportio no f cowscalvin gonl yonc edurin gth esurve y isbiggest ,als o supportsthes efindings .

Theresult sshow ni ntabl e3 als osuppor tth efinding s relatingt oth ecalvin g intervali nGrazin gManagemen tSyste m 1.I ti ssignificantl ylonge rtha ni nan yo fth eothe rGrazin g ManagementSystems .Wher eGM S1 combine sa lon gmilkin gperio d anda hig hweanin gag ewit ha lon ginterva lbetwee nbirt han d starto fmilking ,a lon ginterva lbetwee nweanin gan dth enex t delivery anda lon gmea nlengt ho fth ecalvin g interval,GM S2 showsth esam elengt ho fth emilkin gperio dan dth esam e weaningage ,whil efarmer sdecid et ostar tmilkin gth eanimal s earlier,th enex tdeliver ycome sconsiderabl y sooneran dth e calving intervali si nth esam erang ea stha to fGM S3 an d4 . Assumingtha tth eamoun to fmil ktake nfro man yco wdoe sno t differver ymuch ,th eaverag eamoun tpe rda ype rco wbein g 0.7 liters (Besselan dDaplyn ,1977) ,an drealisin gtha tbod y conditioni sessentia l forbot hconceptio nan dmil kproductio n capability (Nicholsonan dSayers ,1987 )i twoul dappea rtha t thecow si nGM S2 ar ei nth ebes tpositio nfo roptima l performance,i fcompare dwit hth eothe rsystems .Fertilit yi s influencedb yth enutritio no fanimal s (Nadaraja,1978) .Thi s maysugges ttha tth enutritiona lstres si sleas tsever ei nGM S 2.

Invie wo fth eimportanc eo fbod yconditio nfo rmil k production (Nicholsonan dSayers ,1987 )i tma yb eargued ,tha t thesignifican t influenceso fth eseason ,foun dfo rth e intervalbetwee ncalvin gan dth estar to fth emilkin gperiod , thelengt ho fth emilkin gperio dan dth eag eo fweanin go fth e

80 calf,i sals oexplaine db ydifference si ncondition .I twoul d seemtha tfo ranimal stha tcalv ei nth efirs thal fo fth ewe t season (season 4), ina perio dwhe nregrowt ho fvegetatio ni s atit sfastest ,th enutritiona lstatu sallow smilkin ga ta n earlierstag etha ni nth eothe rseasons ,althoug hth e differencei sonl ysignifican twit hth evalu eo fseaso n2 .Cow s calving inseaso n4 als oappea rt ohav ea relativel ylon g milkingperiod .Her ealso ,th edifferenc ei sonl ysignifican t withseaso n2 .Th emomen tcow sar ebein gmilke d forth efirs t timean dth elengt ho fth eperio danimal sar ebein gmilke dar e decidedupo nb yth efarmers .I twoul dappea rtha tfarmer sus e thenutritiona lconditio no fth eanima la sa nindicatio nt o determinewhen ,an dpossibl y if,t ostar tmilking ;the yar e likelyt opostpon emilkin gwhe nanimal sdelive rdurin go r shortlybefor eth edr yseason ,whe nth enutritiona lstres si s atit shighest .

Themomen tth ecalve swer eweane d seemedt ob einfluence d bypregnanc yo fth ecow .Onc eth eco wi spregnan t foraroun d threemonths ,sh erefuse st ole tth ecal fdrink .I fcow s deliveri nseaso n2 ,th eweanin gag ei s36 5days ,shorte rtha n thevalue so fth eothe rseason san dsignificantl ylowe rtha n thato fanimal stha tcalv ei nseaso n1 .I twoul d suggest,tha t animalstha tcalv eeithe ri nseaso n1 o rseaso n2 ar elikel yt o conceivea ssoo na sth eenvironmenta lcircumstance sar e favourable,earl y inth enex twe tseason .Th eduratio no fth e calving intervalo fcow scalvin gi nseaso n1 i ssimilarl y longertha ntha to fcow scalvin gi nseaso n2 .Thes edifference s arehoweve rno tsignificant .Influence so f6M San dparit y probablycontribut emor et odeterminin gth eduratio no fth e calvinginterval .

Aninfluenc eo fth eparit yca nonl yb eidentifie do nth e calving interval.Bot htabl e3 an dtabl e4 sho wthi seffect . Noneo fth eothe r intervalsmentione d intabl e3 i sinfluence d byparity .Th ecalvin ginterva li slonges tafte rth ebirt ho f thefirs tcalf .Th erelativel yhig hmaturin gag eo fcattl eo n tropicalpasture s (Masonan dMaule ,1960 )i slikel yt ob eth e causeo fthis .Whil eth eanimal sar estil lgrowin g itma yb e moredifficul tt oge tthe mi ncal ftha nwhe nthe yhav efull y matured (Peters,1983) .

Theconclusion so fNicholso nan dSayers ,draw nfo rBora n cattlei nKeny a (1987)tha tbod yconditio ni sa majo rinfluenc e onmil kproduction ,an dthroug htha tals oo ncal fsurvival ,an d onreproductiv eperformance ,coul db eapplie dt oth eresult so f table4 .Thi sanalysi swa saime dmainl ya tidentifyin g

81 influenceso fth ewa yi nwhic hth ecal fwa sremove d fromit s mother,throug hweanin go rdeath ,an do fmilkin go nth ecalvin g interval.Bot hdi dsho wsignifican tdifferences .Th ecalvin g intervalsappea rt ob elonges twhe nth ecow sar eno tmilked , andwhe nth ecalve shav edied .I ti slikel ytha tth econditio n ofth eanimal sals oplay sa rol ehere .A salread ystated , farmersobviousl ydecid ei fanimal sar et ob emilked ,an di t mayb eexpecte dtha tthe yals obas ethei rjudgemen to nth e conditiono fth eanimals .Th efinding sregardin gth einfluenc e ofparit yan do fGM Si scomparabl et othos eo ftabl e3 .

Theinteraction so fseaso nan dGM San do fparit yan dGMS , included inth emodel sfo ranalysi so fvariance ,di dno tsho w additionalinformatio no rclea rsignifican tdifferences . Calving intervalso fBarots ecattl ederive d fromliteratur e rangefro maroun d60 0day s (Reveil,1975 ,Lutke-Entrup ,1971 ) toaroun d88 0day s (Besselan dDaplyn ,1977 ,Perr ye tal. , 1984).

Allothe rGrazin gManagemen tSystem ssee mt ola gbehin di n girth,compare dt oGM S3 (table 5), butthi sdifferenc ei smad e upfo rwhe nth eanimal sgro wolder ,excep t inGM S1 ,wher eth e animalsove rth eag eo f2 year sappea rt ob esmalle rtha ni n allothe rgroup so ftha tage .I tma yseem ,tha tth enutritiona l stress,suggeste dt ob epresen ti nGM S1 b yth ereproductio n resultsalread ydiscussed ,ca nb eidentifie d inth egrowt ha s well.A clea rinfluenc eo fth eseaso nca nals ob eidentified . Thehighes tpressur eo nth edevelopmen to fth eanimal si ssee n inth elat edr yseason ,specificall y inth eanimal su pt oth e ageo f1 year ,whil ei nth ewe tseaso ncompensatio no fth e growthtake splac ean dth econditio no fth eanimal si sa tit s best inth elat ewe tseason .I nth eliteratur ecompensator y growthi nSang acattl ewa sdescribe db ySmit han dHodnet t (1962).Wilso n (1987)describe d seasonaleffect si ncattl ei n Mali;weigh twa sno tonl yrelate dt oth eseason ,bu tals ot o theseaso no fbirth ,whic hinfluenc eseeme dt olas tthroughou t life.Th edifferenc ei ngirt hbetwee nfemal ean dmal ecalve si s notfoun d inth eag egrou po f1 t o2 years .Th ereaso nfo rthi s maybe ,tha tth ebigges tmale si nthi sag egrou par ecastrated , sincei ti spreferabl et ochoos ewel ldevelope danimal sfo r workoxen.I tma yb eth ecase ,tha tth ebod yconformatio nan d sizeals odetermine sth emomen tth eanimal sar ecastrated ; smalleranimal sma yb ecastrate d later,thu scontributin ga s malest oth eanalysi so fthi sag egroup .Th emale swer en o longerinclude d inth eanalysi so fth egrou pove rth eag eo f2 years,sinc ethei rnumbe ri sto osmall .Th erelatio no fth e rangelandconditio nan dth egrowt ho fth eanimal si sals o

82 mentionedb yBloc k (1958),wh odescribe da relativel ygoo d adaptabilityo fth eBarots ebree dt oadvers enutritiona l circumstances,an dCruickshan ke tal . (1976),wh oreporte d considerableresult si nfeedin gtrial swit hBarots esteers .

Theresult sgive nindicat etha tseaso ni sa majo r influenceo nperformance ,bot hi nreproductio nan di nweight . Thenutritiona lstres scause dperiodicall yb yth echange so f seasoni sa facto rtha tca nhardl yb einfluence d intraditiona l lifestocksystem scharacterise db ya ver ylo winpu tlevel . Improvingreproductiv eperformanc ema ybes tb eattaine db y tryingt oinfluenc eth ecalvin gseaso ni nsuc ha way ,tha ta s manycow sa spossibl ear esire di nth efirs thal fo fth ewe t season.Th ecurren tpractic eis ,tha tbull sgraz ewit hth eher d allyea rround ,an dtha ti twoul db erathe rdifficul tt o separatethe mpar to fth eyear .Som eattentio nma yals ohav et o begive nt oth ecow/bul lrati oi fsirin gseason sar et ob e maintained.Influence so fth eGrazin gManagemen tSystem swer e alsoidentified .Th eGrazin gManagemen tSystem sgiv ea n indicationo fth eenvironmen t inwhic hth eherd sar e maintained.Th emanagemen tdecision so fth efarmer sar ehighl y dictatedb yth ecircumstances .A sfa ra snutritiona lstres s resultingfro menvironmenta lcharacteristic s isconcerned , improvementsma ymainl yhav et ob esough ti nthoroug hanalysi s ofth egrazin gpractice san ddecisio nmakin grelatin gt o grazing,aime da tdevelopin gextensio nmessage scontainin g recommendations forpastur eselection .Thes erecommendation s should intha tcas etr yt oai ma timprovin gbod yconditio na s soona spossibl eafte rth estar to fth ewe tseason .Throug h this,i tma yb epossibl et ohav eth ecow si nth ebes tpossibl e condition forconceptio ni nth eearl ywe tseason .Seasonal , nutritional stressi softe naggravate db yindiscriminat e burningo fol dgras si nth edr yseason ,depletin gth estandin g haystock s (Matthewman,1980) .Discouragin gthi spractic ema y atleas tcontribut et osom eexten tt omaintainin gweigh tan d "condition.

Geneticdifference sbetwee nanimal sfro mth erespectiv e GMSi nterm so ffo rexampl ebod yconfirmatio nan dmetabolis m couldtheoreticall yhav eplaye da role ,bu ti ti simpossibl et o evaluatethi seffec twit hth epresen tmaterial .Thi si sals o thecas ewit hinbreeding .Mayb eselectio nfo rshorte rcalvin g intervals,o rrather ,fo rlowe rdependenc yo nfavourabl e conditionsfo rconception ,i spossible .Fo rthi si twoul db e necessarytha ta syste mo findividua lperformanc eevaluatio n wouldb edeveloped ,suc ha swa spropose db yFaugér ean dFaugér e (1986)fo rsmal lruminants .Thi ssyste mwoul dhav et ob e

83 suitable forus e by the individual farmers.Multipl e ownership in herds however (Beerling, 1990) is likely tomak e it more difficult to encourage farmerst o follow recommendations aimed at improving performance of individual animals than to follow recommendations aimed at day-to-day decisions related to the herd as awhole .

Acknowledgements. The authorswis h tothan kth eDirecto r of theDepartmen t of Veterinary and Tsetse Control Services for hispermissio n to submit thispape r forpublication . The help inth e analysis of the data ofMr .B.O .Brouwe r ofth eDepartmen t of Tropical Animal Production of theAgricultura lUniversit y of Wageningen is also greatly acknowledged.

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32. Wilson,R.T .(1985) .Livestoc kproductio n inCentra l Mali:reproductiv easpect s ofsedentar ycows .Anim .Reprod .Sei .9 , 1-9. 33. Wilson,R.T .(1987) .Livestoc kproductio n inCentra l Mali:factor s influencing growth and liveweight inagro-pastora l cattle.Trop .Anim .Hlt hProd .19 ,103 - 114.

(submitted for publication.)

86 2.4. Herdmonitorin gi ntraditiona lcattl ehusbandr yi nth e WesternProvince ,Zambia ,IV :ownershi po fcattl ean dtransfer s ofanimal sbetwee nherds .

E.G.M.va nKlink 1,J.J.F.M .Corten 1,M.M .Mumbuna 2an dG.G.M . van 'tKlooster 1.

Introduction.

Livestockdevelopmen teffort softe nd ono tattai nthei r objectives,becaus eth eextensio nmessage so rintervention s plannedar eno tfollowe db yth etarge tgrou p (Abalue tal. , 1987, Biggs,1980 ,Beerling ,1990) .Th einterest so fth e farmersar ei nman ycase so fa differen tnatur etha nth egoal s setb ydevelopmen tprojects .I ti sessentia lt oidentif yno t onlyth econstraint stha tar eface dan dar efel ta ssuc hb y farmers,bu tals oth efactor stha tdetermin ebot hth e willingnessan dth eabilit yo ffarmer st ofollo w recommendationso rt oaccep tdevelopmen tmeasures .I ti s difficultt odescrib esocio-economi c factorstha tar eo f generalvalu efo rlivestoc kdevelopment ,fo rwhic hreaso n thoroughknowledg eo fth eloca lsituatio ni snecessar ybefor e recommendationsca nb edesigne d (Little,1984 ,Dicki ean d O'Rourke,1984 ,D eRooi jan dWood , 1990).Th eresearc h necessaryt oacquir esuc hknowledg e isb ynatur einter disciplinary (Shanere tal. ,1981 ,Sollo de tal. , 1984). Ownershipo flivestoc kan dit sdistribution ,a swel la s caretaker systemsi nwhic hfarmer sassum eth etas ko flookin g afteranimal sowne db ythir dpartie sar eimportan tsocio economicaspect sinfluencin gdesig no fdevelopmen tpolicie s (Little,1984) .

Inth eWester nProvinc eo fZambia ,cattl ear eo feconomi c importancean dpla ya nimportan trol ei nth esubsistenc e agriculture,b yprovidin gdraugh tpowe r (Kimmagean dWood , 1988),manure ,milk ,mea tan da sourc eo ffinancia lsecurit y (Beerling,1991) . Inth eframewor ko fth eLivestoc kDevelopmen t ProjectWester nProvinc ea se to fstudie swa scarrie dou tt o acquireknowledg eo nsocio-economi c aspectso flivestoc k

department of Veterinary and Tsetse Control Services, Livestock Development Project Western Province,P.O.Bo x910034 ,Mongu ,Zambi a

2Socio-economic Analysis Team, Livestock DevelopmentProjec tWester nProvince ,Mongu ,Zambia .

87 keeping (DeRooi jan dWood ,1990) .A nextensiv eresearc h proposal,outlinin gth esocio-economi cinformatio nrequire da s abas efo rpolic ydesign ,ha sbee ndrafte d (Wood,1986) .A majorstud yconcern sth eway speopl eacquir ean ddispos eo f animals (Beerling,1986) .Baar s (1987)discusse deconomi c aspectso flivestoc kkeeping .Th evariou sreason sfo rwhic h cattlear eimportan tt oth efarmer sar ereflecte dupo nb y Beerling (1991), anda stud yo nth edistributio no fbenefit s wascarrie dou t (Beerlingan dMumbuna ,1988) .Ownershi po f individualanimal si nherds ,relation sbetwee nvariou sowner s ina her dan dmovemen tbetwee nherd sappeare d inth estudie s mentionedher et oinfluenc egreatl yth eway si nwhic hyield s aredistributed .Woo d (1988)discusse dth eimplication so fth e resultsfo rth edesig no flivestoc kdevelopmen tpolicie san d veterinaryservic erestructuring .

Theher dmonitorin gprogramm ecarrie dou tb yth eLivestoc k DevelopmentProjec t (DeRooi jan dWood ,1990 )provide dth e opportunityt oquantif yth eownershi po fanimal si na numbe ro f herdsan dth eimportanc eo fmovement so fanimal sbetwee nherds . Thispape rpresent sth eresult so ftha tquantification .Som e consequenceso fthes efactor sfo rlivestoc kdevelopmen t policiesar ebriefl ydiscussed .

Materialan dmethods .

Thestud yarea ,th eclimat ean dth eherd sinvolve d inth e schedulehav ebee ndescribe db yva nKlin ke tal .(1994a) .

In4 9o fth eherd sinvolve d inth eher dmonitorin g programmeth eownershi po fal lindividua lanimal swer e recorded,i na cross-sectiona l survey,a tth estar to fth e programme.Als oth erelation sbetwee nth eowner so fth eanimal s andth ecaretaker so fth eherd swer erecorded .Th eowne ro fa n individualanima lha sth epowe rt odecid eo nth eultimat e disposalo fa nanimal ,throug hslaughte ro rsal e(Beerling , 1990).A nowne ro fa herd ,o rrathe rher dkeepe ro rcaretaker , onth eothe rhand ,i sno tnecessaril yowne ro fth eanimal si n theherd .Th eher downe rbear sresponsibilit y forth eherd ,bu t iti spossibl etha th edoe sno tposse san yo fth eanimal si n theher d (Beerling 1990).

Inal lherd sinvolved ,al lentrie so fanimal sint oan d removalso fanimal sfro mth eherd soccurrin gwer erecorde d everytw oweek sb yveterinar yassistants ,ove ra perio do ftw o years.Apar t fromth edate so nwhic hremoval sfro man dentrie s intoth eherd stoo kplace ,the ywer erequire dt oindicat eth e

88 reasonfo rwhic hth eanimal swer eremove do rentered .

Onceever ythre emonth sth eDistric tVeterinar yOfficer s ofth edistrict si nwhic hth eherd swer ebase dvisite dth e herdsi norde rt overif yth einformatio nprovide db yth e veterinaryassistants .Durin gthes evisit schec klist swer e used,o nwhic hth esituatio na tth etim eo fth epreviou sthre e monthlyvisi twa sreflected .Thes echec klist swer e automaticallyproduced ,usin ga napplicatio no nth ebasi so f thegenera lpurpos edat amanagemen tprogramm ePanacea 3.

Results.

Intabl e1 th eownershi pdistributio ni n4 9o fth eherd s involved inth estud yi spresented .Th eher dkeeper sgenerall y ownth elarges tnumbe ro fanimals .I non eher dth eher dkeepe r didno tposses san yanimal .Th ewif e (ori nsom einstance s wives)o fth eher dkeepe rowne d2 animal so naverag ei nhe r husbandsherd .Th echildre nan drelative so fth eher dkeepe r owneda naverag eo fabou t6 animals ,whil enon-relative sownin g cattlei nth eher downe d5 animal so naverage .

Maleowner sappea rt ob eb yfa rth elarges tcategory . Neverthelessi ti sclea rtha twome nd oow ncattle ,an d sometimeseve nconsiderabl enumbers .I non eher dal lcattl e weresai dt ob eth epropert yo ftw owomen .

Figure1 A show sth epercentag eo fth etota lnumbe ro f animalsowne db yth evariou stype so fowners .Th ekeeper so f theherd sowne d43. 6% o fth eanimal si nthem ,th ewive so fth e herdkeeper s3. 1% an dth echildre n13. 2% .I nmos tcase sth e herdsconsiste dpredominantl yo fanimal sowne db yth edirec t family.A tota lo f91. 7% o fth eanimal si sowne db yth eher d keeperso rthei rfamil yan drelatives .Th eres to fth eanimal s isowne db ynon-relatives ,wh ohav eentruste dthei ranimal st o thecar eo fth eher dkeepers .

Figure1 B represent sth enumbe ro fherd swit hvariou s numberso fowners .Th enumbe ro fowner si na her dca nvar y greatly.Th enumbe ri srarel yver ylarge .I n3 8herd sth e numbero fowner si sles stha n10 ,i n2 9herd sles stha n6 .I n figure1 C th enumbe ro fowner si na her d isrelate dwit hth e herd size.Thi srelatio nprove dt ob esignifican t (p<.005).

3(c)Pa nLivestoc kService sLtd. ,Reading ,UK . 89 Table 1. The ownership distribution of 3196 head of cattle in 49 herds inthe Western Province of Zambia.

Type of owner Total Mean Range number of numbero f animals animals owned owned A.Herdkeepe r 1394 28.4 0-94 B.Wif eo fA . 100 2.0 0-17 number C.Childre n 72 423 5.9 0-29 ofA . D.Relative s 176 1014 5.8 0-18 ofA . E.Other s 53 265 5.0 0-23

I. Male 224 2470 11.0 0-94 owners II.Femal e 111 639 5.8 0-30 owners III.Sex owner 30 87 2.9 0-14 unknown

Intabl e 2the total number of changes inthe herds that occurred over atw o year period isrepresented . A distinction was made between "true" entries and removals,meanin g that animals were not present inthe cattle population of Western Province before, or were totally removed from the cattle population of the Western Province, and transfers between herds within the cattlepopulatio n of theprovince .Al l "true" entries are animals that were born inthe herds, and all "true" removals are animals that died or were destined to be slaughtered, either through local slaughter, usually in emergency, or through being sold for slaughter. Around two thirds of all changes belong to either "true"entrie s or "true" removals.

The rest of the changes aretransfer s between herds within the system. Of the entries, 28.8 % inthi s group are purchases,

90 Figure1 . Ownershipi n4 9herd sfro mth eWester nProvinc eo f Zambia.

A.Proportio no fth eher downe db yvariou stype so f owners. A.

Relationships of owners Sexo fowner s

B.Numbe ro fherd swit hvariou snumber so fowners .

C.Relatio nbetwee nher dsiz ean dth enumbe ro f owners. C.

at» Ï t •

i c> • 10 1« 20 NM* of M«I »

91 Table2 . Distributiono freason so f167 7entrie san d136 4 removalso fanimal sfro mherd si nth eWester n Provinceo fZambia ,recorde dbetwee n1/4/8 6an d 1/4/88.

Entries(A . » Trueentrie s (A1.) Transfers intoherd s (A2.) Reason %o fA . Reason Xo fA2 . %o fA . Born 63.3 Bought 28.8 10.6 Herding 23.6 8.7 Reclaimed 19.8 7.3 Exchanged 11.5 4.3 Brideprice 8.7 3.2 Inheritance 2.7 0.9 Hireo rloa n 2.4 0.9 Gifts 1.5 0.5 Payments 0.7 0.3 Not specified 0.3 0.1 TotalA1 . 63.3 TotalA2 . 36.7

Removals(B ) True removals(B1 ) Transfersou to fherd s (B2) %o fB1 . %o fB . %o fB2 . %o fB . Died 53.0 35.1 Reclaimed 44.8 15.1 Soldfo r 33.1 22.1 Herding 19.3 6.5 slaughter Brideprice 12.2 4.1 Slaughtered 13.7 9.1 Exchanged 11.1 3.8 Inheritance 3.5 1.2 Sold 3.3 1.1 Payments 1.9 0.7 Lost 1.7 0.6 Gifts 0.6 0.3 Not specified 1.6 0.5 TotalB1 . 66.3 TotalB2 . 33.7

92 andanothe r 19.8% consist so fth eanimal stha twer ereclaime d fromelsewhere ;animals ,owne db yth eher dkeepe ro rhi s family,tha twer ekep ti nanothe rher dunde ra herdin g arrangement.Exchange so fanimal sfo rothe ritem so ranimals , andanimal sreceive da sbridepric eaccoun tfo r11. 5an d8. 7% ofth etransferre dentrie srespectively .Th eothe rreason sfo r whichanimal sente rth eher dar enumericall y lessimportant .

Byfa rth elarges tpar to fth eremoval si nthi sgrou par e theanimal stha tar etake nbac kb ythei rorigina lowners ,i.e . animalstha thav ebee nkep ti nth eherd sfo rother s (44.8 %). Removalsbecaus eo fexchange s (11.1 %), bridepricepayment s (12.2% )an danimal stake nou tt ob ekep ti nothe rherd s (herdingarrangements ) (19.3% )als oaccoun tfo ra considerabl e proportion (table 2).

Discussion.

Ownershipprove dt ob ea complicate dconcep t (Beerling 1986, 1991).Thi si scause db yth efac ttha ti nth eLoz i languageth ewor d "owner"ha sa broade rmeanin gtha nlega l ownershiponly .Onl yafte rresearc hint oth esocia lstructur e andcontex to fownershi pwa sstarte d (Beerling 1986),th e conceptcoul db eoperationalized .Onl ywhe nth efirs t qualitativeanalyse so fth eownershi pconcep twer ecarrie dout , quantitativeapproache sa spresente dhere ,an dstudie sint o benefitsan dth eeconomi cpositio no fcattl ei nsociet ycoul d bestarte d (Baars,1987 ,Beerlin gan dMumbuna ,1988 ,Beerling , 1991).

Inpracticall yal lcase sanimal sfro msevera lowner sar e present inth eherd si nWester nProvinc e (Beerling,1990) .Th e majorityo fth eanimal si nth eherd sar eowne db yth eher d owner,hi sfamil yan drelative s (table1 an dfigur e1A) .Th e numbero fanimal sowne db y"outsiders "i ssmall .Normall yth e herdownerwil lposses sth elarges tnumbe ra swel la sproportio n ofanimals .Th enumbe ran dproportio no fanimal sowne db yth e wiveso fherdowner si ssmall .Wome nofte nleav eth eanimal s theyow ni nth eherd so fthei rfathers ,rathe rtha n transferringthe mt oth eher do fthei rhusband s (Beerling, 1986).Wive sar eno tconsidere dmembe ro fth efamil y inth e Lozikinshi psystem .This ,an dth efac ttha tdivorce soccu r relatively frequently,i sth ereaso nfo rwome nt oleav ethei r animalsi nth eherd so fthei rfather so rothe rmal erelatives .

Beerling (1991)presente da nanalysi so fownershi po nth e basiso finformatio nfro mherd si ntw oo fth edistrict si nth e

93 province.Th eproportion so fanimal sowne db yth evariou sowne r categoriesdiffer ,bu tgenera lconclusion stha tca nb edraw n aremostl ycomparabl ewit hthos eo fth epresen tstudy .Th eher d keeperowne so naverag eth elarges tproportio no fth eanimals , ando fth eres to fth eanimal sth emajorit ybelong st oth e childrenan drelative so fth eher dkeeper .

Beerling (1991)stated ,that ,accordin gt opersisten t rumours,larg enumber so fanimal sar ei nfac towne db yLozi , residingi nth ecapita lan dothe rimportan ttowns ,fa rawa y fromth eWester nProvince .Thi ssituatio nwoul dhampe r livestockdevelopmen tefforts ,sinc ethes ecattl eowner swoul d considercattl epurel ya sprivat einvestment .Furthermore , absenteeownership ,a si ti stermed ,interfere swit hdecisio n makingprocesses .Beerlin g (1991)coul dhoweve rno tfin d evidencefo rthi srumour .Absente eownershi pdoe soccur ,bu t theproportio no fanimal sowne db yabsente eowner si sno t disproportionalt oth eshare so fothe rcattl eowner si nth e herds.

Thenumbe ro fanimal sowne db yan yo fth erespectiv e groupsi sgreatl yvariable .Childre nan drelative sow nalmos t sixanimal spe rperson ,an d1 3an d3 2% o fth etota lnumbe ro f animalsrespectively .Othe rowner sposses sfiv eanimal so n averagean d8 % o fal lanimals .Herdowner sar eresponsibl efo r theday-to-da ymanagemen to fth eherds ,bu tsinc eindividua l animalsar eowne db ya numbe ro fothe rpeople ,decisio nmakin g onth efat eo findividua lanimal si squit ecomplicated .Th e actualowne ro fa nanima lwoul dfo rinstanc eno tdecid eo n selling itwithou tconsultin gth eher downer ,whil eth eher d ownerwoul dno tdecid eo nhi sow no nth epurchas eo fdrug sfo r specificanimals .

Maleowner sposses salmos ttwic ea sman yanimal spe r persona sfemal eowners ,whil emal eowner sposse salmos t8 0% ofal lanimals .Th enumbe ro ffemal eowner si sconsiderabl y smaller.Apparentl ywome nca nan dd oow ncattle ,bu ti tseem s tob eles sself-eviden ttha nwit hmen .Benefit sderive dfro m cattlear elikel yt oreac hwome ni nman ycase sonl yi nindirec t ways (Beerling,1991) .Fo rexample ,revenu efro mth esal eo f milko rth ehirin go foxe nowne db ythem ,doe sno treac hthe m directly,o rma yno teve nreac hthe ma tall .Th ecaus efo rthi s is,tha tthei ranimal sar enormall y leftunde rth ecar eo fa malerelative ,an dtha twome nar erarely ,i fever ,involve di n theday-to-da ymanagemen to fth eherds .Contrar yt owha t Waters-Bayeran dBaye r (1984)foun dfo rth esettle dFulan io f Abeti nNigeria ,wome nar eals ono tinvolve d inactivitie ssuc h

94 asmilking .Mubond a (1993)recommend stha teffort sshoul db e madet oincreas eth einvolvemen to fwome ni ncattl ekeepin gan d themeasur et owhic hthe ybenefi tfro mcattle .Thi si so f particular importance invie wo fth efac ttha tcattl ear e consideredth emain ,i fno tth eonly ,importan tsourc eo f income (Mwafulirwaan dMoll ,1991 )an dtherefor eo frelativ e independencean ddevelopmen to fpersona lprosperity .

FigureI Bshow stha tth enumbe ro fcattl eowner spe rher d mayvar ygreatly .I non eher dth eowne rindicate dtha th edi d notposses san yo fth eanimals ,whil etw oothe rher downer s claimedt oow nal lanimal si nth eherd .I ti spossibl etha t thisstatemen twa smade ,becaus ethes efarmer sconsidere d questionsabou tth eownershi po fthei ranimal srathe rprying . Theexperienc eo fth eenumerato r indealin gwit hsuc h sentimentsma ytherefor ehav ebee no finfluence .

Aregressio nanalysi scarrie dou to nth erelatio nbetwee n thesiz eo fth eherd san dth enumbe ro fowner s (figure1C ) shows,tha tth etota lnumbe ro fowner so fthes ethre egroup s increasessignificantl ywit hth eincreas eo fth eher dsiz e (p<.005).Th enumbe ro fchildre nownin gcattl eha sth ebigges t influence,thoug hno ta tth esam econfidenc eleve l (p<.05).Th e numbero frelative so rothe rowner si sles simportan t inthi s relation.Th esiz eo fth eher dan dth enumbe ro fowner s involvedar elikel yt ob eo fgrea tinfluenc eo nth ecomplexit y ofdecisio nmaking .

No "true"entrie sothe rtha nbirth swer erecorde d inth e herds.Rarely ,i fever ,doe simportatio no fcattl ei n considerablenumber sfro moutsid eth eprovinc etak eplace .Th e cattlekeepin gsyste mo fth eWester nProvinc eca nb econsidere d asa close dsyste m (DeRooi jan dWood ,1990) .Onl yon ethir do f the "true"removal sar eanimal stha tar esol dfo rslaughter . Theothe rtw othird sar eslaughtere d locally,usuall yi n emergency (VanKlin ke tal. , 1994b),o rdie di nth eherds .Thi s isa nenormou slos si neconomi csense .Althoug hth emea to f animalstha tdie di softe neate nan dth eanimal stha twer e slaughtered inemergenc yar eals oconsume do rsold ,th erevenu e thisgenerate si sfa rbelo wtha tearne db ysellin g itfo r slaughteroutsid eth eprovinc e (Beerling,1986) .

Onethir do fal lentrie sint oan dremoval sfro mth eherd s concernanimal stha tar etransferre d fromon eher dt oanothe r fora numbe ro freason s (table2) .Transfer si nth eframewor k ofherdin garrangement sar eb yfa rth elarges tgroup .Owner so f animalsno tnecessarill ytak eu pth ecar eo f (allof )thei r

95 animalsthemselves .Ofte nthe ydecid et oplac eanimal si nth e careo fothe rher downers .Wome nhardl yeve rtak ecar eo fthei r ownanimals ;the ywil lnormall yplac ethe mi nth eherd so f their fathero rbrother s (Beerling,1986) .

Severaltype so fherdin garrangement sexist .The yca nb e distinguishedb yth erelatio nbetwee nth eowne ro fth eanima l andth ecaretaker ,whic hma yb ea famil ymember ,o ra non - familyrelatio no rfriend .Als oth echaracte ro fth eagreement ; whethero rno ta nawar d isgranted ,an dwha tth erewar dshoul d be,determine sth etyp eo fth eherdin garrangement .Th e durationo fth earrangemen t isals oa distinguishin gfactor . Forfamil yfo rinstance ,herdin gma yb edon efo rconsiderabl e periodswithou ta nawar dbein ggranted .Fo rnon-famil y relationsth eduratio nma yb evariabl ean dnormall yon eo rmor e animals,ofte noffsprin go fth eanima ltha ti sgive nint oth e careo fth eher dmanager ,wil lb egive na srewar d (Beerling, 1986).

Changesi nth eherd srelate dt oherdin garrangement s includeanimal senterin gth eher dfo rherding ,o rbein g reclaimed fromothe rherds ,an danimal sremove d fromth eher d becauseo fherdin go rbecaus eo fbein greclaime db yth e originalowner .Aroun d 40t o6 0percen to fal ltransfer s betweenherd sar erelate dt oherdin garrangements .I tma yb e thatpar to fth eanimal stha twer ereportedl yentere d intoth e herdbecaus ethe ywer ebought ,wer ei nfac tanimal stha twer e reclaimed fromothe rherd san dwer eplace db yowner sothe rtha n theher downe runde rhi scare .Th eentr yreaso nwa snormall y givenb yth eher downer ,an dth eowne ro fth eindividua lanima l appearedno tt ohav ebee nasked .I twoul dprobabl yexplai ni n partth ediscrepanc ybetwee nth eproportio no fanimal sbough t andth eproportio no fanimal ssold ,an dbetwee nth eproportio n enteringth eher dbecaus eo fbein greclaime dan dth eproportio n beingremove d forth esam ereason .I twoul dprobabl y showtha t thepercentag eo fanimal senterin gth eher dbecaus eo fbein g reclaimedwoul dprov et ob ei nth esam erang e (around4 5% )a s theproportio n leavingth eher dfo rthi sreason .Similarl yth e percentagebough tprobabl ywoul db ei nth esam erang e (around3 %)a sth epercentag esold .

Bridepricepayment sar estil la nimportan treaso nfo r transfero fanimal sbetwee nherds .Roughl yth esam enumbe ran d proportiono fanimal shav eentere dan dwer eremove d fromth e herdsfo rthi sreason .Th ebridepric ei snormall ypai dt oth e parentso fth ebride .I nmos tcase sth eanimal swil lremai ni n theher do fth efathe ro fth ebride ,althoug hon eanima lseeme d

96 tohav ebee nremove d fromth eher dmos tlikel ybecaus eth e mothero fth ebrid etransferre dhe rshar eo fth ebridepric et o theher do fhe row nfather .

Theimportanc eo ftransfer swithi nth elivestoc kindustr y ofWester nProvinc eha sbee nclearl yillustrate d inthi sstudy . About25 0- 30 0animal schang eherd spe ryea ri nthi sgrou po f herds.O nth etota lnumbe ro fanimal so f250 0t o300 0thi si sa frequencyo f8 - 1 2% .

Asi nman yAfrica ntraditiona l livestocksystems ,i nth e WesternProvince ,animal sar eindividuall yowned ,whil eherd s areofte ncompose do fanimal so fdifferen towners ,unde rth e responsibilityo fa caretake r (Beerling,1986) . Iti slikel y thatth ecaretake rdecide so nth eday-to-da yaffair si nth e herd,suc ha swher et ograze ,whe nt oreleas eth eanimal sfro m thekraal ,whethe rt omil ka nanima lan da twhic hmomen to fth e dayth eanimal sar et ob emilked .Decision so nindividua l animals,no tbein ghi sproperty ,ar elikel yt ob emor e complicated;thi sma y includedisposal ,transfer ,slaughter , butals oapplicatio no fveterinar ytreatment so rvaccinations . Invie wo fth emai nobjectiv eo fth eLivestoc kDevelopmen t Project,improvemen to fth eveterinar y service infrastructure andcost-recover y (DeRooi jan dWood ,1990) , furtherresearc h intoth edecisio nmakin gproces si nth eframewor ko fth e complexownershi prelation si snecessary .

Transfersbetwee nherd sar eo fgrea timportance ,bot h numericallya si nsocio-economi csenc e (Beerling,1986) .Th e relativelyhig htransfe rrat ema yagai ncomplicat eth edecisio n makingprocess .I tcoul deve nb eargued ,that ,especiall yi f greatdistance sar ecovere dwhil etransferring ,the yma ypos e veterinaryrisks .Sprea do fcertai nclostridia l infections (e.g. blackleg)o rhaemorrhagi cseptichaemi ama yb einfluenced , alsobecaus eth etransport ,usuall yo nhoof ,fro mon eher dt o another,ma ycaus estres sleadin gt odepressio no fimmunity .O n theothe rhand ,reason sfo rcattl eowner st oplac eanimal s underth ecar eo fother sma yinclud espreadin gth eris ko f loosingth ecomplet eher di ncas eo fsever eoutbreak so f disease (Beerling,1986) .Othe rreason sma yb elettin gth e animalsbenefi tfro mgoo dpasture si ndesire darea sawa yfro m home,o rhavin gthe msire db yunrelate dbull si norde rt o preventinbreeding .Whil ei ti sgenerall yaccepted ,tha tth e morefrequen tchange si nher dcompositio ntak eplace ,th emor e productivity andhealt hma yb eimpaired ,bot hb ydisruption so f thesocia lorde ri nth eher dan db yth epresenc eo fhealt h hazards,soun dmanagemen treason softe npla ya rol ei nbringin g

97 one'sanimal sunde rth ecar eo fothers .

Itma yb etha tlong-ter mherdin garrangement san dth e movementsthes einvolv ear eaffectin gproductivit y lesstha n situationswher eanimal ssta yi nth eherd sfo rshor tperiod s only.Especiall ythos eanimal sma ypos ehealt hhazard so r spreaddiseas eagents ,mainl ybecaus eo fth etranspor tstres s mentionedearlier .I tremain showeve rdifficul tt odemonstrate , letalon equantify ,th eeffect so frelativel yfrequen t movementso fanimal sbetwee nherd so nproductivity ,includin g reproductiveperformance ,an dher dhealt hi nth erura lsettin g ofth etraditiona l livestockkeepin gsystem si nAfrica .A s Beerling (1986)als omentioned ,herdkeeper so flarge ,thrivin g herdsma yofte nreceiv emor eanimal si nherdin garrangement s thanles ssuccesful lher downers ,resultin gi neve rlarge r herdswit heve rmor eanima ltranfer stakin gplace .

Acknowledgements. Theauthor swis ht othan kth eDirecto ro fth eDepartmen to f Veterinaryan dTsets eContro lService so fth eRepubli co f Zambiafo rhi spermissio nt opublis hthi spaper .Dr .A.P .Woo d and Ir.M.L.E.J .Beerlin gar egreatl yacknowledge d forthei r contributionst oth emanuscript .

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(submitted for publication.)

99 CHAPTER3

Internalparasit einfection san dproductivity .

101 3.1. Introduction.

Diseasesar econsidere dt ob ea majo rconstrain tt oanima l production inth etropic s (Ristican dMclntyre , 1981).Variou s transmissiblean dinfectiou sdisease sar ewidesprea d inth e tropics.Risti can dMclntyr e (1981)specificall ymentio n diseasescause db yhelmint hparasites .Importan ta sthe yare , theinfluenc eo fhelmint hparasite si softe nno trecognised , becausethei reffect sar emaske db ythos eo fmalnutritio n (Troncy,1989) .Acut eclinica ldiseas ea sa resul to f infectionswit hhelmint hparasite si srelativel yrare . Especially inyoun ganimal sinfection swit hparticula rtype so f intestinalworm s (e.g.haemonchosis ,strongyloidosis )d o sometimescaus eseriou sdiseas esymptom si fth eparasite sar e present inrelativel ylarg enumbers .Bu tothe rtype s (fasciolosis,th estrongyloses )generall ycaus ea chroni c subclinicalwastin gdisease ,whic hi softe nmaske db y nutritional factors (Armour,1981 ,Hop eCawdr ye tal. , 1977). Apartfro mwasting ,anaemi a (Kaufmannan dPfister ,1990 )o r hypoalbuminaemia (Rosse tal. ,1970 )i softe nfound .I n liverfluke infectionsth ebigges tdamag ei sdon eb ymigratin g youngflukes ,throug hdirec tdamag et olive rtissu e(Owen , 1984).

Ifno tcausin gacut eclinica ldisease ,th echroni c conditionsbrough tabou tb yparasit einfection saffec tth e healthstatu so fth eanimal si nth elonge rter man ddepres sth e productivityo fth eanimal s (Holmes,1986) .Mil kproductio nma y beaffecte d (Blackan dFroyd ,1972 ,D eRon de tal. , 1990),an d growthreduce d (Chicke tal. ,1980 ,Hop eCawdr ye tal. ,1977 , Abdalla,1989 ,Paren te tSamb ,1984) .Fertilit yma yals ob e adversely influenced (Oakleye tal. , 1979),resultin gi nlowe r conceptionrate san dlowe rcal fweight sa tbirth .Th e patholigicalchanges ,cause db yth epresenc eo fth eparasite s inth eintestine san dth eliver ,tha tar eresponsibl efo rthis , mayvary ,dependin go nth eparasit eo rparasite sinvolve d (Soulsby, 1968). Inliverfluk einfection sanaemia , hypoalbuminaemiaan djaundic ear ecause db yth edestructio no f livertissue,an dthroug hlos so fbloo dfro mth evessels .I n infectionswit hintestina lnematode smalabsorbtio nca nresul t frominflammator yreaction si nth eintestines .Haemonchu ssop . causeanaemia ,a sa resul to fblood-letting .

InAfrica ,th eliverfluk eFasciol agiaantic ai scommo n (Schillhornva nVeen ,1980b) . Themos tcommo nintermediat ehos t ofFasciol aqiqantic ai sLvmne anatalensi s (Schillhornva n Veen, 1980a). Inareas ,wher eth eclimat ei smoderat e (e.g.th e

103 Ethiopeanhighlands )Fasciol ahepatic ai scommo n (Lemmae tal. , 1985).

Ina numbe ro farea si nAfric ainventorie shav ebee n carriedou to fth evariet yo fspecie so fintestina lnematode s incattl ean dsmal lruminants .I neaster nZaire ,a tota lo f2 1 specieso fintestina lnematode swer efoun d (Chartier, 1990). Connore tal . (1990)foun dHaemonchu scontortu sa sth emos t predominantnematod ei ngoat si nTanzania ,whil e Oesophaoostomumcolumbianu man dStronavloide sspecie swer eals o found.Kaufman nan dPfiste r (1990)foun dHaemonchu scontortu s andCooperi aspecie s (C.punctat aan dC .pectinata )a sth emos t abundantspecies ,an dBunostomu mphlebotomu man d Oesophaaostomumradiatu mwer eals oo fimportance .Inventorie s carriedou ti nZimbabw e (Eyskere tal. ,1990 ,Pandey ,1990 ) showed,tha ti ncattl eCooperi aspecie swer eth emos tabundan t strongylidtype sfound ,followe db yHaemonchu splace ian d Bunostomumphlebotomum .I nTransvaal ,Sout hAfrica ,Mala ne t al. (1982)identifie dCooperi aspecies ,Haemonchu splace ian d Oesophaaostomum radiatuma sth emos timportan tnematode s present incattle .

Inth eWester nProvinc eo fZambi asom eresearc hha sbee n carriedou tint oth eprevalenc eo fliverfluk e (Fasciola ctiaantica)infecte d liversan dliverfluk eeg gsheddin g (Jorgensenan dKamukwai ,1977 ,Silangwa ,1972 ,1973 )an d intestinalparasit eeg gsheddin g (Bongers,1987 ,unpublishe d data).

Inorde rt orelat eenvironmenta l factorsi nth eprovinc e toth epatter no finfection swit hliverfluke san dintestina l helminths,a novervie wi sgive no fliteratur eo nresearc hi n thisfiel di nothe rarea si nAfrica .Th egoa lwa st oasses sth e significanceo ffactor sdiscusse d inthi sliteratur e forth e situationo fth eWester nProvince .Als oa novervie wo nth e effectso finfection so ro ftreatment so nproductivit yi s given.Th eai mo fthi sovervie wi st oprovid ebackgroun dfo r thedesig no fa serie so ffiel dstudie sint oth eeffec to f antiparasitictreatmen to nproductivit yan dfo rth esubsequen t discussiono nappropriat econtro lstrategies .

3.2. Epidemiologicbackgroun do fliverfluk einfection si n Africa.

Inth eepidemiolog yo fliverfluk einfection sth efollowin g threemai nphase shav et ob edistinguished :

104 - theintermediat ehost ,th esiz eo fit spopulation ,th e exposureo fth evertebrat ehos tt oi tan dth eperio do f theyea ro rseaso ntha tinfectio noccurs , thepresenc eo fth eliverfluke si nth evertebrat ehost , theseverit yo fth einfection ,it seffects ,an dth ewa y thehos trespond st oit , - thepresenc eo fa paten tinfection ,i.e .a ninfectio ni n whicheg gsheddin gi sfound .

3.2.1. Theintermediat ehos tan dexposur eo fth evertebrat e host.

Schillhornva nVee n (1980a,1980b )describe sth erelatio n betweenth epopulatio ndynamic so fth eintermediat ehos tLvmne a natalensisan dth epresenc eo fFasciol agiqantic a infectionsi n cattlei nZaria ,i nNigeria .Th esnai lpopulatio nbuild su pi n thecours eo fth erain yseason ,an ddecline swit hth ereductio n ofth esiz eo fpool swhe nth edr yseaso nha sstarted .Mos t infectionswit hFasciol agiqantic awer ereporte d fromth een d ofth erain yseaso ntil lth emiddl eo fth edr yseason .B yth e endo fth edr yseaso nacut efasciolosi scoul db eseen .Babalol a andSchillhor nva nVee n (1976)describe da nabbatoi rsurve yi n Bauchii nNigeria ,wher ea naverag eo f31. 7% o fth eliver swa s foundwit ha ninfection .Peak swer efoun di nMarch/Apri lan di n September/October,markin gth estar tan dth een do fth erain y season.I nth eperio dbefor eth erain yseaso nacut eclinica l fasciolosisi ncattl ewa sfound .Probabl yth epoo rnutritiona l statuso fth eanimal swa so fimportanc ei nth eoccurrenc eo f acuteclinica lcase so ffasciolosis .Babalol aan dSchillhor n vanVee n (1976)quote dGrabe r (1971),statin gtha tth e nutritionalstatu so fth eanimal softe ndetermine sth eseverit y ofth edisease .Th eanaemi aan dhypoalbuminaemi acause db y flukeinfection sar ecompensate dmor eeasily ,i fth e nutritional statusi shigh ,tha ni fth eanimal ssuffe rfoo d shortages.I ti slikely ,tha tresistanc eagains tparasite san d parasitic infectionsi sdepresse d intime so fsub-optima l provisiono ffodder .Th ehig hprevalenc ea tslaughte ro f infectedliver si nth eperio d justafte rth erain yseaso ni s morea nexpressio no fth ecullin gpolic yo fth eowners ,wh o probablycul lanimal si nba dconditio nbefor eth estar to fth e dryseason .The yconclude dtha tth einfectio ni susuall y acquired inth esecon dhal fo fth edr yseason ,whe nth ecattl e grazeth efloodplain so fth eNige ran dothe rrivers .Schillhor n vanVee ne tal . (1980)reporte do nresult so fsurvey so f slaughterslab si nth esam eregion .Slaughte rslab sar esmal l scaleloca lslaughterin g facilities,usuall yliterall yonl y consistingo fa concret eslab ,sometime sequipe dwit ha lo w

105 wall,an dver yrarel ywit ha bea man dtackle .The yindicate d that65. 4% o fth ecattl ewa sfoun dinfected ,wit hpeak sa tth e starto fth edr yseason .Thes epeak sma yals ohav ebee nth e resulto fincrease dcullin go fanimal si ndepresse dcondition . Iti sremarkable ,tha ti nth esurve yo nslaughte rslab speak s atth estar to fth edr yseaso nwer efound ,whil ei nth e abbatoirbot ha tth een dan da tth estar to fth ewe tseaso n peakswer efound .Th ecaus efo rthi sma ybe ,tha tth eanimal s thatar eslaughtere da tth eloca lslab sar egenerall yanimal s ofwhic hth egenera lconditio ni sver ypoor ,a sa resul to f whichthe yar eno tadmitte d forslaughte ra tabbatoirs . Although,a sstate db yBabalol aan dSchillhor nva nVee n (1976) cullingma yhav einfluence dth eprevalenc erat eo finfecte d liversi nth eabbatoi rsurvey ,i ti sprobable ,tha tth eanimal s slaughtered atloca lslaughte rslab sar ea neve nmor eselecte d group.

Tembelye tal . (1988)discusse dth eprevalenc eo f liverflukei nMal io nth ebasi so fslaughterhous esurveys . Particularly inth eSahelia nzon eo fMali ,i nwhic hcattl e grazeperiodicall yo nth efloodplain san dinlan ddelta so fth e Nigeran dSenega lrivers ,th eleve lo finfectio nwit hFasciol a giqanticai shigh .Th epercentag eliver sfoun dwit ha n infectioni nthi szon ewa s5 0% .I nth econsiderabl ydrie r subdesertic zoneth eprevalenc ewa slow ,les stha n1 0% .I nth e Sudanesezon eth eprevalenc ewa sslightl yabov e1 0% .I nthi s publicationth erelatio nbetwee nclimati czone ,an dwit htha t thehusbandr ypractic erelate dt othi szone ,an dinfection si s emphasized.Especiall yexposur eo fth eanimal sdurin gth e periodstha tthe yar egrazin gth efloodplain swa sreporte dt o playa part .

Scottan dGol l (1977)showe da relatio nbetwee nFasciol a hepatica infectionsi ntrace rlamb si nth eEthiopia nHighland s andth erai nperiods .Mos tinfection soccurre dbetwee nAugus t andJanuary ,wit hpeak si nth enumbe ro ffluke sfoun da t postmortemexaminatio n inOctober/November .Th erainfal l inth e areawa sconcentrate dbetwee nMa yan dSeptember ,wit hth e highestamoun to frai ni nJuly .Th epatter no finfection s closely followedth erainfal lpatter nwit ha tim ela go f approximatelythre emonths .Durin gth erainfal lperiod sth e conditionsfo rexposur eo fth eintermediat ehos tt omiracidi a areoptimal .Afte ra developmen tphas ei nth esnail , metacercariaear ereleased .Aroun dthre emonth safte rth ewe t seasonth einfection sbecom edetectabl ei nth evertebrat ehost , becauseth edevelopmen t frommiracidiu mt ometacercari ai s completed inth esnail ,th e (infected)snail sconcentrat ei n

106 smallerpool si nth ecours eo fth edr yseason ,an dth e vertebratehost sals odra wneare rt othes epools ,becaus eth e qualityo fth egrazin gremain sreasonabl enea rwater ,an d becausethe yrequir eth ewate rfo rdrinking .

3.2.2. Effectso fliverfluk einfection si nth evertebrat e host.

Infectiono fth evertebrat ehos twit hmassiv enumber so f juvenilefluke sma ycaus eacut efasciolosis ,a sa resul to f directdamag eo flive rtissu edurin gth emigratio no fth e flukes (Schillhornva nVeen ,1980b ,Soulsby ,1968) .Thi s conditioni softe nsee ni ninfecte dsmal lruminants ,an d relativelyrar ei ncattle .A subacut esyndrome ,cause db yyoun g adultfluke sfro mth emomen tthe yente rth ebil educt si smuc h morecommo ni ncattl e (Schillhornva nVeen ,1980b) . Inthi s syndromeanaemi ai sfound ,an dth econditio no fth eanimal si s slowlydeclining .I tmay ,i narea swher ebot hdisease sar e found,a ttime sb econfuse dwit htrypanosomosis .A chroni cfor m iscause db yadul tflukes ,residen ti nth ebil educts .Smal l numberso f flukesca ncaus ea chroni cwastin gdisease .

Theinfectio nwit hjuvenil efluke scause sfibrosi so fth e liver.Onc eth efluke sente rth ebil educts ,calcificatio nan d thickeningo fth ebil educ twall sstarts ,a sKendal lan d Parfitt (1975)describe d forFasciol ahepatica .Simila rchange s arefoun d inliver sinfecte dwit hFasciol agigantica .Thes e processes,togethe rwit hth edevelopmen to fimmunity , contributet oth eresistanc eo fth evertebrat ehos tagains tne w infections.Partl ya sa resul to fthes echange si nth elive r tissue,th ehos tals oappear st ob eable ,t osom eextent ,t o rejectth eparasite s (Kendallan dParfitt ,1975) .Becaus eo f this,th epercentag eliver sfoun dwit ha liverfluk einfectio n inan yperio dca nb econsidere dt oreflec tsom eo fth eseasona l influence.Hughe s (1985)found ,tha trejectio no ffluke swa s causedb ya nincreasin ginabilit yo fth efluke st ofee da sa consequenceo fth epathologica lchanges .I tmus tb eborn ei n mind,tha tth einfection sar ealway sabbatoi rfindings .Th e presenceo fa ninfectio naffectin g its'conditio nma yinfluenc e thedecisio nt oslaughte ra particula ranimal .

3.2.3. Eggshedding .

Babalolaan dSchillhor nva nVee n (1976)foun dtha t liverflukeinfection sbecam epaten ti nth elas tmont hbefore , andi nth efirs tmont hafte rth erain yseaso ni nNigeria .Thi s isdirectl yafte rth eperio dtha tth ehighes tprevalenc eo f

107 flukeinfection si nslaughtersla b surveyswa sfound .Scot tan d Goll (1977)foun di nthei rexperiment swit hshee pan dFasciol a hepaticatha teg gsheddin gstarte daroun dNovember/December , whenth enumbe ro ffluke sfoun di nliver swer ea tthei r highest.Th ehighes tnumber so fegg swer eexcrete dbetwee n Februaryan dJune .

3.2.4. Remarkso nepidemiologica laspect so fliverfluk e infectionsi nth eWester nProvinc eo fZambia .

Inth eWester nProvinc eo fZambia ,som eresearc h intoth e snailpopulatio nha sbee ncarrie dou t (AnimalDiseas eContro l Project,1987 ,unpubl .data) .Th edistributio no fth esnai l population isrelate dt operiodicall y floodingrivers .Th é snailpopulatio ndecline si nth ecours eo fth edr yseaso nwit h thereductio ni nsiz eo fpool stha tar eforme dwhe nth eriver s areflooded .Sinc eth eflood sar estil lhig ha tth estar to f thedr yseason ,th epool sbecom esmalle rlate ri nth edr y seasontha nwa sreporte d forth eNigeria nsituatio ndescribe d bySchillhor nva nVee n (1980a,1980b) . Inthes epool s relativelyheav yconcentration so f (infected)snail sma yb e present.Hig hnumber so fcercaria ema yb edischarge d inth e pools,whil eincreasin gnumber so flivestoc kus eth epool sa s wateringpoint .Thes efactor shav ebee ndescribe d forshee pan d Fasciolahepatic ai nth eEthiopia nhighland s (Lemmae tal. , 1985).

Ofth ecattl etha tgraze dth eZambez ifloodplain si n Senangadistric t 50t o8 0% wer einfecte dwit hFasciol a qjqantica (Jorgensenan dKamukwai ,1977) . Infected liverswer e foundal lyea rthrough .Th elarges tnumbe ro finfecte dliver s wasfoun dbetwee nJanuar yan dJune .Silangw a (1972,1973 )foun d extremelyhig hprevalence so fliverfluk ei nabbatoi rsurvey so f Barotsecattl eslaughtere d inMongu ,Wester nProvince .O n average89. 6% o fal lliver swer econdemne dbetwee n194 4an d 1964. Of 192liver sexamine d inJanuar yan dFebruar y196 7an d 1968, 98.4% wer epositive .Thes epeak sar efoun daroun d2 t o3 monthsafte rth estar to fth erain yseason .Th ehig hprevalenc e mayhav ebee nrelate dt oth efact ,tha tth eliver swer e examined ina perio dwit hfavourabl econdition sfo rth e developmento fth eintermediat ehost ,a swa sindicate db y Jorgensenan dKamukwa i (1977).

Inth eWester nProvince ,grazin gth efloodplain so friver s isundoubtedl ya nimportan tfacto ri nacquirin g liverfluke infections.Th emajorit yo fth eanimal sgraz eth eplain so fth e Zambezirive ra tleas tpar to fth eyear .No tonl yth e

108 transhumantcattle ,bu tals olarg enumber so fth esedentar y herdsstayin go nth ehighe rground saroun dth efloodplain s grazeo ni tpar to fth eyear .Specificall y inth eperio d immediatelyafte rth efloods ,aroun dJul yt oSeptember ,th e animalsar eexpose dt oliverfluk einfections .Septembe r generallymark sth een do fth edr yseason ,whe nals oth e nutritionalconditio no fth eanimal si sworst .A swa sals osee n inNigeri ab yBabalol aan dSchillhor nva nVee n (1976),typica l acuteclinica lsign so fliverfluk einfection sca nb esee ni n cattlearoun dthi stim e (personalobservation ,ADCP ,1987) .

Jorgensenan dKamukwa i (1977)foun deg gsheddin g throughoutth eyea ri nth eWester nProvince ,bu tth ehighes t levelso feg gexcretio nwer efoun dbetwee nMa yan dAugust ,th e dryseason .Th eeg gsheddin gtherefor eseem st oincreas earoun d 2t o3 month safte rth epea kpercentag eo ffluk einfection s found inlivers .Thi sma yb erelate dt oth efac ttha t reinfectiondelay spatenc yo fliverfluk einfection s (Kendall andParfitt ,1975) .Egg srequir earoun d1 7day st ohatch ,afte r whichth eintermediat ehos tca nb einfected .Th edevelopmen ti n thesnail stake s7 5day si nth ewar mseaso nan d17 5day si nth e cold season (Soulsby,1968) .Wit heg gsheddin gpeakin g inth e WesternProvinc efro mMa yonwards ,th eperio dtha tsnail sar e dischargingth elarges tnumbe ro fcercaria ema ystar taroun d Augusto rSeptember .Th ecol dseaso ni nth eWester nProvinc e startsaroun dApri lan dlast stil laroun dJuly ,whe na ho t period starts.Thi sperio dma ytherefor ecoincid ewit hth e periodtha tcattl ear emos tlikel yt ob einfecte dwit h metacercariae,th einfectiv estage so fliverfluke .

Infigur e1. ,a diagra mi sshow no fth ehypothetica l interrelationsbetwee nris kfactor sinvolve d inth e epidemiologyo fFasciol agiaantic ainfections .I ntabl e1. , someo fth einfluence smentione di nliteratur ear egiven .Thei r possiblesignificanc efo rth eWester nProvinc ei sindicated .

3.3. Epidemiologicbackgroun do fintestina lparasit einfection s inAfrica .

Arelatio nbetwee nintestina lparasit einfection san d climaticcondition si ssuggeste db ysevera lauthors .Severa l phaseshav et ob edistinguishe dher ea swell :

- thesurviva lo fpre-infectiv ean dinfectiv estage soutsid e thehosts , thebehaviou ro fth eparasite si nth ehost ,includin gth e meanso fsurviva lthroug hunfavourabl eperiods ,th e

109 Figure1 . Diagram,showin gth etheoretica l interrelations betweenris kfactor srelevan t forth eepidemiolog yo f liverflukeinfection si nsub-Sahara nAfrica .

infection of Size of snail ils population

Concentration of snails

Floocfc>lain grazing

Chronic patent infection | Dry season

Peak in percentage of Wet season livers with flukes

effectso finfection so nth ehos tan dth ereactio no fth e hostt oinfection , thesheddin go fparasit eegg san dth econtaminatio no fth e pasture.

3.3.1. Parasitesurviva loutsid eth ehost .

Kaufmannan dPfiste r (1990)foun d inTh eGambi atha t N'Damacattle ,treate dan dwor mfre ea tth estar to fth edr y season,wer eno tre-infecte d inth ecours eo fth edr yseason ; outsideth ehost ,egg san dlarva ecanno tsurviv eth edr y season.Unde rhumi dcondition s (relativehumidit yo f8 0% )th e survivaltim eo flarva eo nth esoi lrange dfro mles stha nthre e weeksfo rHaemonchu st o9 week sfo rCooperi aan d Oesophaaostomumi na laborator yexperimen t (Lyakue tal. , 1988).Oko nan dAkinpel u (1982)indicate dtha trainfal li s critical inth esurviva lchance so fhelmint hegg san d

110 particularlyo flarvae ,an dtha ttemperatur ei so fles s importance.Magzou be tal . (1990)describ epastur einfection s ofcamel swit hhelminth si nth eSuda nan dfoun dlarva eo f Haemonchuso nth epastur eonl yi nth ewe tseason .Larva eo f Trichostronqylusspp .howeve rsurvive d fora perio dwel lafte r thewe tseason .The yappeare dt ob emor eabl et osurviv eunde r aridcondition stha nth elarva eo fHaemonchu sspp .

3.3.2. Theparasit ei nth ehost .

Thehos tbecome sinfecte dthroug h ingestiono fth e infectivestage so fth eparasites .Th eeffect so finfection s mayvary ,dependin go nth enumbe ro finfectiv elarva eingested , thespecie so fparasite singeste dan dth econditio nan dth eag e ofth ehost .Th ehistor yo fth ehos ti sals oo fimportance . Animalstha thav ebee nexpose dt oparasite sbefore ,ar e generally lessseverel yattacked .Afte rfirs tinfections ,th e hostsdevelo pimmunit yagains tth eparasites .Thi simmunit y providesresistanc eagains treinfectio n (Ploeger,1989) .

Theimmunity ,acquire dafte rfirs tinfection ,als oenable s theanimal st orejec tth einfectio ni nth elon grun .Th e acquired immunity ismor eo rles seffective ,dependin go nth e levelo fth efirs tinfectio nan do fsubsequen texposure ,an d morespecificall yo nth egenus .Ploege r (1989)indicated ,i n studiesi nDutc hdair ycattle ,tha tth eimmunit yagains t Nematodirusspp .i sver yeffective .Infection swit hthi s parasitetherefor egenerall yonl yoccu ri ncalves .Thi si s also,thoug ht oa lesse rextent ,tru efo rCooperi aSPP .an d Dictvocaulusviviparus .Provide dtha tanimal shav ebee nexpose d toinfectio nwit hthes eparasite si nthei rfirs tgrazin g season,the ywil lhardl ybecom ereinfecte dwit hthem ,an d clinicaleffect swil lb epracticall yunnoticed . Inadul t cattle,Ostertaqi aspp .an dTrichostronqylu sspp .ar emor e common.

Specifically inyoun gcalve sacut egastro-enteritis , resulting indiarrhoe ama yb ecause d (Ploeger,1989) . Ifth e numberso finfectiv elarva eingeste dar esmaller ,th eanimal s areolde ro rhav ebee nexpose dbefore ,th eclinica lsymptom s mayvary .I fth esymptom sar esubacute ,generall yn odiarrhoea , buta chroni cwastin gaccompanie db yanaemi a (Kaufmanan d Pfister,1990 )o rhypoalbuminaemi a (Rosse tal. ,1970 )i s found.I nchroni c infections,th eanimal sma yonl ysho wa slightly impairedbod ycondition .I ti swel lpossibl ei n chronic infections,tha tn oapparen tsigns ,tha tca nb e attributedt ohelmint h infections,ca nb eseen .

Ill Table1 . Climatic factorsrelevan tfo rth eoccurrenc eo f liverflukeinfection si nsub-Sahara nAfrica ,a s derived fromliterature .I nth ecolumn so nth eothe r Africanregions ,factor stha tma yb eo fcomparabl e importancei nth eWester nProvince ,Zambia ,ar e markedwit ha nasterix .

Factor Nigeria Mali Ethiopia Uestern (Babalolaan d (Tembelie t (Scottan dGoll , Province, Schillhornvan al., 1988) 1977, Lemmae t Zambia Veen, 1976, al., 1985) (Jorgensenan d Schillhornva n Kamukwai, 1977, Veen, 1980a, (sheep, Fasciola Silangwa, 1972, 1980b) hepatica, Lymnea 1973,ADCP , truncatula) 1987)

The sizeo fth epopulatio no fLymne a natalensisan dexposur eo flivestoc kt oinfectiv e metacercariae.

• 1 * Snail population ++ + ++ ++ growth inth erain y season * Floodplain grazing ++ + ? ++ * Dwindling sizeo f ++ ? ? ++ watering poolsi n thedr y season

Presenceo finfection s with Fasciola gigantica inlivestock . * Latedr yan dearl y ++ ? ? ++ rainy season infections with young flukes * Nutritional status ++ ? ? ++ and acute fasciolosis * Rainy seasonan d +2 ? ++ ++ levelo fadul t fluke infections

(continuedo nnex tpage. )

Insub-Sahara nAfric ath einfection soccu ri nth ewe t season.Pande y (1990)reporte do nth eresult so fabbatoi r surveysint oth eprevalenc eo fintestina lhelminth si n Zimbabwe.Bot hi nshee pan di ncattl eth ehighes tprevalenc e andleve lo finfectio nwa sfoun dtoward sth esecon dhal fo fth e wetseason .Kaufman nan dPfiste r (1990)reporte dheav y infections inth ewe tseaso ni nN'Dam acattl eo fTh eGambia .I n

112 (Table 1. continued.)

Factor Nigeria Mali Ethiopia Western Province, Zambia

Flukeeg gsheddin gan dinfectio no fth eintermediat ehost . * Peaki neg g +3 ? ++ ++ sheddingi nth edr y season 6 Peaki neg g •* ? +5 ++ sheddingi n relationt oth e peaki ninfectio n level

Factorconsidere d important Factor importantbu temphasi so frelatio ndiffer sfro mth eWester nProvinc e situation(se efootnotes ) Factorno tmentione d Exposureo flivestoc kmainl ydurin gdr yseaso nplai ngrazin g Highest levelo ffluk einfection sfoun da ten do fdr yseason/earl y rainyseaso n Peaki nlat ewe tseaso nan dearl ydr yseaso n Peakdirectl yafte rhighes t levelo ffluk einfectio n Levelo feg gsheddin gparalle lt oleve li nadul tfluke spresent ,pea kwel l afterth ewe tseaso n Highesteg gsheddin gsevera lmonth s latertha npea ki nadul tfluk einfectio n the dry season no adult Haemonchus contortus was found; the parasite survives the dry season as an inhibited larva inth e host. Cooperia survives as an adult in the host.

3.3.3. Egg shedding and pasture contamination.

Egg shedding patterns also follow the seasons,wit h the highest levels of egg shedding, often expressed by the number of eggs per gramm (EPG), found inth ewe t season. Chiejina and Emehelu (1986)describe d this forNigeria n cattle.Conno r et al. (1990) found this effect ingoat s inTanzania .Th e rainfall iso f great significance inth e egg shedding pattern, as indicated for goats inTanzani a by Connor et al. (1990) and for cattle inth e Transvaal region of South Africa by Malan et al. (1982). At the onset of the rains atth e start of the wet season,bot h authors report a sharp rise inth e faecal egg counts. The pasture becomes contaminated from that moment onwards. With the development of adult helminths inth ehost , the pasture contamination, and consequently the number of animals infected, aswel l as the level of the infections,

113 increases.I flarg enumber so fanimal sshar eth esam epasture , thecontaminatio n ismor eseriou stha ni fth enumbe ro fanimal s issmalle ran dth eare agraze d islarge r (Muenstermannan d Tome,1989 ,Eyske re tal. , 1990).

3.3.4. Remarkso nepidemiologica laspect so fintestina l helminthinfection si nth eWester nProvince .

Inth eWester nProvinc eo fZambi adetaile dresearc hint o theprevalenc eo fhelminth sha ssofa rno tbee ncarrie dout . Unpublisheddat a (Bongers,1987 )o nth eproportio no fdun g samplescollecte dthroughou tth eyear ,bein gpositiv efo r intestinalhelmint heggs ,d osho wa seasona lpatter ni neg g shedding,wit hth ehighes tproportio no fpositiv esample si n thesecon dhal fo fth erain yseason .

Figure2 .show sris kfactor stheoreticall y involved inth e epidemiologyo fintestina lhelmint hinfections .I ti slikely , thatresult sa sreporte dher efo rothe rpart so fAfric aappl y toWester nProvinc ea swell ,becaus eo fsimilaritie si n influenceso fclimati cfactors .Som eo fthes efactor san dthei r probablerelevanc efo rth eWester nProvinc ear egive ni ntabl e 2.Th erain yseaso ni sth emos tcritica lperio d forhelmint h infections.Th eparasite ssurviv eth edr yseaso neithe ra sa n inhibited larvao ra sa nadul ti nth ehost .Th einhibite d larvaewil lstar tdevelopin g intoadult swhe nth erain shav e started.I nthi sperio dpastur econtaminatio nstart st obuil d upan dth eamoun to finfectiv elarva eincrease si nth ecours e ofth erain yseason .Th enumbe ro fparasite si nth eanimal s willals oincreas ea sth erain yseaso nprogresses .A si n Nigeria (Okonan dAkinpelu ,1982) ,rainfal lma yb eth emos t critical factori ndeterminin gth esurviva ltim eo flarva eo n thepasture .Th elo wtemperature si nth ecol ddr yseaso n followingth erain yseaso nma yals ob ea factor .Th ewor m burdeni nth eanima li slikel yt ob elarges twhe nth edr y seasonstarts .

3.4. Researcho ninfluenc eo finfection so nproductivity .

Researchint oth eeffect so finfection swit hintestina l parasitesan dliverfluke so nproductivit y isgenerall y restrictedt oon-statio nexperiment swher egroup so fanimal s thatrespectivel ywer ean dwer eno ttreate dwit hanthelmintic s orflukicide sar ecompare dwit heac hothe runde rrelativel y welldefine dconditions .Fiel dexperiment sar egenerall y limitedt osmal lruminants .A consideratio n inthi sma ybe , that insuc hexperiment sth eanimal sar eofte nowne db yth e

114 Figure2 . Diagram,showin gth etheoretica l interrelations betweenris kfactor srelevan tfo rth eepidemiolog yo f infectionswit hintestina lhelmint hparasite si nsub - SaharanAfrica .

Survival ol larvae on pasture * Acute gastro-enteritis

Cailla population density [Age ol host 1 \ * ..„.^'^ s Pasture contamination y/ ^Wasting with patency

Chronic infection |Wet season | with patency

Immunity k- \» ' Survival of parasite |Dry season | 1Previou s exposure 1 as adull or as inhibited larva in the host

researchinstitutio nan dplace dunde rth ecar eo fregula rher d owners.Obviousl y iti scheape ri nsuc hcase st ous esmal l ruminantsfo rthis .

Inth eliteratur enamed ,th eproductivit ytrait sassesse d mostlyar egrowt han dweigh tgain ,growt hrate ,conceptio n ratesan dbirt hweight so fcalves .Mil kquality ,mil kyiel dan d feedconversio nar eals omentioned .

3.4.1. Liverflukes.

Considerabledifference si nth eeffect so finfection swit h liverflukeso nproductivit y aredescribed .Chic ke tal . (1980) founda clea rnegativ eeffec to fmoderat eFasciol ahepatic a infectionso nth egrowt ho f1 2mont hol dHerefor d steersi nNe w SouthWales ,Australia .Especiall yafte rth efirs t1 2week s

115 «* id

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Knappe tal .(1971 )however ,coul dno tidentif ynegativ e effectso flo wnumber so fFasciol ahepatic a (meannumbe ro f flukesrecovere d 6month safte rtreatmen twer e9. 6 for untreated controlsan d4. 4 fortreate danimals) .Weigh tgai n waseve nreduce d inanimal swit hnaturall yacquire d infections treatedwit hoxyclozanid ea ta dos erat eo f1 5mg./kg .bod y weight.Th efee dconversio nwa sslightl yhighe ri nth etreate d group (10.69k go ffeed/k go fweigh tgai na soppose dt o 9.84 forth euntreate d controls),an dth ecos to ffoo dpe rkg .o f growthwa shighe r ($0.6 9pe rk go fweigh tgain ,$ 0.6 4i n untreated controls).Knap pe tal .(1971 )di dno tdiscus sth e causeo fth efact ,tha ttreate danimal sdi dno tperfor ma swel l asth econtrols .The yconsidere dth edru gt ob ewel ltolerate d atth edos erat eused ,sinc en oadvers esign so ftoxicit ywer e observed.I twoul dseem ,tha tinapparen ttoxi ceffect sma y stillhav ebee npresent .Owe n (1984)coul dals ono tidentif y significantdifference si ngrowt ho fcalve stha twer e5 t o7 monthso fag ea tth estar to fth etria lwit hlo wlevel so f Fasciolahepatic ainfection si nPapu aNe wGuinea ,i ncompariso n withtreate danimals .Th eliverfluk einfectio nlevel swer e determinedb yintroducin g fluke-freetrace rcalve si nth eher d forthre emont hperiod san dsubsequentl ykillin gthe mt ocoun t thenumbe ro ffluke spresent .Th enumbe ro ffluke si ntrace r calvesneve rexceede d20 ,whic hi sconsidere dt ob ea lo wleve l ofinfectio n (Oakleye tal. , 1979).Th etria llaste d 18months . Itwa ssuggested ,tha tcompensator y foodintak emask sth e effect,o rtha tminera ldeficiencie sma yhav eplaye da part . Alsoth efac ttha tmos tdamag ei sdon eb yth eearl ystage so f theliverflukes ,whic har egenerall y lessaffecte db ymos t drugsma yb eth ereaso nfo rno tfindin gsignifican teffects . Thelo wleve lo finfectio nma yals ohav ecause dth elac ko f significance.

118 Oakleye tal .(1979 )describe dth eeffect so fFasciol a hepaticainfection si ndair yheifers .The yfound ,tha tth e levelo finfectio nwa sdeterminan t inth eexpressio no fth e effecto fth einfection .A grou po finfecte danimal shavin ga highleve lo fnutritio n (i.e.fe dt ogai n68 0gram spe rday ) neededmor econcentrat efee d (1,345kg. ,a soppose dt o 1,220 kg.i na perio do f32 6days )t oachiev ethei rconditio nan dha d a lowergrowt hrat etha nuninfecte dcontrol swit hth esam e nutritional status.Ove ra 32 6da yperio dth euninfecte d controlanimal sgaine d 698grams ,an dth einfecte d animals68 0 gramspe rday .Th esam econditio nwa si nsom ecase sno t reached.I na grou pwit ha lo wnutritio nleve l (inwhic hth e infected animalswer efe dth esam equantit yo fconcentrat ea s thehig hleve lcontro lgroup ,an dth euninfecte d animalswer e fedt omaintai nth esam elive-weigh tgai na sth elo wleve l infectedgroup )th edifference si ngrowt hrat ewer eles s pronounced,whil eth eFee dConversio nRat efo rConcentrate s (Cone.FCR )wa ssignificantl yinfluenced .Th eCone .FC Rfo rth e infectedanimal swa s5.90 ,an dfo rth efluk efre econtrol s 4.18.Th econceptio nrat ean dth ecal fbirt hweigh to fth ehig h levelcontro lgrou pwa ssignificantl yhighe rtha nal lothe r groups.Th econceptio nrat ewa s9 3% i nthi sgroup ,6 2% an d8 1 % inth einfecte dgroup san d8 1% i nth euninfecte d lowleve l group.Th ecal fbirt hweigh ti nth euninfecte dhig hleve lgrou p was4 2kg. ,a soppose dt o39. 0an d40. 2k gfo rth einfected , and36.2 5i nth elo wleve luninfecte dcontrol .

Blackan dFroy d (1972)foun da ninfluenc eo fFasciol a hepaticainfectio no nth equalit yo fmilk .Th eTota lSolid s contento fmil kwa smeasure donc ea month .I ncattl eherd s whereliverfluk e infectionswer epresent ,Tota lSolid sconten t was12.3 6% o naverag eove ra thre emont hperio d startingi n November.Afte rtreatmen twit hoxyclozanid ei nearl yFebruary , theaverag eTota lSolid sconten tove rth efollowin g5 month s was12.5 4% .I nuntreate dcontrol sth eaverag eove rth esam e5 monthperio dwa s12.0 8% .I nherd swher en ofluk einfection s werepresen tn oeffec to foxyclozanid eo nmil kqualit ycoul db e identified. Itwa sstated ,tha tth elive ri sinvolve di n metabolicprocesse s leadingt oth esynthesi so fmil kprotein , fatan dlactose .Thes eprocesse sma yb ehampered ,resultin gi n impairedmil kquality ,b yth edamag ecause db yth epresenc eo f liverflukes.Since ,however ,mos tcomponent so fmil kar e synthesised inth emammar yglan ditsel f (Dilse tal. ,1977 , Mepham,1977 ,Jones ,1977) ,a mor eplausibl eexplanatio ncoul d be,tha tth ereductio no fth emil ktota lsolid sconten t isa n exponento fth emor egenera leffect so fliverfluk einfections . Hypoalbuminaemiaan danaemia ,th eseverit yo fwhic hdepend so n

119 theseverit yo fth einfectio nan dth econditio no fth eanima l (Graber 1971),ar elikel yt ob einstrumenta li nthis .Th e effortst ocompensat efo rthes epathofysiologica leffect sma y affectth eavailabilit yo famino-acid san dfre efatt yacid si n thebloodstream .I tma yals ob epossibl etha tosmoti cchange s inth ebloo da sa resul to fth ehypoalbuminaemi aha sa direc t effecto nth esolid sconten ti nth emilk .

Apartfro mth edirec teffect so nth eproductivit yo f animals,th eeffect so ftreatmen to nth econtaminatio no fth e environment inwhic hanimal sliv ema yb eo fimportanc ei n liverflukeinfectio ncycles .Armou re tal . (1973)describe da reductiono fth epastur econtaminatio nthroug htreatmen to f sheepinfecte dwit hFasciol ahepatica .

Theeffect so fflukicide so nsevera lstage so fFasciol a hepaticaar ediscusse db yBora ye tal . (1983)an dPresident e andKnap p (1972).Bora ye tal .stresse dth eimportanc eo f efficiencyo fflukicide sagains tyoun ga swel la sol dstage so f liverfluke.The ystudie dresult so ftreatment swit h triclabendazole insheep ,infecte dthroug hintrarumina l injectiono f20 0metacercaria e (mediuminfectio nlevel )o r50 0 metacercariae (heavyinfectio n level).Th eefficienc ywa s measuredb ytreatin ghal fo fth eanimal san dretrievin gfluke s afterslaughte rfro mbot htreate dan duntreate danimals .Fro m thenumber so ffluke srecovere d frombot htreate dan duntreate d animalsth eefficienc yca nb ecalculated .A ta dos eo f2. 5 mg./kg.th eefficienc yo fth edru gagains t8 an d1 2wee kol d flukeswa s9 0an d9 8% respectively .A ta rat eo f5 mg./kg .th e efficiencywa s9 2% agains t4 wee kol dflukes ,9 8% agains t8 weekol dfluke san d10 0% agains tfluke so f1 2week so fage . Theefficienc yo ftriclabendazol edepende do nth edos erate , rathertha no nth eleve lo fth einfections .President ean d Knappdescribe dth eefficienc yo frafoxanid eagains tyoun g flukeso f6 week so fag ei nHolstein-Friesia n steercalves .Th e calveswer einoculate db ystomac htub ewit h20 0metacercaria e perda yfo r5 consecutiv edays .Hal fo fth ethre egroup so f1 0 animalswer einoculate dwit hcattl estrai nmetacercaria ean d theothe rhal fwit hshee pstrai nmetacercariae .On egrou pwa s useda scontrols ,whil eth eothe rtw ogreoup swer etreate da t doserate so f7. 5 and10. 0mg./kg .bod yweigh trespectively . Theefficienc y foundi nthi sexperimen twa s58. 8% agains t6 weekol dflukes .N odifferenc ewa sfoun dbetwee nth edos e rates,whil eth edifference si nefficienc ybetwee nth estrain s offluke swer einconclusive .Bot hreference sd ono tdiscus sth e reasonfo rth efac ttha tyoun gstage so ffluke sar eofte nles s affectedb ydrug stha nolde rstages .Ther ema yb ea relatio n

120 withth edru greachin gtherapeuti cconcentration s inth ebil e system,rathe rtha ni nth ebloo do r (liver)tissue .Olde rfluk e stagesliv ei nth ebil esystem ,whil eyoun gfluke smigrat e predominantlythroug hth eparenchym ao fth eliver ,an dma y thereforeb eles sexpose dt othes etherapeuti cconcentrations .

Productivityeffect so fFasciol agiaantic ahave , apparently,rarel ybee nsubjec to fresearch .I ti sassume dtha t Fasciolagiaantic aproduce ssimila reffect sa sFasciol a hepatica.Clinicall yan dpathologically ,th eeffect so fth e presenceo fFasciol agjgantic ainfection si ncattl ear eindee d comparable,althoug hacut efasciolosis ,a sreporte db yBabalol a andSchillhor nva nVee n (1976),an da sobserve d inth eWester n Province,i srarely ,i fever ,reporte d incattl eresultin gfro m Fasciolahepatic ainfections .

3.4.2. Intestinalhelminths .

Inman ycase sresearc h intoth eeffect so fintestina l parasiteso nproductivit y iscarrie dou tb yevaluatin gth e effecto ftreatmen to ngrowth .Abdall a (1989)studie dth e effecto ftreatmen twit hAvermectin eo nth egrowt hrat eo f stabledcalve san dshee pi na non-statio ntrial .Th etreate d animalsha da highe rgrowt hrate ,bu tth edifference swer eno t significant,probabl ybecaus eo fth erelativel y smallsiz eo f thesampl ean dth eshor tduratio no fth etrial .Bianchi nan d Honer (1987)not ei nthei rrevie wo fresearc ho nproductivit y andintestina lparasite si nfiel dexperiments ,particularl yi n extensivelymanage dNellor ecattl ei nth eCerrad oregio ni n Brazil,tha ta positiv eeffec to ftreatmen to ngrowt hcoul db e found.Als oChiejin aan dEmehel u (1986)foun dfavourabl e effectso ftreatmen to ngrowt hi nNigeria ncattl ei na non - stationtrial .Eac ho fth etreatmen t schedulesteste d improved thegrowt ho fth eanimal ssignificantly .Kaufman nan dPfiste r (1990)foun dbette rgrowt ho fN'Dam acattl ean da lowe rweigh t lossdurin gth edr yseason .Th edail ygrowt hrat eo ftreate d animalswa s40 3gr .pe rday ,an dtha to funtreate dcontrol swa s 270gr .pe rday .Th eweigh tlos sdurin gth edr yseaso nwa sno t quantified inthi spaper .Paren tan dSam b (1984)compare d Avermectinean dTetramisol efo rthei rinfluenc eo ngrowt ho f Zebu-N'Damacros scalve si nSenega lan dfoun da considerabl e differencebetwee nth etw odrugs ,Avermectin eprovin gth emos t effective inimprovin gth egrowth .I nthi son-statio ntrial , overa perio do f12 0days ,th eweigh tgai ni na grou ptreate d withAvermectin eprove dt ob e7.6 4k ghighe rtha ntha ti na grouptreate dwit hTetramisole .Th einitia lmea nweight so fth e twogroup swer e99.4 2k gan d97.2 9k grespectively ,an dth e

121 meanweight safte r12 0day swer e141.0 4k gan d132.2 8k g respectively.

DeRon de tal .(1990 )no tonl yevaluate dth eeffect so f Avermectinean dFebante lo ngrowth ,bu tals oo nag ea tfirs t service,mil kyiel dan dEPG .Thi sstud ywa sdon ei nDutc h Friesiandair ycattl ei nSr iLanka .O nth ebasi so fgrowt hpe r day,th eperio dnecessar yt oarriv ea ta bod yweigh to f23 0 kg.,a twhic hweigh tth eanimal swer esire dfo rth efirs ttime , wascalculated .Afte rtreatmen twit hAvermectine ,th eage ,o r ratherth eweigh tfo rfirs tservic ewoul db ereache d9 6day s earliertha ni nuntreate danimals .Afte rtreatmen twit h Febantel,thi sweigh twoul db ereache d4 3day searlier .Th e milkyiel dwa simprove db y11 2kg .th eFebante ltreatment ,an d 118kg .fo rth eAvermectin etreatment ,ove ra perio do f13 3 days.Th ebenefit so freduce dag ea tfirs tservic ean dimprove d milkyiel doutweighe dth ecos to fth edrugs .

Connore tal . (1990)noted ,tha tgoat sreceivin gtreatmen t againstinterna lparasite si nTanzani aha da considerabl y bettergrowt hrat etha nuntreate dcontrols .Treate danimal s weighed 13.32k go naverag e2 2week safte rth estar to fth e treatmentschedule ,an duntreate dcontrol sweighe d 11.94kg .o n average.Aroun dth estar to fth eschedul eth eaverag eweight s inbot hgroup swer earoun d 10.5kg .Huensterman nan dTom e (1989)foun dimprovemen to fgrowt hi ntreate dshee pan dgoat s inon-statio nexperiment si nKenya .I na tria lperio dlastin g fromSeptembe r198 5t oApri l198 6treate dgoat san dshee p gained9. 4 kg.o naverage ,an duntreate dcontrol s7. 3 kg.o n average.I na secon dphase ,betwee nMa y198 6an dNovembe r1986 , untreatedanimal sgaine d 1.8kg. ,an dtreate danimal sgaine d 3.5kg .

Ploeger (1989)studie drelation sbetwee nth eproductivit y parametersgirth ,bod yweigh tan dmil kproductio nan dinfectio n levelso fintestina lparasites ,measure do nth ebasi so f serology,eg gan dlarva lcount si nfaeca lsample san d pepsinogenvalue si nseru msamples ,i nfiel dstudie si n commercialdair yherd si nTh eNetherlands .Severa lag e categorieswer einclude d inth estudies .Apar t fromsignifican t relationsbetwee ninfectio nlevel san dnegativ einfluence so n growth,liveweigh tan dmil kproduction ,positiv einfluences , particularlyo ngrowth ,i nth esecon dgrazin gseason ,wer e foundo finfection si nth efirs tgrazin gseason .Thi swa sth e resulto fimmunit yacquire ddurin gth efirs tseason .Barge ran d Gibbs (1981)foun d ina nexperimenta l settingtha tdair ycow s infectedwit h15,00 0infectiv etrichostrongyli d (Ostertaaiaan d

122 Cooperiaspp. )produce d2.1 6kg./da yles smil ktha nuninfecte d controls.Th eexperiment swer ecarrie dou twit hHolstei nan d Jerseycattl ei nth eUSA .

3.5.Discussion .

Inth eepidemiolog yo fbot hFasciol aaicrantic aan d intestinalhelmint hinfections ,th emanagement ,th eenvironmen t andth eseasona lvariatio nappea rt ob eo fimportance . Management factorsma yinclud eth echoic eo fwaterin gpoints , particularly forliverfluk einfections ,o rth echoic eo f pasture,mainl yfo rintestina lhelmint hinfections .Han ddu g waterpondso rwell sma yb ea les ssuitabl ehabita t forth e intermediatehos to fth efluke stha nperiodicall y flooded riverloopsan dpools .Heavil ygraze dpasture sar emor elikel y topos ea threa to finfectio nwit hintestina lhelminth stha n pastureswit hlo wdensitie so fcattle .

Floodplaingrazing ,mostl yassociate dwit hth edr yseason , isinstrumenta l inth eexposur eo fcattl et oinfection swit h liverflukes.I nth eWester nProvinc eo fZambia ,th eus eo fth e floodplainsfo rgrazin g isno tjus trestricte dt oth edr y season.I nth ecentra lplains ,th eanimal sgraz eth e floodplainsfo rth elarge rpar to fth eyear .Normall ythe yar e onlymove dou twhe nth ewater sris eto ohig htoward sth een do f thewe tseason .Th eflood ssubsid ei nth ecours eo fth edr y season,an dth eanimal swil lb etake nbac kt oth eplain sa s soona sth ewater shav egon edow nfa renough .Fro mtha tmomen t onwards,normall y fromaroun dJun eo rJuly ,th ehighes t exposurei slikel yt otak eplace ,als obecaus eth eintermediat e hostconcentrate si neve rsmalle rpool so fstagnan twater .I n thesouther nplains ,alon gth eNamibia nborder ,th eanimal sar e movedt oth eplain si nsearc ho fwater ,an dar emove dou tagai n assoo na sth erain shav estarte dan dpool sdevelo po nhighe r ground.I tma yb epossible ,tha tpea kexposur etake splac emor e strictly inth edr yseaso ni nthes eplains ,an dtha tth e exposurema yb emor eprolonge d inth ecentra lplain .

Inintestina lhelmint h infections,th ewe tseaso nseem st o beo fgrea t importance.Afte rhavin gsurvive dth edr yseaso ni n thevertebrat ehost ,eithe ra sa ninhibite d larvao ra sa n adult,th einfection sbecom epatent ,i.e .th eparasite sen d theirinhibite d stages,mature ,an dstar tproducin geggs ,whe n therain sstart .Afte rth efirs tinfectiv estage shav e developedo npasture ,th eleve lo fth einfection s inth ehost s startst oincrease ,a swel la sth enumbe ro fanimal sinfected . Withthes einfection sbecomin gpatent ,th econtaminatio no fth e

123 pasturesincrease si nth ecours eo fth ewe tseason .I nth e secondhal fo fth ewe tseaso nth eris ko fexposur ei sa tits ' peak.

* Strategictreatmen tagains tintestina lnematode sa swel l asliverfluke sshoul dai ma ttw omai ngoals .Firstly ,i tshoul d cleara nanima lfro ma ninfection ,secondly ,i tshoul dreduce , orrathe rprevent ,th econtaminatio no fth epasture .

Toddargued ,tha ttreatmen to fanimal sagains t intestinal nematodesi na nenvironmen t inwhic hthe yre-infec tthemselve s againi suseles s (Anon.,1979) .Grabe ran dPerroti n (1983) suggestedon etreatmen tagains tintestina lnematode sa tth een d ofth ewe tseaso nt opreven tth esurviva lo finfection s inth e animalsthroug hhypobioti clarvae ,an don etreatmen ta tth een d ofth edr yseaso nt opreven trecontaminatio no fth epastures . Itcoul db econsidere dt ogiv eextr atreatment sdurin gth edr y seasoni norde rt oreduc eth eweigh tlos sincurre ddurin gtha t period.Chiejin aan dEmehel u (1986)o nth eothe rhand , discussedtreatmen t schedulesi nwhic hth eemphasi swa splace d onwe tseaso ntreatments ,becaus eth ere-infectio nchance sar e greatestdurin gtha tperiod .Th ebasi cargumen tfo rth e recommendationo ftreatmen t inthi scas ei sth epresenc eo fth e parasites,an dhenc eimpaire dhealth ,an dth ebeneficia leffec t ofroutin etreatment so ngrowth .Preventio no fpastur e contamination isa fa rles simportan tai mi nthi scontext .I t canb eargued ,tha tregula rtreatments ,aime da treducin gth e levelo fth einfectio ni nanimals ,withou tcausin gcomplet e sterility,ca npreven theav yadvers eeffect so fth epresenc eo f theparasites ,whil ea tth esam etim eallowin gth eanimal st o developa goo dpremunity ,base do nregula rre-infection .A swa s alreadymentioned ,Ploege r (1989)foun dclea rindication stha t previousinfection sreduce dth eseverit yo fth econsequence so f subsequentinfections .

Inth eWester nProvince ,attempt sa tpreventio no fth e contaminationo fth epastur ethroug htreatmen t isno tlikel yt o producean yresults .I tcoul donl yproduc eeffec ti fal lherd s usingth esam ecommuna lgrazin gground swoul d followth e treatment schedule,bu teve nthen ,severa lo fth eparasit e speciesma yhav ereservoir si nwil danimal sgrazin gth esam e land.Treatmen t shouldtherefor eonl yb egive ni fa neffec to n theanima litsel fi spursued .Treatmen tschedule sshoul d concentratei nth esecon dhal fo fth erain yseason ,whe n pasturecontaminatio n isbuildin gu pan dth echalleng ei s highest.A treatmen t justafte rth erain yseaso ncoul dallo w theanima lt odispos eo fan yadul twor mburden .Thi scoul d

124 probablyreduc eth esiz eo fth eweigh tlos sincurre ddurin gth e dryseason .

Strategictreatmen tagains tliverfluke si softe n associatedwit hth eperio do fth eyea rmos tsuitabl et oreduc e theinfectio no fth eintermediat ehost s (Armoure tal. ,1973 , Simpsone tal. , 1985). InEuropea ncattl ean dshee pi ti softe n recommendedt oappl ya treatmen tagains tFasciol ahepatic ai n theearl ywinte rperio d (Blackan dFroyd ,1972 ,Horchne re t al., 1970),whe nth eanimal sar establed ,i.e .aime da t preventingpaten tinfection sa tth estar to fth egrazin g season.Scot tan dGol l (1977)treate d sheepi nth eEthiopea n Highlandsagains tFasciol ahepatic ai nNovembe ran dJanuary . Thewe tseason si nthi sregio nbegi ni nJun ean dlas tuntil l September.A shor twe tseaso nappear si nMarch .Owe n (1984) carriedou ta nexperimen twit hcalve si nPapu aNe wGuinea ,int o theeffect so ffiv edifferen ttreatmen t schedules.Onl yth e resultso fa schedul ei nwhic htreatment swer egive nonc eever y threemonth sapproache d significance.Armou r (1981)mentione d thistreatmen t schedulea sth emos tappropriat e forth e treatmento fliverfluke si ntropica lcattle .

Inth eWester nProvinc ea seasona lpatter ni nth e infectivecycl eo fFasciol agigantic aexists .A swa salread y stated forintestina lhelminths ,designin ga strategi c treatment scheduleagains t liverflukesi sno tlikel yt ob eo f greatsignificanc ei nreducin gth eris ko fliverfluk e infections,sinc eth epasture san dwaterin gpoint sar e communallyused ,an dinfecte dgam eus eth esam epasture san d wateringpoints .Th eai mo ftreatmen tshoul dtherefor eb et o keepth einfectio na ta moderat elevel ,allowin gth eanimal sa t thesam etim et oincreas eth eresistanc eagains treinfectin g youngflukes ,bot hthroug hpremunit yan dthroug hchange si n livertissu e (Kendallan dParfitt ,1975) .Mainl ybecaus eo fth e facttha tinfection soccu rthroughou tth eyear ,th eschedul e recommendedb yArmou r (1981)an dprove neffectiv e forFasciol a hepaticab yOwe n (1984)woul dprobabl yb eth emos tappropriat e forth eWester nProvinc ea swell .

Aninfectio nwit hintestina lnematode so rliverfluke sma y bea nimportan t factoraffectin gproductiv epotentia lo f livestock.I ti showeve rb yn omean sth eonl yfacto r influencingperformance .Productivit yo ftraditionall ymanage d livestock inAfric ai shighl yrelate dt oth eseasons ,th e qualityo fth eforag ean dth emanagemen tabilitie so fth e farmer.Malnutritio n (Troncy,1989) ,o rrathe ra suboptima l nutritional status,ca ni nitsel fb eth eresul to fal lthes e

125 factorsmentioned .A lo wleve lo fnutritio nma ymas k subclinicalinfection s (fasciolosis:Oakle ye tal. , 1979). Environmentalcircumstance sar etherefor ea tleas ta simportan t asth epresenc eo fth eparasite si nconsiderin gth enecessit y andviabilit yo fregula rtreatments .

Theinpu ti ntraditiona llivestoc ksystem si sgenerall y low, comparedt oth ebenefit s (Baars,1987) . Ifextr ainput s areneeded ,th ebenefit sresultin gfro mthes einput sshoul db e clear.Th eobjective so flivestoc kkeepin gi ntraditiona l systemsdetermin et osom eexten twhic hbeneficia lresult so f treatmentar econsidere d important.Beneficia leffect so f treatment shouldb eeasil ymeasurable .Treatment sar eonl y economically justifiablei fth ecost sar eoutweighe db yth e improvements.I nth ebenefi tdefinition suse db yBaar s (1987) theher d increase,an dth eresultin gimprove davailabilit yo f animals (forsales ,barters ,an dprobabl y fordraugh tpower , milkan dmanur esupply )i slikel yt ob eth emai nfeatur et ob e studiedt odetermin ewhethe ra neconomi cgai ni st ob ederive d fromroutin etreatments .

AsD eLeeu w (1990)discusse d forexample so fpastora lan d agro-pastoral systemsi nsevera larea si nsub-Sahara nAfrica , andMatthewma n (1980)discusse d forth eZambia nsituation , farmerswil lgenerall yai ma tincreasin gth esiz eo fthei r herds,o rrather ,a treducin gth erisk so fdecreasin gher d size.Reducin gmortalit yan dimprovin greproductiv eperformanc e istherefor eo fgreate r importancetha noptimizin ggrowt hrat e ofindividua lanimals .Growt hrat ea ssuc hi shardl yo f importance.I nth eWester nProvinc eo fZambia ,supplemen t feedingo ftraditionall ymanage dcattl ei srarely ,i fa tall , done.Animal sar eno tprimaril ykep tfo rsale ,an dmos tanimal s willb esol da ta nadvance dage .N ospecia leffort so rinput s areneede d forth eanimal st oreac hthei radul tweight . Improvedgrowt hrat ei showeve ro findirec timportance ,sinc e theag eo fsexua lmaturit y isa functio no fgrowt h (Ogink, 1993, p.27,Peters ,1983) ,an dthi si srelate dt oth eag ea t firstcalving .

Sincematin g isnormall yno tsupervised ,bu ti slef tt o naturei nth etraditiona lcattl ehusbandr y system inth e WesternProvince ,decreasin gmortalit y islikel yt ob ea mor e obviousan dvisibl eresul to ftreatmen t forth eWester n Provincecattl eowne rtha nimprovin greproductiv eperformance . Fromth epoin to fvie wo fth ecattl eowne ri ti stherefor e probablyth emos timportan tparameter .

126 Nevertheless,increasin greproductiv eperformanc eremain s animportan tprerequisit ei nvie wo fth egenera lai mo f increasingth eher dsize .Increasin greproductiv eperformanc e canb eexpresse db yth eincreasin gnumbe ro fcalve sbein gbor n peruni to ftim ean dlowerin gth eag ea tfirs tcalving . Parameterst oindicat eth eincreasin gnumbe ro fcalve sar eth e calving interval,expresse da sth eperio dbetwee nth ebirt ho f acal fan dth ebirt ho fth enex tcal fo fth esam ecow ,an dth e calvingpercentage ,expresse da sth enumbe ro fcalve sbein g borndurin gth eyea rdivide db yth enumbe ro fcow spresen ti n thesam etim espan .

Increaseo fth eher dsiz ean dgrowt hrat eo fanimal sar e bothvalue stha twoul db erelativel yeas yt oquantif yi n economic sense.Th ecost-benefi trati oo ftreatmen tpolicie s canb ederive d ina simpl emanne r fromthes easpects . Longitudinal studiesint othes ebenefit sar ea wa yo f determiningth eeffec to ftreatmen tunde rfiel dconditions .I n fieldresearc h inth eWester nProvinc eo fZambi aint oth e effectso fregula rtreatment sagains tintestina lnematode san d liverflukeso nproductivit ythes efactor swer etherefor e envisaged forevaluation .

Inth etrial scarrie dou tfo rthi sresearch ,th etreatmen t scheduleswer eprimaril yaime da treducin gth eleve lo fth e infectionso fintestina lparasite san dliverfluke sa smuc ha s possible,i norde rt oevaluat eth eeffect so nth eproductiv e parametersmos teffectively ,give nth eloca lcondition san dth e facttha tth echoic ewa smad et ocarr you tfiel dtrials ,rathe r thanon-statio ntrials .Sinc ei ti sno tlikel ytha tan y advantagei sgained ,i fa treatmen tschedul eagains tliverfluk e infectionsi sbase do nth eseasona lpattern ,fo rth eliverfluk e infectionsa schedul eo ffou rtreatment sa yea ra tthre e monthly intervalswa sused .Fo rth eintestina lhelminth sa seasonalvariatio ni nth eeffect so finfectio nwa sexpected . Therefore inth etrial sinvolvin gtreatment sagains tintestina l helminthsa schedul ewa sused ,i nwhic htreatment swer egive n atsi xwee kinterval si nth erain yseaso nan da tthre emont h intervalsi nth edr yseason ,si xtreatment sa year .

Whetherth etreatmen tschedule sa suse d inth etrial sar e alsosuitabl efo rpractica luse ,ca nb eevaluate do nth ebasi s ofth eeffect san dth ecost so fth etreatment .I ti slikely , thata treatmen t schedule,aime da treducin gth econsequence s ofinfection s forth eanimal ,shoul db eles sintensiv etha n thatuse di nth etrials .Thi sma yparticularl yb eth ecas efo r thetreatmen t againstintestina lhelminths .Th eeconomi c

127 viability of the treatment schedule of choice remains a critical issue.

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26. Kendall, S.B., and J.U. Parfitt (1975).Chemotherap y of infection with Fasciola hepatica incattle .Vet.Rec .97 ,9-12 . 27. Knapp,S.E. ,M.U .Schlegel ,P.J . Presidente and J.N.Armstron g (1971). Effect of oxyclozanide on feed efficiency incattl e with chronic fascioliasis.Am . J. Vet. Res., 32,1583-1587 .

28. Leeuw, P.d e (1990). Interactive effects of environment, management and mortality on cattle productivity in livestock systems insub-sahara nAfrica . Proc.6t h Int. Conf.AITVM , Uageningen, theNetherlands ,28t h Aug.-1st Sept. 1989. 29. Lemma, B., F.Gabre-a b and S.Tedl a (1985). Studies on Fascioliasis infou r selected sites inEthiopia .Vet .Paras .18 ,29-37 . 30. Liddel, J.S. (1972). Control of fascioliasis inbee f cattle by themolluscicid e Frescon and the resultant effect on productivity and itseconomi c implications. Proc.VI I Intern.Meetin g onDisease s of Cattle.Wld .Ass .Buiatrics , London, 183-203. 31. Lyaku, J.R.S., J.Monra d andA.A . Kassuku (1988). Larval ecology of bovine strongylid worms in tropical soils. I. Invitr o studies on the longevity of infective strongylid larvae indifferen t soil types.Trop .Anim . Hlth Prod.20 ,

129 190-192. 32. Malan, F.S.,R.K .Reineck e and N.A.Rope r (1982). Theseasona l incidenceo f helminth parasites of cattle inth eEaster n Transvaal Louveld. J. S.Afr .Vet . Ass. 53 (3), 179-184. 33. Magzoub,H. ,E.M .E l Hassan and H.J. Buerger (1990). Pasture infestation with Trichostrongyleso f camels inth eButan a area ofEaster n Sudan.Trop .Anim .Hlt h Prod. 22,7-8 . 34. Matthewman, R.U. (1980).Anima l disease control, Zambia, cattle production and health. FAO report AC:DP/ZAM/77/002. 35. Mepham,T.B . (1977).Synthesi s andsecretio n ofmil k proteins. In:M .Peaker , Ed. Comparative aspectso f lactation.Th e Zoological Society of London.Academi c Press Inc.,London , New York.pp .57-75 .

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131 CHAPTER4

Interventionstud y

133 4.1.Th eus eo fa her dmonitorin gprogramm e forth eevaluatio n ofth einfluenc eo fantiparasiti ctreatment so nth e productivityo ftraditionall ymanage dcattl ei nth eWester n Provinceo fZambi a I:intervention swit hTriclabendazol ean d Rafoxanide.

E.G.M.va nKlink 1,L .Schoonman 1,E.M .Chiposa 1an dC .Mwango 1.

Introduction.

Inth eWester nProvinc eo fZambi ath eliverfluk eFasciol a qiqanticai spresen ti nmos to fth ecattle ,a si sillustrate d byth eresult so fsurvey so fliver sa tabbatoirs ,wher eove r9 0 percento fth eliver swer epositiv e (Silangwa,1972 ,1973) ,an d studiesint oeg gdeposition ,wher ebetwee n5 0an d8 0percen to f theanimal sappeare dt oexcret eeggs ,dependin go nth eseaso n (Jorgensenan dKamukwai ,1977) .Liverfluk einfection scan , withoutcausin gclinica ldisease ,impai rth eproductiv e performanceo f livestock.Babalol aan dSchillhor nva nVee n (1976)mentione dgenera lweigh t loss,lowere dmil kproductio n andimpaire dreproductiv eperformance ,withou tquantifyin g thesevalues ,an dth edirec tfinancia l lossa sa resul to f massive livercondemnations .Blac kan dFroy d (1972)discusse d theinfluenc eo fliverfluk einfection so nth equalit yo fmilk . Simpsone tal . (1985)argue dtha ti nfinancia lterm sth e benefitso ftreatmen tagains tliverfluke soutweig hth ecosts , onth ebasi so fcost-benefi testimate sderive dfro m questionnairesamon gsevera lproductio nan dveterinar y specialistsi nFlorida ,USA .Th ebenefit swer ederive dfro m estimatedreduction si ndeat h loss,weigh tlos san d reproductive loss (lossi ncal f crop).

Inthi spape rth equestio ni sadresse dwhethe ri ti s possiblet oevaluat eth eeffec to fflukicid etreatment so n productivityb ycarryin gou tfiel dstudie swit ha clinica l nature,wit hth eus eo fa her dmonitorin gprogramme ,tha tha s beenuse d forth eassessmen to fgenera lproductivit ydat a (Van Klinke tal. , 1994a-d),give nth elogisti cdifficultie so f working ina rura lare awithi nth eframewor ko fa livestoc k developmentprojec t (DeRooi jan dWood , 1990).Apar tfro mth e treatment,th eag eo fth eanimal san denvironmenta laspect s sucha sth eGrazin gManagemen tSyste man dseaso nwer einclude d inth eanalysis .

department of Veterinary and Tsetse Control Services,Wester nProvince ,Zambia .

135 Materialsan dmethods .

Areaan dclimate .

Adescriptio no fth eare ai nwhic hth etrial swer ecarrie d outan dth eclimat eha sbee ngive nb yVa nKlin ke tal .(1994a) . Herdsbase d inth eGrazin gManagemen tSystem s (GMS)1 an d2 wereuse d inth einterventio ntrials .Bot har etranshuman t systems,meanin gtha tth eherd sgraz eth efloo dplai no fth e Zambezirive rpar to fth eyear ,wher ethe yar eexpose dt ofluk e infections (Jorgensenan dKamukwai ,1977) .The yar emove dove r adistanc eo f1 0t o4 0kilometer st ohighe rground sfo rth e resto fth eyear .I nGM S1 th eanimal sgraz eth efloodplain s forth elarges tpar to fth eyear ,movin gou to fth efloodplain s whenth erisin gwate rforce sthe mt od oso .I nGM S2 th e animalsonl ygraz eth efloodplai ni nperiod stha t watershortageso nhighe rground sforc ethe mt osta yclos et o theriver .

Experimentalherd san dtreatmen tschedule .

Atota lo f6 privatel yowne dtraditionall ymanage dherd s ofcattle ,maintaine d inth eGrazin gManagemen tSystem s mentioned (threei neac hGMS )i nth eWester nProvinc eo fZambi a wereinvolve d inth eflukicid einterventio ntrials .Fo rfiel d logisticreason san dbecaus eo fth edesire d intensiveleve lo f supervisionth enumbe ro fherd sinvolve d isfairl ysmall .Th e herdswer emonitore ddurin gth ecomplet etreatmen tperiod , usingth eautomate dher dmonitorin g systemdescribe db yVa n Klinke tal .(1994a) .Th emonitorin gwa scarrie dou tthroug h two-weeklyvisit sb yVeterinar yAssistant san dthree-monthl y visitsb yDistric tVeterinar yOfficers ,aide db ycompute r producedchecklists .

Becauseo fth erelativel y smallnumbe ro fherd sinvolve d inth etrials ,i twa sno tpossibl et oachiev esampl esize s largeenoug ht oallo wdemonstratio no frealisti cstatistica l differencesi nvalue so fparameter sexpresse da sproportions . Theywer eexpecte dt ob elarg eenoug ht odemonstrat e statisticaldifference si nvalue so fparameter sexpresse da s means.

Split-herdtrial swer econducted ,an da contro lan da treatmentgrou pwithi neac ho fth esi xherd swa sformed ,b y rankingth eanimal saccordin gt oage ,withi nth esexes ,an d assigningthe malternatel yt oeithe rth etreatmen tgrou po rth e controlgroup .Treatmen tan dcontro lgroup swer egraze d

136 together.A treatmen tschedul ewit hTriclabendazole 2wa s applied inth etreatmen tgroup so fthre eo fth eherds ,an don e withRafoxanide 3wa sapplie dt oth etreatmen tgroup si nth e threeothers .Treatment swer egive nfou rtime sa yea ra t intervalso fthre emonths .Th edosag eo fth etreatment swa s determinedo nth ebasi so fweigh tassessment susin gth egirt h measurementsan da girth-weigh tconversio ntabl edevelope dfo r cattlei nth eWester nProvinc e (Corten,1988) .Th eexac t treatmentdate swer eplanne db yth eDistric tVeterinar y Officerso fth edistrict si nwhic hth eherd swer ebased ,bu t thetreatment swer ealway sgive nwithi na perio do ftw oweek s inth emonth sFebruary ,May ,Augus tan dNovember .Th e treatmentsstarte di nFebruar y198 9an dcontinue dunti lAugus t 1991.Statistica lanalysi swa sbase do nth eresult srecorde d between1s tAugus t198 9an d31s tJul y1991 .

Forth eanalysi so fth eproductiv eperformanc eal lanimal s belowth eag eo ftw oyear san dal lfemal eanimal swer einvolve d inth etrial .A tth estar to fth esurve yperiod ,i nAugus t 1989,aroun d40 0animal swer einvolve d inth eTriclabendazol e trial,an daroun d30 0i nth eRafoxanid etrial .Newbor ncalve s wereautomaticall y assignedt oth esam egrou pa sth emother , eithertreatmen to rcontrol .Th etreatmen tperio d started6 monthsearlie rtha nth esurve yperiod ;i nthi smanne ra possiblestart-u pperiod ,i nwhic hth etreatmen t shoulddevelo p itseffect ,wa skep toutsid eth eanalysis .Fo rthi sreaso ni t wasdeeme dnecessar yt oassig nne wentrie sfro moutsid eth e herdst oth econtro lgroup ,assumin gthat ,sinc ethes eanimal s normallyoriginate d fromherd si nth esam eenvironment ,the y wouldhav eha da comparabl eexposur et oliverfluk einfection s beforeenterin gth eherd .Th etota lnumber so fanimal stha t wereinvolve d inth etreatmen tan dcontro lgroup sdurin gth e completesurve yperio dwer e23 4treate dan d26 0contro lanimal s forth eTriclabendazol etrial ,an d13 0treate dan d22 3contro l animalsfo rth eRafoxanid etrial .

Recordstake nan dparameter smeasured .

Duringth etwo-weekl yvisit sth eVeterinar yAssistant s recordedal lchange stha toccurre d inth ecompositio no fth e herds;births ,ne wentries ,removal sthroug hdeath ,sales , slaughters,wit hth edate so nwhic hth eevent stoo kplace ,an d

2Fasinex;Ciba-Geig yLtd. ,Basle ,Switzerland .

3Ranide; Merck, Sharpe and Dome, Haarlem, The Netherlands.

137 thedate sa twhic hfarmer sstarte dt omil kanimals ,whe nthe y stoppedmilking ,an dwhe ncalve sstoppe dsuckling .Durin gth e three-monthlyvisit sth eanimal si nth etreatmen tgrou pwer e treated,th egirt ho fal lanimal swa smeasure dan dth e informationgathere db yth eVeterinar yAssistan twa schecke d againstth echecklists .Faeca lsample swer etake na teac hvisi t of5 animal sfro mth econtro lgrou pan d5 animal sfro mth e treatmentgrou pfo rexaminatio no nth epresenc eo fliverfluk e eggs.Fo rth econcentratio no fth eeggs ,sieve swit hdecreasin g meshsize swer eused .Th efaeca lsample swer escore dpositiv e ornegativ efo rth epresenc eo ffluk eeggs ,an dth enumber so f eggswer ecounted .Sample swer econsidere dt ob epositiv ei fa t leaston eeg gwa sfound .

Becauseo fth enegativ einfluenc eo fliverfluk einfection s onproductivit y (Babalolaan dSchillhor nva nVeen ,1976 , Simpsone tal. , 1985),mainl yo ngrowt han dweight , reproductiveperformance ,mil kproductio nan dgenera l condition,th einformatio nwa suse dt odetermin eth efollowin g productivityparameters : 1. thegirt hmeasurement sa sa napproximatio no fweight , 2. thecalvin ginterval ,define da sth eperio dbetwee ntw o consecutivebirths , 3. theag ea tweanin go fth ecalf , 4. theinterva lbetwee nweanin gan dth enex tdelivery . Sincegenera lconditio ni slikel yt opla ya nimportan trol ei n farmersdecision st omil kcow s (VanKlin ke tal. , 1994b),th e followingparameter swer eals oanalysed : 5. theinterva lbetwee nth ebirt ho fcalve san dth emomen t thefarmer sstar tmilkin gth emothers , 6. thelengt ho fth emilkin gperiod . Forth ecalculatio no fcalvin ginterval san dth einterval s betweenweanin gan dth enex tdeliver yonl ythos einterval swer e included,i nwhic hth een ddate ,o rth edat eth ene wcal fwa s born,wa sa tleas t9 month slate rtha nth estar to fth esurve y period.Fo rth einterval sfro mweanin gt oth enex tdelivery , thelength so fth emilkin gperio dan dth eage sa tweanin gonl y thoserecord swer eincluded ,referrin gt oanimal sdeliverin g afterth estar to fth esurve yperiod .Fo rth eanalysi so f lengtho fth emilkin gperiod ,weanin gag ean dinterva lbetwee n weaningan dth enex tdeliver yonl yth erecord swer euse do f cowstha tweane dthei rcalves .Thoug hdeath sa sa direc t consequenceo ffluk einfection si ncattl ear erar e (Babalola andSchillhor nva nVeen ,1976) ,th einfluenc eo finfection so n generalhealt han dconditio nma yexer teffect so nmortalit ya s well.Therefor estatistica lanalyse swer ecarrie dou to fth e probabilitytha tanimal sdie do rwer eslaughtered .

138 Calculations.

Forth eevaluatio no fth elactatio ninterval san do fth e girthmeasurements ,analysi so fvarianc ewa sused .I ntabl e1 themodel so fth eanalysi so fvarianc euse dar egiven .Apar t fromth eintervention ,environmenta l factorsa swel la sanima l characteristicswer einclude d inth emodel ;i nth ecas eo f girththi sinclude dse xan dseaso nmeasured ,i nth ecas eo fth e lactationinterval si tinclude dparity ,an di nth ecas eo fth e calving intervalth efat eo fth ecal f (eitherdeat ho r weaning).I nal lcase sth eherd swer eincluded ,an d interactionso fth evariou sfactor swit hth eintervention .

Deathsan dslaughter swer estatisticall yevaluate dusin g LogisticRegressio nanalysi s (Hosmeran dLemeshow ,1989) .Th e probabilitytha ta nanima lwoul ddi eo rb eslaughtere di s expressedb ye^ .Th estatistic so f ß areevaluate db yth e LogisticRegressio nanalysis .Tw oon eyea rperiods ,1s tAugus t 1989til l31s tJul y1990 ,an d1s tAugus t199 0til l31s tJul y 1991,wer eevaluated .I nth eLogisti cRegressio nmodel ,th e interventionwa sincluded ,togethe rwit hsex ,her dan dth e periods (firsto rsecond) .Th eag ea tremova l (or,i nanimal s notleavin gth eherd ,th eag eo n1s tFebruar y 1990(firs t period)an d1s tFebruar y 1991 (secondperiod) )wa sinclude da s randomeffect .Becaus eo fth esampl esiz eth eresult so fth e analysiso fdeath san dslaughter sshoul db eviewe da s indicative.

Results.

Positivefaeca lsample swer efoun donl yi nth efirs tfe w monthso fth eprogramme .Therefore ,n ofurthe ranalysi so fth e faecalsample sha sbee ncarrie dout .

Inth eTriclabendazol egrou pa nestimat eo fth emea ngirt h sizeo f8 7centimeter swa sfoun dfo rth eanimal sbelo wth eag e of1 yea r (500records) ,an do f11 4centimeter sfo rth eanimal s between1 an d2 year so fag e (401records) .N osignifican t differencesi neithe rag egrou pcoul db efoun d forth eeffec t oftreatment .I nth egrou po fanimal sbelo w1 yea ro fag e significanteffect sdi dappea rfo rsex ,8 6centimeter sfo r femalesan d8 8fo rmales .I nbot hag egroup ssignifican t differenceswer efoun dfo rth einfluenc eo fth eher dan dth e season.Whe nth einteraction swer eobserved ,significan t differences,i fany ,coul donl yb esee nalon gth eline so fher d andseason ,an dno ti nth einterventio npar to fth e interaction.

139 Table1 . Theful lmode luse d forth eanalysi so fvarianc eo f girthmeasurement sa sindicator so fweigh tan do f lactationinterval si ninterventio ntrial sinvolvin g flukicidetreatment si ntraditionall ymanage dcattl e inth eWester nProvinc eo fZambia .

Girth Calving Interval Lengtho f Ageo fcal f Interval Interval calving- milking at weaning weaning-next start milking period (weaned delivery (weaned calves) (weaned calves) calves) Intervention: Intervention: Intervention: Intervention: Intervention: Intervention: - Treatment -Treatmen t - Treatment - Treatment - Treatment - Treatment - Control -Contro l -Contro l -Contro l -Contro l -Contro l Sex Parity: Parity: Parity: Parity: Parity: - Female -1 t o> 4 -1 t o> 4 -1 t o> 4 -1 t o> 4 -1 t o> 4 -Mal e Fateo fcalf : Herd Herd Herd Herd Herd -Dea d Intervention* Intervention Intervention Intervention Season -Weane d parity * Herd * parity * parity Intervention Herd Intervention* Intervention Intervention * Herd Intervention* Herd * Herd * Herd Intervention Parity *Seaso n Intervention* fateo fcal f Intervention* Herd

Season: 1=January-March, 2=April-June, 3=July-August, 4=September-December

Inth eRafoxanid egrou psignifican tdifference swer efoun d forsex ,her dan dseaso ni nbot hag egroups .Th eestimate sfo r themea ngirt hsize sfoun dwer e9 0centimeter sfo ranimal s underth eag eo f1 yea r (313records) ,an d11 6fo ranimal s between1 an d2 year so fag e (247records) .I nth eag egrou p between1 an d2 years ,a significan tdifferenc ebetwee n treatmentan dcontro lgrou pwa sfound .Th eestimat efo rth e girthsiz eo ftreate danimal swa s11 7centimeters ,fo rth e controls11 4centimeters .I nth einteraction sth edifferenc e patternso fher dan dseaso ncoul db erecognised .

Hardlyan ysignifican tdifference scoul db eidentifie dfo r thelactatio nintervals .Th eestimate dvalu efo rth ecalvin g intervalwa s65 1day si nth eTriclabendazol egrou p(9 9 records),67 6i nth eRafoxanid egrou p (71records) .N o differencescoul db eidentifie dbetwee nan yo fth evariable si n themodel .I nth einterva lcalving-star tmilkin ga differenc e wasfoun dbetwee nth eherds ,i nth eTriclabendazol egrou p (110 records).Th emea nvalu ewa s9 4days ,an di nth eRafoxanid e group (108records )i twa si nth esam erange .I nth einterva l

140 betweenweanin gan dth enex tdelivery ,wit ha mea nestimate d valueo f31 5day si nth eTriclabendazol egrou p (71records )an d 247i nth eRafoxanid egrou p (47records) ,als odifference swer e foundbetwee nherds .I nth eRafoxanid egrou pa differenc ewa s foundbetwee ntreate d (215days )an duntreate d (278days ) animals.

Infigur e1 th ereason sfo rremova lo fanimal sar egive n forbot htreatmen tschedules .Exchange sbetwee nherd sfo ran y reasonwer eno tinclude d inth efigure .Th elarges tpar to fth e animalsslaughtere d hadt ob eslaughtere dbecaus eo fdiseas eo r weakness.I nal lcase sth enumbe ro fanimal ssol dwa sles stha n theanimal stha tdie dan dwer eslaughtered .N osignifican t differencesi nsale sfigure scoul db efoun dbetwee nth e treatmentan dcontro lanimal si neac hschedule .

Table2 show sth eresult so fth eLogisti cRegressio n analysiso fth eremova lfigures .Fo rillustration ,th enumbe r ofanimal sdyin go fbein gslaughtere d inth etw oon eyea r periodsa sa proportio no fth etota lnumbe ro fanimal spresen t inthes eperiod sar eindicated .N osignifican tdifference swer e found forth eeffec to ftreatmen t inbot hgroups .Significan t effectswer efoun d forher dan dag ei nth eRafoxanid egroup , andfo rher dan dse xi nth eTriclabendazol egroup .

Discussion.

Theschedul eo fth eflukicid etreatment swa sdesigne do n thebasi so fliteratur eo nth einterva lbetwee ninfectio nan d potentialpatenc ythroug heg gsheddin g (Soulsby,1968 ,Armour , 1981).Th eai mo fthi sintensiv eschedul ewa st odetermin e whethera neffec to fradicall y suppressing flukeinfection so n productivity couldb efound .

Notechnica lreaso ncoul db efoun dfo rth efac ttha t hardlyan yfluk eegg shav ebee nfound .Althoug hattempt swer e madet orul eou tth epossibilit yo fmaltreatmen to fth esample s duringtranspor tt oth elaborator ythi scaus ecanno tb e alltogetherexcluded .However ,examinatio no ffaeca lsample s hassevera llimitation s (Armour,1981 ,Troncy ,1989) .Egg sar e expelled intermittently,dependin go nth eevacuatio no fth e gallbladder ,an dthei rnumbe ri sneve ra nindicatio nfo rth e severenesso fth einfection .I nman ycase sn oegg sar efound , orth ecount sar elow ,eve ni nhig hinfectio nlevels .

Asi nman ypart so fAfrica ,an di nman yAfrica nruminan t species (Ogunrinade,1984 ,Schillhor nva nVeen ,1980) ,Fasciol a

141 Figure 1. Number of animals sold, slaughtered and died between the first of August 1989 and the first of August 1991 in herds involved in intervention trials involving flukicide treatments, carried out in a traditional cattle keeping system inth eWester n Province of Zambia.

Triclabendazole Rafoxanicte

0 _ A H >— H Vir t-M 1Ai k>3 «1 "Js Un

12 ^4^B S 13 «K Control Treatment

A= Sale s H= Deat hafte rsickness ,mea tdiscarde d Bs Slaughte rfo rceremon y I= Sudde ndeath ,mea tconsume d C= Slaughte rfo rmoney/mea t J= Sudde ndeath ,mea tdiscarde d D= Slaughte rbecaus eo fsicknes s K= Deat hafte remaciation ,mea t E- Slaughte rbecaus eo facciden t consumed F - Slaughterbecaus eo fweaknes s L= Deat hafte remaciation ,mea t G- Deat hafte rsickness ,mea t discarded consumed/sold M= Death ,no tspecifie d

qiaantica is widespread in the Western Province, as was demonstrated by a high percentage of liver condemnations, positive livers and positive faecal samples (Silangwa, 1972, 1973). The largest egg excretion rates are reported to take place in the early dry season, and the largest number of infected livers between January and June (Jorgensen and Kamukwai, 1977). Treatment against the fluke does however not seem to influence productivity, although even low numbers are suggested to cause loss of production (Babalola and Schillhorn van Veen, 1976, Chick et al., 1980, Hope Cawdry et al., 1977). The reason for this may be, that most of the damage is done by young flukes, that are difficult to approach by any treatment (Mohammed-Ali and Bogan, 1987), that the infection level is moderate, or that the effects of the fluke infestation is masked by low nutritional levels (Owen, 1984, Oakley et al., 1979; both in F. hepatica infections). Contrary to the last remark Simpson et al. (1985) argued that the effects of treatment would be better when nutritional levels are lower. Both Rafoxanide and Triclabendazole are reported to be

142 Table 2. Results of the logistic regression analysis of deaths and emergency slaughters in trials involving flukicide interventions in traditionaly managed cattle from the Western Province, Zambia, calculated over the period 1/8/89 till 31/7/91.

Trielabendazol e Rafoxanide variable No.o f ß s.e. No.o f % ß s.e. animals d./sl.* animals d./sl. in in group group intercept 805 -1.3492 0.3286 563 -2.7427 0.5651 Control 433 8.8 réf. 355 6.7 réf. Treatment 372 10.5 0.1379 0.2543 208 10.6 0.4327 0.3207 Herd1 212 22.6 2.1327? 0.4005 143 13.3 1.5317? 0.5289 Herd2 368 5.7 0.5666° 0.4274 298 7.4 0.7379° 0.5140 Herd3 225 3.6 ref.B 122 4.1 ref.° F 655 7.8 ref.a 457 7.4 réf. M 150 17.3 0.9112° 0.3253 106 11.3 -0.0276 0.4177 PeriodI 419 11.2 réf. 306 9.8 réf. PeriodI I 386 7.8 -0.2310 0.2581 257 6.2 -0.4846 0.3289 Ageou t(pe r 9.6 -0.0012 0.0033 8.2 -.00981 0.0042 montho f age) d./sl.= death san demergenc yslaughter s Valueswit hdifferen t lettersi nth esuperscrip tdiffe rsignificantl y(p<0.05 ) Effectsignifican t(p<0.05 ) effective against young flukes in sheep (Rafoxanide: over 90 % effective against flukes of four weeks and older (Armour and Corba, 1970, Armour et al., 1973), Triclabendazole: over 90 % effective against flukes aged four weeks and older (Boray et al., 1983)); Presidente and Knapp (1972) found a low effectivity of Rafoxanide (58.8 %) against young (6 week old) F. hepatica in cattle.

Knapp et al. (1971) could not identify positive effects of treatment with oxyclozanide on body weight gain and feed efficiency in moderate fluke infections (4 to 10 flukes per liver on average). Kendall and Parfitt (1975) suggested, that alterations in the livers, caused by the infection, influence the rate at which the host rejects the flukes, the reinfection rate as well as the accessibility of the flukes for flukicide drugs. Treatment of old fluke infections is therefore not viable.

The circumstances under which the trials have been carried out may undoubtedly have played a role in the observation, that in general the results obtained in the trials do not show clear advantages in terms of productivity for the treatments involved

143 inth estudies .Logisticall yther ear elimitation st oth esiz e ofth esampl etha tca nb esurveye d ina reliabl emanner ,whe n workingwit hprivatel yowne dherd si na vas trura larea . Conductingtrial sunde rthes ecircumstance sdepend so nth e willingnesst oparticipat eb yfarmer san dpersonel lalike .Fo r thesak eo fclos esupervision ,th egroup so fherd sinvolve dha d tob emanageable .

Notwithstandingth efac ttha tfo rlogisti creason sth e numbero fanimal sinvolve dwa sno tver ylarge ,th esiz eo fth e samplewa sthough tt ob esufficientl y larget oidentif y significantdifference sbetwee ntreate dan duntreate danimal s largertha nthos ebetwee neg .Grazin gManagemen tSystem sa s foundb yVa nKlin ke tal . (1994b),fo rth edependen tvariable s withcontinuou svalues ,suc ha sth elactatio ninterval san dth e girthmeasurements .I fth eformul afo rsampl esiz e determination (Martin,Mee kan dWilleberg ,1986 ,p .45 ,Fleiss , 1986,p .369 )i sapplie dt oeg .th edifference sbetwee nth e girthsi nth eag egrou pove rth eag eo ftw oyear si nGM S1 an d GMS3 (VanKlin ke tal. , 1994b),a differenc eo froughl y7 cm . ingirth ,an dth eexpecte d standarderro ri sestimate da t around3 cm. ,les stha n2 0animal si nbot htreatmen tgrou pan d controlgrou pshoul db esufficien tt oidentif ythi sdifference .

Theenvironmenta lcircumstance sno texplaine db yth e modelsuse dmay ,however ,stil lb esubstantial ,influencin gth e reliabilityo fth eresults .Whethe rthi swoul db eo f importance forth epractica l implicationso fth eresult so fth etria l dependsentirel yo nth eeconomi cvalu eo fexistin gdifferences ; thecost-benefi trelatio nbetwee nth emaximu mamoun to f investmentan dth eminimu mamoun to fimprovemen to fproductiv e performancerequired .Thi seconomi cvalidatio nha sno tbee n carriedou ti nth eframewor ko fthi strial .

Thesampl esiz efo rth edeterminatio no fth einfluenc eo f treatmento ndeath san dslaughter sprove dt ob efa rfro m adequate.Th efac ttha tn oeffect so ftreatmen tcoul db e measured,shoul d likelyentirel yb econtribute dt othis .Th e samplesiz ewoul dhav et ob eincreased ,o rth esurve yprolonge d substantiallyt omee tth erequirement sdemande db yth eformula . Bothth elogisti cdifficultie si nth efiel dmentione dearlier , andth efac ttha tth esurvey sar ecarrie dou ti na developmen t project,tha tcount sth eus eo fresults ,rathe rtha nresearc h assuc hamon git sobjectives ,limit sth epossibilitie st o attainthis .Th eresult so fth eanalysi so fdeath san d slaughtersobtaine d inthi sstud yshoul db eviewe dtogethe r withth eresult so fgirt han dlactatio nintervals .I nth e

144 followingdiscussio nth eresult so fal lanalyse swil lb e reviewed,a sobtaine d inthi sstudy .Conclusion swil lb edraw n mainlyo nth ebasi so fth eresult so fth econtinuou sdependan t variables,bearin gth eremark smad esofa ri nmind .

Theweigh to fanimal si nth efirs ttw oyear so fag edoe s notsee mt ob einfluence dsignificantl yb yth etreatment s given,excep ti non eyea rol danimal si nth eRafoxanid eherds . Thegirt hmeasurement so ftreate danimal si nthi sgrou par e slightlybigger .Th eeffect so fsex ,her do rseaso nar ei nmos t casessignificant .Th einfluenc eo fth eenvironmen tan d managementwoul dsee mt ob eo fgreate rimportance .Va nKlin ke t al. (1994a-d)als ofoun dinfluence so fth eenvironmen tan d management.

Thepresen tinformatio ndoe sno tallo wconclusion sa st o theeconomi crelevanc eo fth eeffec tsee ni nth eon et otw o yearol danimal si nth eRafoxanid egroup .I nth etraditiona l systemo fth eWester nProvince ,weigh ti so flimite ddirec t importance.Th emanagemen t isno taime da tproducin gyoun g animalsfo rsale .Th eimportanc eo fimprove dweigh tthroug h treatment liesprobabl yonl yi nth efac ttha tthes eanimal sma y matureearlie ran dcontribut et oth eincreas eo fth eher da ta n earlierstage .

Inth elactatio ninterval sver yfe wsignifican teffect s couldb efound .Th etreatment sdi dno thav ean yinfluenc eo n thecalvin g interval,th einterva lbetwee ncalvin gan dmilking , thelengt ho fth eperio da co wi smilke dan dth eag ea twhic h thecal f isweaned .Th efac ttha tth einterva lbetwee nweanin g ofth ecal fan dth enex tdeliver ywa sshorte ri nth egrou p treatedwit hrafoxanid etha ni nth econtro lgroup ,ma yb ea n indication,tha tth ebod yconditio no fth etreate danimal s allowsthe mt ocontinu esucklin g forsom etim ewhil ealread y beingpregnant .I nth econtro lgroup ,an di nth eentir e Triclabendazolegroup ,th ecow ssee mt ohav eweane dthei r calvesbefor econceiving .

Infigur e1 a nattemp twa smad et odifferentiat ebetwee n severalreason sfo rslaughte ro rdeath ,t oasses swhethe ra differencei nthi spatter ncoul db esee nbetwee ntreate dan d untreatedanimals .Th eonl yconclusio ntha tca npossibl yb e drawnfro mth eresult sis ,tha tth eproportio no fanimal ssol d doesno tsho wa differenc eclearl y indicatingth eadvantag eo f anyo fth etreatments .I ftreatment swoul dhav eha da clea r effect,mor eanimal swoul dprobabl yb eavailabl efo rsale ,bu t thefarmer swoul dprobabl ydecid et okee pexactl ythes eanimal s

145 inth eherd .Th eslaughter swer eevaluate dtogethe rwit hth e deathsi nthi spaper ,becaus efigur e1 show stha ti nmos to f thecase sanimal swer eslaughtere dbecaus eo femergencies ; sickness,ol dage ,accident so rweakness .

Innon eo fth etrial sth eeffect so fth etreatment so nth e probabilityo fmortalit yan dslaughte rwa ssignifican t (table 2). Significanteffect scoul donl yb efoun dfo rherd ,i.e .th e effecto fth emanagement ,an dag ea tremova l (Ageout) . Itma y beexpected ,tha t improvement inperformanc eo fth eher dma yb e attainedprimaril ythroug himprovemen to fth eperformanc eo f theher dmanager .

Forth esituatio ni nth eWester nProvinc eth eresult so f thepresen ttria ld ono tjustif yth erecommendatio no fregula r treatmentschedules .Th eresult so fth elactatio ninterval san d girthmeasurement sanalyse sd ono tsho wclea radvantage so f treatment.I ti sno tpossibl et odra windependan tconclusion s onth eeffect so ndeath san dslaughters ,bu ti tma yb eassume d thatdifference sher ear eno tlikel yt ob emor eoutspoke ntha n inth eanalyse so fth econtinuou svariables .A sMiche l (1972) pointedou tfo rtreatment sagains t intestinalnematodes , treatmentshoul db eeconomicall y justifiable,i.e .th egai n shouldb ebigge rtha nth enecessar y investment.I na traditional livestockmanagemen t system,i nwhic hhardl yan yo r noexterna linput stak eplace ,th ebenefit sshoul db e relativelydirec tan deasil ymeasurable .Recommendation sshoul d atleas tb ebase do nevaluatio no fth eeffect so ftreatments , alsoi neconomica lsence .

Preventingheav yinfection swit hliverfluke scoul d probablybes tb eachieve db yadjustin gth egrazin gpractices . Sincecommuna lgrazin gi spractice dthroughou tth eprovince ,i t isunlikel ytha tinfectio nca nb eprevente dentirely .I tma yb e possiblet opreven tth eoccurrenc eo facut eliverfluk edisease , asdoe soccu ri nsmal lnumber si ncertai nperiod so fth eyear , bycareful lday-to-da yplannin go fth egrazin gare aan d careful1us eo fwaterin gpoints .Th eus eo fman-mad ewaterpond s islikel yt ob epreferabl eabov ewaterin ganimal si nox-bow s andcreek stha tar eperiodicall y suppliedwit hwate rb yth e rivers.Especiall ywhil edryin gup ,thes erive rbranche s containlarg enumber so fth esnai lLvmne anatalensis .th e vectoro fFasciol agigantic a (ADCP,unpublishe ddata ,1986) . Thereappear st ob ea greate rrol efo ra veterinar y extensionisttha nfo ra veterinar ytechnician .Furthe rstud y mayhav et ob edirecte dmor etoward sth edevelopmen to fthi s typeo fextensio nmessage stha ntoward sdevelopin g

146 recommendations on routinely using drugs for liverfluke control•

On the basis of the results obtained it is difficult to answer the question whether the herd monitoring programme is suitable for use in clinical field trials. The fact that the differences that could be identified in the present surveys are fairly comparable with those found in productivity surveys carried out earlier would suggest, that the data collection in this manner is sufficiently accurate, and that adaptations in the trial design would improve the output of the trials.

Acknowledgements. The authors wish to thank the Director of the Department of Veterinary and Tsetse Control Services of the Republic of Zambia for his permission to publish this paper. Dr. E. Wiersma is acknowledged for his contributions to the trials. Dr. B.H.M. van Munster is greatly acknowledged for her useful comments on the manuscript.

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15. Klink,E.G.M ,van , J.J.F.M.Corten , S.H. Wiersma and G.C.Bbal o (1994b). Herd monitoring intraditiona l cattle husbandry of Western Province, Zambia, III: reproductive performance, lactation intervals and growth,(submitted) . 16. Klink, E.G.M,van , J.J.F.M.Corten , K. Frankena, E.M. Chiposa (1994c). Herd monitoring in traditional cattle husbandry of Western Province, Zambia, II: survival rateso f calves,mortalit y and slaughter figures,an d sales figures, (submitted).

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148 27. Schillhornva nVeen ,T.W . (1980). Fascioliasis (Fasciolagigantica )i nWes t Africa:a review.Vet .Bull. ,50 ,529-533 . 28. Silangwa ,S.M .(1972) .Epizootiolog yo fBovin e Fascioliasisan d theProblem so f Control inth eMajo r FloodPlai nRegio no fZambia .Proc .197 2Eas tAfrica nMed . Res.Counci l Sei.Conf .Chapt .8 ,Pape r4 . 29. Silangwa,S.M . (1973). Incidenceo f Liver Flukes (Fasciola gigantica)i nBarots e Cattle,Zambia .Bul l Epizoot.Dis .o fAfrica ,21 ,11-17 . 30. Simpson, J.R., C.H.Courtne yan d J.K.Sheare r (1985).Economi cAnalysi so f Controlling Liver Flukes.Agri-Practic e6 , 20-24. 31. Soulsby, E.J.L. (1968).Helminths ,Arthropode san d Protozoa ofDomesticate d Animals (Moennig).Bal iere ,Tindal l and Cassell,London . 32. Troncy, P.M. (1989).Helminth so f livestock and poultry intropica l Africa. Foreword. In:Shah-Fisher ,M .an dR .Sa y (Transi.).Manua l of tropical veterinary parasitology (Engl.Ed.) . C.A.B. International,UK .

(submitted for publication.)

149 4.2.Th eus eo fa her dmonitorin gprogramm e forth eevaluatio n ofth einfluenc eo fantiparasiti ctreatment so nth e productivityo ftraditionall ymanage dcattl ei nth eWester n Provinceo fZambi a II:intervention swit hAvermectin ean d Thiabendazolean da combinatio no fRafoxanid ean d Thiabendazole.

E.G.M.va nKlink 1,L .Schoonman 1,6.M . Bbalo1,an dI .Muhongo 1.

Introduction.

Intestinalnematode san dliverfluke si nruminant sar e oftenpresen twithou tcausin gapparen tdisease .Infection sd o howeverexer tpressur eo nth egenera lconditio no fanimal s (Abdalla,1989 ,Michel ,1972) .Eve nwhe npresen ta tmoderat e levelso finfection ,th epressur eo nth econdition ,cause db y internalparasites ,depresse sth eproductivit y invariou sway s (Maingian dGichigi ,1992) .Growt h (Chiejinaan dEmehelu ,1986 ) andmil kproductio n (Bargeran dGibbs ,1981 )ma yb eaffected , andth ecapabilit yt ocompensat eweigh tlos s (Kaufmannan d Pfister,1990 )ma yb eimpaired .Severa ltreatmen t schedules havebee npropose d fortraditionall ymanage d livestock (Bianchinan dHoner ,1987 ,Chiejin aan dEmehelu ,1986 ,Conno r etal. ,1990 ,Majo ke tal. , 1993). Ifan yschedul ei st ob e adopted iti snecessar yt oevaluat eth eeffect so ftreatmen to n theproductiv eperformanc eo fth eanimal sfo rwhic h iti s intended,particularl ytakin g intoacoun tth ebenefi ti n economicterm stha ti st ob egained .

Thispape rdescribe sth eevaluatio no fth eus eo fa her d monitoringprogramm etha tha sbee nuse dearlie rfo rth e evaluationo fgenera lproductivit ytrait s (VanKlin ke tal. , 1994c)i nth eWester nProvinc eo fZambi a (DeRooi jan dWood , 1990), forth eassessmen to fth eeffec to ftreatment sagains t gastro-intestinalparasite san da combine dtreatmen tagains t gastro-intestinalparasite san dliverfluke s (Fasciola giqantica)o nproductivity .Apar tfro massessin gth eeffect so f treatmento nproductivit yth equestio nwa spu tforwar dwhethe r theprogramm ewa ssuitabl efo rth epurpose ,give nth elogisti c difficultieso fth erura lare ai nwhic hth estud ywa scarrie d out.

^Department of Veterinary and Tsetse Control Services,Wester nProvince ,Zambia .

151 Materialan dmethods .

Areaan dclimate .

Theare aan dth eclimat ei nwhic hth etrial swer ecarrie d outwer edescribe db yVa nKlin ke tal .(1994c) .Herd sbase di n GrazingManagemen tSystem s (GMS)1 ,3 an d4 wer einvolve di n thetrial sinvolvin gtreatmen tagains tgastro-intestina l parasites,an dherd sfro mGrazin gManagemen tSystem s1 an d3 i n thecombine dtreatment .I nGM S1 th eanimal sar emaintaine d undertranshuman tmanagement ,whic hmean stha tthe yar ebase d inth efloodplain so fth eZambez irive rfo rth elarge rpar to f theyear ,an dmov eou to fth efloodplain sove rdistance so f1 0 to4 0kilometer swhe nth ewaterleve lo fth erive rrises .Th e herdsi nGM S3 an d4 ar esedentary ,whic hmean stha tthe yd o notmov eove rconsiderabl edistances .I nGM S3 th eanimal sar e mainlymaintaine d inuplan drive rvalley san dth ehig hlan d surroundingth efloodplain .Th eare ao fGM S4 i sconsiderabl y drier,an dfe wuplan driver sar epresent .Th eanimal sdepen d largelyo nman-mad ewell sfo rthei rwatersupply .

Experimentalherd san dtreatmen tschedule .

Thenumbe ro fherd sinvolve d ineac htrial ,th etreatmen t schedulean dth etyp eo fanimal sinvolve d inth eevaluatio ni s giveni ntabl e1 .Th etota lnumbe ro fherd sinvolve dha dt ob e keptlimite dbecaus eo fth erequire d levelo fsupervisio nan d forlogisti creasons .I neac hher da treatmen tan da contro l groupwa sformed ,approximatel yequa li nsiz ean dag e composition,b yrankin gth eanimal saccordin gt oage ,withi n thesexes ,an dalternatel yassignin gthe mt oeithe rth econtro l groupo rth etreatmen tgroup .Th edosag eo fth etreatment swa s determinedo nth ebasi so fweigh tassessment susin gth egirt h measurementsan da girth-weigh tconversio ntabl edevelope di n cattlei nth eWester nProvinc e (Corten,1988) .

Allanimal sbelo wth eag eo ftw oyear swer einclude di n thetrial sinvolvin gtreatmen tagains tgastro-intestina l parasites,an dal lanimal sbelo wth eag eo ftw oyear san dal l femaleanimal si nth ecombine dtreatmen ttrial .A tth estar to f thesurve yaroun d 180animal sbelo wth eag eo f2 year swer e present inth eAvermectine 2group ,equall ydevide dove r treatmentan dcontrol ,aroun d9 0wer epresen ti nth e

Ivomec;Merck ,Sharp ean dDome ,Haarlem ,Th e Netherlands.

152 Table 1. Treatment schedules, anthelmintic and flukicide agents used and number of herds per treatment type of an intervention trial into the effect of treatment on productive performance in traditionally managed cattle in the Western Province, Zambia. In each of the herd the animals of the age group indicated were devided over a treatment and a control group.

Thiabendazole Avermectine Rafoxanidean d Thiabendazole Numbero fherd si n 5 6 3 trial Treatmentschedul e 6/year,dr y 6/year,dr yseason : 4/yearRafoxanide , season: interval 3 interval 3months , 6/year months,we t wet season: Thiabendazole season: interval6 interval6 weeks weeks Typeo fanimal s All animals< 2 All animals< 2 All animals< 2 involvedi n years years years,al lfemale s analysis

Thiabendazole3 trial herds. Around 270 animals below the age of two years and female animals were present in the combined treatment trial herds. The total numbers of animals having been involved during the complete survey period for each group were 149 treated and 195 control animals in the Avermectine trial, 73 treated and 103 control animals in the Thiabendazole trial, and 164 treated and 223 control animals in the combined trial, consisting of treatments with Rafoxanide4 and Thiabendazole.

The automated herd monitoring system described by Van Klink et al. (1994c) was used to process the information of the monitoring of the herds for a period of two and a half years. The monitoring was carried out through two-weekly visits by Veterinary Assistants and three-monthly visits by District Veterinary Officers. The treatments started in February 1989, and the records taken in the period 1st of August 1989 till 31st of July 1991 were included in the analysis.

Thibenzole; Merck, Sharpe and Dome, Haarlem, The Netherlands.

Ranide; Merck, Sharpe and Dome, Haarlem, The Netherlands.

153 Atever ythree-monthl yvisi t5 individua lfaeca lsample s fromanimal si nth etreatmen tgrou pan d5 individua lfaeca l samplesfro manimal si nth econtro lgrou pwer etaken .Th e sampleswer epurposivel ytake nfro mth efirs t5 animal si neac h grouptha tpasse dthroug hth ecrus ho fth eholdin gfacility . Thesample swer echecke dfo rth epresenc eo fhelmint heggs ,i n particularstrongylus-typ eeggs ,usin ga flotatio nmetho dwit h sodium-chloride (Troncy,1989) .Al lsample scontainin ga tleas t oneeg gwer eterme dpositive .Durin gthes evisit sth e treatmentso fth eanimal swer edon ean dgirt hmeasurement swer e taken.

Forth eanalysi so fth eproductivit yth efollowin g parameterswer eused :th egirth ,a sa nindicato ro fweigh t (Nicholsonan dSayers ,1987) ,an ddeath san dslaughters ,i nth e trialsinvolvin gtreatmen tagains tgastro-intestina lparasites . Sincei nth ecombine dtreatments ,adul tcow sreceive da flukicidetreatment ,parameter srelate dt oreproductio nan d lactationwer eals oincluded .Apar tfro mgirth ,an ddeath san d slaughters,i nthes eherd sth ecalvin g interval,interva l betweencalvin gan dth emomen tcow sar ebein gmilke d forth e firsttime ,th elengt ho fth emilkin gperiod ,th eag ea t weaningo fth ecalf ,an dth einterva lbetwee nweanin gan dth e nextdeliver ya sa measur eo freproductiv eperformanc ean d generalcondition ,wer eals oevaluated .Fo revaluatio no f calving intervalonl ythos ewer eincluded ,o fwhic hth esecon d calvingdat ewa sa tleas t9 month safte rth estar to fth e survey.Fo ral lothe rinterval sth erecord swer eused ,relate d todeliverie stakin gplac eafte rth estar to fth esurvey .Fo r evaluationo fLengt ho fmilkin gperiod ,ag ea tweanin gan d intervalbetwee nweanin gan dnex tdeliver yth erecord swer e usedo fcow stha tweane dthei rcalves .Thes eanalyse sonl ybea r relationt oth eflukicid etreatment ,sinc eth eduratio no fth e surveywa sto oshor tt oevaluat elon gter meffect so ftreatmen t againstgastro-intestina lparasite sgive ni nth efirs ttw o yearso flife .

Calculations.

Duet oth enecessaril y smallnumbe ro fherds ,i twa sno t possiblet oachiev estatisticall y reliablesampl esize sfo r parametersmeasure d asproportions ,e.g .death san dslaughters . Forparameter smeasure da smeans ,e.g .th ecalvin ginterval , thesampl esize swer edeeme dt ob esufficientl y large.Th e resultso fth eevaluatio no fdeath san dslaughter sshoul d thereforeb eviewe da sindicative .

154 Themodel so fth eanalysi so fvarianc euse dfo rth e evaluationo fgirt hmeasurement san dlactatio ninterval sgive n byVa nKlin ke tal .(1994a )fo rth eevaluatio no fflukicid e interventiontrial swer euse di nthi sstud ya swell .Th emodel s consistedo fth eintervention ,i.e .treatmen to rcontrol ,an d herd.I nth eanalysi so fth egirth ,sex ,seaso nan d interactionsbetwee nth einterventio nan dth eothe rfactor s mentionedwer eincluded .I nth eanalysi so fth elactatio n intervalsth eparit ywa sincluded ,an di nth ecas eo fth e calving intervalsals oth efat eo fth ecalf ,i.e .whethe rth e calfha ddie do rwa sweaned .Als oi nthi scas einteraction s betweenth evariou sfactor swer eused .

Forth estatistica levaluatio no fdeath san dslaughters , LogisticRegressio nanalysi swa suse d (Hosmeran dLemeshow , 1989).Death san dslaughter swer eevaluate dove rtw oon eyea r periods,coverin gth etota llengt ho fth esurve yperiod .Th e LogisticRegressio ncalculate sth eOdd sRati o (OR)o fa neven t happeningunde rdefine dcircumstance sa scompare dt oa referencesituation .I texpresse sth eO Ra sa powe ro fth e numberc ,an dstatisticall yevaluate sth epower , ß. Ifth eO R is1 ,i.e . ß is0 ,ther ei sn odifferenc ebetwee nth etw o situations.Th emor eth eO Rdeviate sfro m1 ,th emor eth etw o situationsdiffer .I nth emode luse d forevaluatio no fdeath s andslaughters ,th emode lincluded ,apar tfro mth e intervention,als oth eherd ,th ese xan dth eperiod .Th eag ea t removalwa sinclude da srando meffect .Fo ranimal sno tremove d theag ewa sdefine da sth eag ei nday sa ta dat e6 month safte r thestar to feac hperiod .

Results.

Infigur e1 th epercentage so fth efaeca lsample sfoun d positivefo rhelmint hegg si sshow nfo rth ecalenda rmonth sth e sampleswer etaken .Th ehighes tpercentag eo fpositive swer e founddurin gth ewe tseason ,betwee nNovembe ran dApril . Generallyth epercentage spositiv esample swer ehighes ti nth e controlgroups .

Onlyi nth eAvermeetin egrou pth eestimate so fth egirt h sizeswer esignificantl ydifferen tbetwee ntreate dan dcontro l animals,bot hi nth egrou po fanimal so fles stha non eyea ro f age (treatedanimals :9 4cm. ,controls :9 1cm.) , andi nth e groupo fanimal sbetwee non ean dtw oyear so fag e (treated animals12 1cm. ,controls :11 9 cm.).Neithe r inth e Thiabendazolegroup ,no ri nth ecombine dtreatmen tgrou p significantdifference sbetwee ntreate dan duntreate danimal s

155 Figure1 . Percentageso ffaeca lsample sfoun dpositiv efo r helminthegg sfoun da tvariou smoment so fth eyea ri n herdsinvolve d ininterventio ntrial sconsistin go f treatmentagains tgastro-intestina lparasite s (Aan d B), ora combine danthelminti can dflukicid e treatment (C),i nth eWester nProvinc eo fZambia .

B Avermectine intervention Thiabendazole intervention

TtMtmnt EH3 Control 9 TtMtmnt HI Control

• 10 n is • 10 11 IS

Rafoxanide/thiabendazole intervention Traaarant ËP Control

couldb efound .Significan tdifference sdi dexis ti nal lgroup s betweenseasons ;I nth efirs tsi xmonth so fth ecalenda ryea r thegirt hmeasurement swer egenerall y significantlyhighe rtha n inth esecon dsi xmonth so fth eyear .I nth egrou po fanimal s belowth eag eo fon eyea ra swel la si nth egrou po fanimal s betweenon ean dtw oyear si nth eThiabendazol etria l significantdifference swer esee nbetwee nherds .I nth e combinedtreatmen tgrou pa significan tdifferenc ebetwee nherd s wasonl ysee ni nth eanimal sbetwee non ean dtw oyear so fage .

Innon eo fth elactatio ninterval sevaluate d inth e combinedtreatmen ttrial ,significan tdifference si nlengt h

156 Figure2 . Numbero fanimal ssold ,slaughtere d anddie dbetwee n thefirs to fAugus t198 9an dth efirs to fAugus t199 1 inherd sinvolve d ininterventio ntrial sconsistin g oftreatmen tagains tgastro-intestina lparasite s( A and B), ora combine d anthelmintican dflukicid e treatment (C),i nth eWester nProvinc eo fZambia .

B Avermectine Thiabendazole

Control Control Treatment

Rafoxanide/thiabendazol e A = Sales B = Slaughter for ceremony C = Slaughter for money/meat D - Slaughter because of sickness E = Slaughter because of accident F = Slaughter because of weakness G = Death after sickness, meat consumed/sold H = Death after sickness, meat discarded I = Sudden death, meat consumed J = Sudden death, meat discarded Control Treatment

could be found between treated and non-treated animals. The only significant differences that could be identified were found between herds, for the calving interval and the interval between calving and the start of milking.

The removals of animals from the herds because of deaths, slaughters and sales are given in figure 2. Practically all slaughters took place because of disease, weakness or accident. Since these slaughters can be considered as emergency slaughters, they are evaluated together with deaths. Although the proportion of animals sold seems slightly bigger in all treatment groups, differences are not significant.

157 m m rv o> CM m M a! LTI rv 00 in IO o Kl ai •O O •O 00 w— o > M IO Kl IO o o O o o o O o o c "O •o o Si >0 ^_ •ri a> «M o CD ÏL s •P 01 Kl CM IO IO >o» id «•- ro H- IO o H- M- o m "o «a. **-ai 01 CM o 01 »* 01 •-t Kl c o C C o U o o Oul 3 n i 1 CM • 1 •p U *~ si rH id Ü 0) o IO CM IO 1». » IO o o3 > U ID »< v. Kl O •o CM 03 oo oo ut T) » •o CM r-l w 4-» *" 10 (d c» •H "8 >1 •P a U € 41 ï c (d T> C _ 01 M c 0> (0 h X :O i- * o O) ai H- CM oo sr 2p in CM CM S 01 |v h- m 2 IO O o CK S u et o c o Kl CM CM CM . ._ in o 00 CK 00 >* fv >» C 0 ai >o r«. m r^ IV O id ^CM* o fc Nt -o O O » u CO «~ >* «— O ^r* o IO V» o m o. «^ O «^ «^ r —' o o o X3 •p c INI m IO m 00 id u m g 3 o> CM CM o ai m IO O 1 CM •P H- oo IO M- o> O ai 3 ««- 1• IÇ »•- «a. ai 01 o ai ai a CM c O CM i. o c >» •o • c o i • o o ai «— *~ 1 «H S o ai ^ |v- m 00 o> rv m iv -O Kl o a> si »t -v -H •P o o ró «J <à CK >* -o' m CM o •o a> •d CM CM CM CM CO >i *~ *~ *~ "~ "~ rH 0a (0 ai m «uH "o § icd N 01 a c _ c •o 0 u Ü •H 01 a Ol m £ •O in •o CM o O CM •O m • f o c w— o CM IO >s» ^1- O o> O o m rH r- z •— ^(M •o C^M~ 01 01 C* . "~ "~ "~ *~ '" M rH 0» +J fv , CM ,_ ,_ »* o IO m IV CM m O •O m s» ie IO Kl u •d *H^ M «O * IO o o o o o IO Kl o u m «- O o O o •uH rH •p •rci rH 55 •ri a a es m O IL in l^1 _ m Kl N* •ri 01 +J g m t o CM Si m CM CK O» r-t 00 c» IO oo m 00 O o H- m N» •*>» H- «•- CM «c- O n) O» «a. ai * • 01 01 ai »» o «•• i-t •r| 00 «» C o • CM CM CM• CM <- c. o c_ O o ri 1 ' • 0) -P 00 fe £ ^ _J •P C rH ta tv » o Kl O IT- rv •* *•; ^ 0 • «H •ri C» o m IO CM Iv o TJ oo «— >* «^ <* «— 0 •P o "~ *~ *~ «— *~ *~ *~ *" C •ri CO H a ai -^ O) •P > 01 01 Ol ^H u Ol C 1 3 01 'E cd a a 0) •p 01 *u^ 3 PH H- O ai Si O t- •cH •p i •p « O) X a> • 00 in m CO IO ^J- m O -O K-oI -o m ^00 >» IV ^ CM CM Kol ai > o c >CM» •r- ^* ^CM~ CM CM »C—M • < z •— «* s *~ >* c CM +* •o ai «-» c t.^ Mi.^ H- ai a) V O c ai u O CM IO m o ai 3 01 •H U *-< *~ >* w O f ac_i a •o •o •o •o "O 'D ai L. *J ^N cn XI c_ 4-» *-» ai c_ C- C_ b- C_ !_ 2c 2c 01 « C 01 01 •d "~ u r- 3C ac X se z z i^ z a. a. < w g CO (legend Table 2.)

JA *d./sl .=death san demergenc yslaughter s Valueswit hdifferen tletter si nth esuperscrip tdiffe rsignificantl y(p<0.05 )

The results of the logistic regression analysis of deaths and slaughters are given intabl e 2.Th epercentag e of all animals present inth e two one year periods evaluated, that died or were slaughtered, is indicated as illustration.A t a .95 confidence level,significan t differences were only seen between herds.Th e herd effect could not be identified in the Thiabendazole group at this confidence level.A t a confidence level of .90,bot h treatment and herd showed significant effects inth e Thiabendazole group on deaths and slaughters. The percentage of the animals that died orwer e slaughtered in the control herds inthi s trialwa s twice as high as in the control groups inth e other trials.Treatmen t effects were not found inth e other trials,a t this confidence level.

Discussion.

The patterns of the faecal samples found positive for helminth eggs arewel l comparable with patterns found earlier inth eWester n Province (Bongers,1987 ,unpublishe d data) and with egg shedding patterns inneighbourin g countrieswit h a comparable climate (Malanet al., 1982). Both egg shedding and worm burdens are highest inth ewe t season (Pandey, 1990). The percentage positives were slightly, though not significantly lower inth e treatment groups.Treatment has reduced the proportion of animals that deposit eggs, while not completely preventing reinfection, allowing forth e development of resistance. The levels of the EPG'swer e always very low. They were therefore not included inth e figures.Th e low levels of the EPG'sma y mean that helminthiasis isno t a severe problem. Eysker et al. (1990)relat e highwor m burdens to overstocking, and Jeanes and Baars (1990)argue d that the carrying capacity of theWester n Province was not reached by far.However , EPG's do not always seem to be an indication of the seriousness of the infection (Parent and Samb, 1984). Though the carrying capacity of the province as awhol e has not been reached yet, it isquit e possible that locally and periodically overgrazing does occur.

The sample sizeswer e considered tob e sufficient to determine differences between valueso f the lactation intervals and the girth.Th e sample sizes proved however to be by no

159 meansbi genoug ht oevaluat ereliabl yth eresult so fth e analysiso fdeath san dslaughters .Whethe reffect so ftreatmen t doo rd ono texis tca nno tb econclude d fromth eresult so fth e LogisticRegressio nalone .Prolongatio no fth esurveys ,o r repeatingth estud ywit ha considerabl y largernumbe ro f experimentalunit scoul dimprov eth eusefulnes so fthi s statistic.I tma yhoweve rb elogisticall ydifficul tt omaintai n theoperatio no fa surve yo fth erequire dsize ,dependin go n thecooperatio no findividua l farmersan do nth ereliabl ean d uniformapproac hb ya large rnumbe ro fpersone l involved,a s wasalread yconclude db yVa nKlin ke tal .(1994d) .

Thefact ,tha ta ta confidenc eleve lo f .90th etreatmen t withthiabendazol eprove dt oreduc eth eOdd sRati ofo rdeat h andslaughte rsignificantly ,i sundoubtedl yrelate dt oth ehig h percentageo fanimal stha tdie do rwer eslaughtere d inth e controlgroup .I ti spossibl etha ti nsom eo fth eherd si nthi s triala clinica lproble mo fgastro-intestina lparasitis m existed.

VanKlin ke tal .(1994a )foun dsignifican teffect so n girthsize so fseasona linfluence san do finfluence so fth e GrazingManagemen tSyste man dth esex .Th eeffect so fse xan d seasonfoun di nth epresen tsurve yar ecomparabl ewit hthos eb y VanKlin ke tal . (1994a).Whethe ro rno tth esignifican t differencebetwee ntreate dan dnon-treate d animalsfoun d inth e Avermectinetria lwoul dmak eregula rAvermectin etreatment s viabledepend so nth eeconomi cvalidatio no fth eeffec tan dth e intensityo fth eschedul echosen .Paren tan dSam b (1984)foun d ahighl ysignifican teffec to fAvermectine .Paren tan d Alogninouwa (1984)foun da significan tdifferenc ei nth e averageweigh to fcalve sa tbirt han dafte r8 0days ,whe nth e motherswer etreate d inth efiel dwit hAvermectin ei nth elas t monthso fgestatio nan ddurin gth edr yseason .

Inconsiderin gth efac ttha tneve ra ninfluenc eo fth e treatmentscoul db efound ,i tma yb eargued ,tha tth e unexplained influences,no tinclude d inth emodels ,ma ystil l havebee no fgrea timportance .A swa sdiscussed ,th esampl e sizema yhav ebee nto osmal li npractice ,although ,a s indicated,th esiz eseeme dtheoreticall ysufficient . Specifically apositiv einfluenc eo nth ecalvin g intervalwoul d havebee na useful leffect ;improvemen to fth ereproductiv e performancewoul di ntraditiona lsystem sb eo fgreate r significancetha nimprovemen to fgrowth .Weigh to rgirt hma yb e theparamete ro fchoic et oasse sth epresenc eo fa neffect ,bu t itwoul dno tb esufficien tt ous ei ta sdirec tmeasuremen to f

160 theeconomi cbenefi t (income)o ftreatmen tunde rcircumstance s oftraditiona l livestockmanagement .Traditiona l farmersar e rarely,i fever ,aime da tproducin gread yt oslaughte ranimal s fora specifi cmarket .Normall ythei rmai nai mwoul db et o increaseth eher dsize ,o rrather ,reducin gth erisk so f decreasingthei rnumbers .Growt ho fanimal stake splac ewithou t anyinput ;i fanimal shav et ob esold ,normall yadult ,eve n old,animal swil lb echosen .Improvemen to fgrowt hma yb eo f indirectimportanc ethroug hdecreasin gth ematurin gage , resulting inearl yparticipatio no fth eanimal si n reproduction.Improvemen to freproductiv eperformanc ei s directlymeasurabl ean dwoul db ea nargumen tfo rfurthe rstud y intoth eeconomi cviabilit yo fregula rtreatment .

Infigur e2 informatio nrelate dt osales ,slaughter san d deathsha sbee nbrough ttogethe rfo reac ho fth etreatmen tan d controlgroup st oillustrat eth ereason sfo rremova li nsom e detail.A swa sals oshow nb yVa nKlin ke tal . (1994b), practically allanimal sar eslaughtere dbecaus eo femergencies , andwer etherefor eevaluate dtogethe rwit hdeaths .N oinfluenc e oftreatmen to nth erelativ efrequencie so fdeat ho rslaughte r forreason so fsickness ,emaciatio no rweaknes so ro fsudde n deathcoul db eidentified .

Aswa salread ystated ,i ti sdifficul tt odra wconclusion s fromth eresult so fth emortalit yanalysi so nit sown ,i nterm s ofth eeffec to ftreatment .Particularl yth einfluenc eo fth e herdma yb eimportant ,sinc ei tsignifie sth einfluenc eo fth e herdmanagemen to nth eperformanc eo fth eanimals .Thi smean s thatmos tlikel yth ebigges tprogres si nth eperformanc eca nb e found inimprovin gth eanima lhusbandr y andher dmanagemen t practices.

Treatment schedulesagains tintestina lnematode sar eofte n recommended onth ebasi so fth eeffectivit yo fth edru gagains t theparasite s (Bianchinan dHoner ,1987 ,Grabe ran dPerrotin , 1983, Maingian dGichigi ,1992 ,Majo ke tal. , 1993).Th ecost - effectivenesso ftreatment si sles softe nmentione d (Chiejina andEmehelu ,1986 ,Muensterman nan dTome ,1989) .Th ecost - effectivenesso ftreatment sis ,however ,o fprim eimportanc e (Michel,1972) .Th eimprovemen to fperformanc eshoul dals ob e directlymeasurable ,particularl y inlow-inpu ttraditiona l management systems.I nth emateria luse dfo rth etrial scarrie d outi nth eWester nProvinc en ojustificatio nfo rregula r treatmentscoul db efound .Recommendation s shouldtherefor eb e restrictedt otreatmen to fclinica ldiseas esuspecte do fbein g causedb yintestina lparasites .Furthe rresearc hma yb eaime d

161 at assessing whether treatments could be of use in relieving the adverse effects on productivity of local and periodical overstocking. Here also, the economic aspects of treatment are of major importance.

As was also remarked by Van Klink et al. (1994d) a clear answer to the question whether longitudinal herd monitoring of privately owned herds is a suitable manner of effect assessment in field trials with a clinical nature such as is reported in this paper, is not easy to give. The results suggest, that comparable differences in productivity can be identified between variables as in the general productivity survey carried out using the same system. It is obvious, that the predictive power of the trials can be improved by alterations in the trial design. These alterations should primarilly aim at increasing the sample size, but under field conditions, as were encountered in the Western Province, the risk is eminent, that practical difficulties become prohibitive in the execution of the trial.

Acknowledgements. The authors wish to thank the Director of the Department of Veterinary and Tsetse Control Services of the Republic of Zambia for his permission to publish this paper. Dr. K.H.J.M. de Baloch is acknowledged for her contributions to the execution of the trial programme.

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14. Klink,E.G.M ,van , J.J.F.M.Corten , K. Frankena, R.C.d e Rooij,D.M . Kalokoni, E.M. Chipos a (1994b). Herdmonitorin g inth etraditiona l cattle keeping industry of Western Province,Zambia , II:Productivity :mortalit y and offtake figures, (submitted).

15. Klink, E.G.M,van , J.J.F.M.Corten , J. Hanks,D.M . Kalokoni and J. Izaks (1994c). Herd monitoring inth e traditional cattle keeping industry ofWester n Province, Zambia, I:Organisationa l design, datamanagement , descriptive aspects,an d the herd structure of trial herds infou r Grazing Management Systems,(submitted) .

16. Klink, E.G.M,van , L.Schoorman , D.M. Kalokoni,E.M . Chipos a and C. Mwango (1994d).Th eus eo f aher d monitoring programefo r the evaluation of the influence of antiparasitic treatments on theproductivit y of traditionally managed cattle inth eWester n Province of Zambia I:intervention s with Triclabendazole and Rafoxanide.(submitted) .

17. Maingi,N. ,an dM.N .Gichig i (1992).Gastrointestina l nematodes incattl eo n four farms inNyandaru a District, Kenya.Bull .Anim .Prod .Afr. ,40 ,9-10 . 18. Majok, A.A., K.H.Zessin ,M.P.O .Bauman n and T.B. Farver (1993). Apparent prevalences of selected parisitic infections of cattle inBah r el Ghazal province, southern Sudan.Prev .Vet .Med . 5,25-33 .

19. Malan, F.S.,R.K . Reinecke and N.A. Roper (1982). Theseasona l incidence of helminth parasites of cattle inth eEaster n Transvaal Lowveld. J. S.Afr .Vet . Ass. 53 (3),179-184 .

20. Michel, J.F. (1972). Economic effects of nematode infections and their control. Proc.VI I Intern.Meetin g onDisease s of Cattle.Wld .Ass .Buiatrics , London, 168-176.

21. Muenstermann, S., and N.R. Tome (1989). Influence of regular tick and helminth control on productivity of small ruminants in the Lolgorien area, Narok District, Kenya.Trop .Anim . Hlth Prod.21 ,247-255 .

22. Nicholson, M.J., andA.R .Sayer s (1987).Relationship s between bodyweight,

163 conditionscor ean dhear t girthchange s inBora ncattle .Trop .Anim .Hlt hProd . 19,115-120 . 23. Pandey,V.S .(1990) .Helmint h infectionso f ruminants inZimbabwe .Proc .6t h Int. Conf.AITVM ,Wageningen ,th eNetherlands ,28t hAug.-1s t Sept.1989 ,p p203-205 . 24. Parent,R. ,e t Th.Alogninouw a (1984).Amélioratio nd e laproductivit éd e l'élevagee nzon etropical .Traitemen t systématiquede svache sgestante sà l'Ivermeetinedan s lesmoi sprécédan t lamis ebas .Rev .Elev .Méd .vét .Pay s trop.,3 7(3) ,359-372 .

25. Parent,R. ,e t F.Sam b (1984).Utilisatio nd e l'ivermectinee nmilie utropical . Étudesu rd e jeunesbovin sa l'embouche.Revu eMéd .Vét . 135,131-134 . 26. Rooij,R.C .de ,an dA.P .Woo d (1990)."Wh oPay sth eBill" :Toward sSustainabl e CattleDevelopmen t inWester nZambia .Proc .6t h Int.Conf .AITVM , Wageningen,th e Netherlands,28t hAug.-1s t Sept.1989 .

27. Troncy,P.M . (1989).Helminth so f livestockan dpoultr y intropica lAfrica . Manual of tropical veterinaryparasitology .C.A.B . International,Wallingford , Oxon,UK .p .138 .

(submitted for publication.)

164 4.3. Reviewingth eresult so fth einterventio ntrials ; reflectionso neconomi cconsequence so ftreatment ,th e statisticaldemand so ftria ldesig nan dfeasibilit yo f treatment.

4.3.1. Introduction.

Theinterventio ntrial sreporte d inth echapter s4. 1an d 4.2 showedonl ya fe wsignifican tdifference sbetwee ntreate d anduntreate danimals .I fpresent ,th emagnitud eo fthes e differenceswa si nmos tcase ssmall .Significan tdifference s werefoun di nth egirt hsize so fth eag egrou pbetwee n1 an d2 yearso fag ei nth eRafoxanid etria lan di nth egirt hsize so f bothth eag egrou po f0 t o1 ,an do f1 t o2 year so fag ei nth e Avermectinetrial .I nal lcase sa large rmea nestimate dgirt h sizefo rtreate danimal swa sfound .A significan tdifferenc e wasals ofoun di nth einterva lbetwee nweanin gan dth enex t delivery inth eRafoxanid etrial .Treate danimal sha da shorte r meanestimate d intervaltha nuntreate danimals .

Inspiteo fth esignifican tdifference sfound ,th e conclusiondraw nfro mth eresult so fth etrial sha dt obe ,tha t onth ebasi so fth emateria lavailabl en ojustificatio ncoul d befoun d forroutin etreatmen to fanimal sagains teithe r intestinalhelminth so rliverflukes .Th ejustificatio no f routinetreatment sca nno tb ebase do neffect salone ,bu t shouldb eevaluate d forthei reconomi cadvantag ea swel l (Michel,1972) . Inthi sevaluatio nno tal lparameter suse di n thetria lhav eth esam eeconomi cimportance .

Inthi schapte rth equestio ni sdiscusse dwhethe ro rno t theparameter so fgreates t importancei nth eevaluatio no fth e economicadvantag eo froutin etreatment si ndifferen thusbandr y systemsi nth eWester nProvinc eca nb eadequatel ymeasure di n thefield .Furthermore ,attentio ni sgive nt oth equestio nwha t alternativesar eavailabl ei fadequat emeasurement sar e difficulto rimpossible .Th eresult sobtaine d forthes e parameterswil lb ediscusse d inrelatio nt oth etria ldesign . Sinceth etria ldesig nma yhav einfluence dthes eresults ,th e influenceo fstatistica lrequirement so nth etria ldesig ni s discussed.Th efact ,tha tth eresult sfoun dfo rthes e parametersdi dno tlea dt oth econclusio ntha troutin e treatmentsar ebeneficial ,wil lb ediscussed .Also ,example s willb eworke dou to fvalue so fth echose nparameter si n relationt oeconomicall yviabl etreatmen tschedules .

165 4.3.2. Parameterso feconomi cImportance .

Liverflukeinfection san dintestina lhelmint hinfection s areregarde da sseriou sthreat st othei ranimal sb yth e livestockowner si nth eWester nProvince .Th eparasite sar e blamed forsuboptima lbod ycondition .Directin gth e interventionevaluatio nprogramm etoward sliverfluk ean d intestinalhelminth swa stherefor econsidere da priorit y (ProjectDocumen to fth eLivestoc kDevelopmen tProjec tWester n Province,1987 ,Chizyuk ae tal. , 1987).Othe r intervention possibilitieseithe rwoul d inevitablyresul ti nlac ko f cooperationfro mth efarmers ,o rwer eextremel ydifficul tt o designunde rth ecircumstance so fth eprojec tarea .

Asstate di nChapte r3 ,farmer sconside rincreas eo fth e herdsiz ea sth emos tdesired ,thoug hindirect ,effec to f treatment.Losses ,particularl ythroug hdeath ,calvin g percentageo rcalvin ginterval ,an dag ea tfirs tcalving ,i n thisorde ro fimportance ,shoul dtherefor eb eregarde da sth e most importantparameter st ob eevaluated .

Deathsan demergenc y slaughters,a son epercentage ,wer e expresseda sth enumbe ro fanimal sdyin go rbein gslaughtere d onth etota lnumbe ro fanimal stha twer epresen ti nth eherd s ina on eyea rperiod .A ssuch ,i ti sa clea ran dsimpl e parameter.Improvement si nthi strai tar eimmediatel yvisibl e forlivestoc kowners .

Usingth ecalvin g intervalseeme deasie rtha nusin gth e calvingpercentag ei nth efiel dtrial sa scarrie dou ti nthi s research.I norde rt ous eth ecalvin gpercentage ,i twoul db e necessaryt ocalculat eth enumbe ro fco wyears ,o rth emea n numbero fcows ,i nth eherds ,o nth ebasi so fth enumbe ro f daysi nth eher da trisk .I nth eproductivit y study (Chapter2 ) andth einterventio ntrials ,th ecompositio no fth eherd s provedt ovar ythroug hth eyear .Man yo fth eanimal stha td o notcalv eo rcalv eonl yonc ema yhav ebee ni nth eherd sfo r shortperiods .Animal sbrough tint oth eher da sa resul to f herdingarrangement so ro nloa nma yofte nonl ysta yi nth eher d fora fe wweek so rmonths .I fth emea nnumbe ro fcow spresent , orco wyears ,i suse d forth ecalculation ,i ti spossibl et o account forchange si nth eher dcomposition .However ,decidin g whichanimal st oinclud ei nth ecalculatio nca nhardl yb edone . Sinceth eag ea tfirs tcalvin gi swidel yvariable ,an d subfertileanimal ssometime ssta yi nth eherd sfo rconsiderabl e periodsbefor ebein gculled ,choosin ganimal solde rtha na certainminimu mag ewoul db earbitrary .Choosin ganimal stha t

166 havecalve da tleas tonc ema yals ob edifficult ,sinc eth e historyo fanimal stha thav ebee ni nth eher dfo rshor tperiod s onlyi softe nunknown .Furthermore ,i ti squestionabl ewhethe r theexpressio n "cowyears "woul db eunderstandabl e forth e livestockowners ,i fuse dfo rextension .

Itwa stherefor edecide dt ous eth ecalvin ginterval , sincethi sparamete rcoul db ederive drathe robjectivel y from recorded calvingdates ,althoug hi tonl yaccount sfo rcow stha t calveda tleas ttwic edurin gth estud yperiod .I twa s considered,tha tth ecalvin ginterva lwa sa neasy ,an d reasonably informativeparamete rt oevaluat einfluence so f environment,management ,climat ean dtreatment .

Asalread yindicated ,i nth epresen tstudies ,th eag ea t firstcalvin gprove dt ob egreatl yvariable .Whil eth emea nag e atfirs tcalvin gwa saroun d3 year san d8 months ,i tvarie d fromaroun d2 year st o6 years .Th eag ea tfirs tcalvin gwa s notsignificantl y affectedb yth efactor si na nanalysi so f variancemode li nwhic hGrazin gManagemen tSystem ,husbandr y systeman dcalvin gseaso nwer einclude da sindependen t variables.Moreover ,cattl eowner sma yals ono tconside ri ta n importantparameter .Servic eo fheifer stake splac elargel y withoutan yattentio no fth eher dmanager .Th ecurren tpractic e is,tha theifer sar egraze dwit hth eres to fth eherd ,an dtha t thebull spresen t inth eher dperfor mthei rdutie swithou tan y supervisiona st oth emomen to rfrequenc yo fservicing .Th eag e atfirs tcalvin ga sa paramete rwil ltherefor eno tb e discussed.Girth ,o rrathe rgrowth ,bear sa relatio nt osexua l maturity (Ogink,1993) ,an dthroug hthi st oag ea tfirs t calving.However ,th eprecis erelatio no fgirt hwit han d influenceo fgirt ho nsexua lmaturit y isno tknow nunde rth e localfiel dcircumstance so fth etrials .Also ,i ti s questionablewhethe ral lheifer sar esired ,an dconseiv ea s soona sthe yhav esexuall ymatured .Therefor eth einfluenc eo f treatmento nth egirt hcanno tb eevaluate d inrelatio nt oag e atfirs tcalving .

Itma yb eargued ,tha ttreatmen teffect sshoul dhav ea certainminimu mmagnitud efo rroutin etreatment st ob e economically justifiable.Th edifferenc ei nth enumbe ro f calvesbor ni ntreate dan duntreate dgroup san dth edifferenc e inmortalit ybetwee ntreate dan duntreate dgroup sshoul db e valued,an dth ecost so ftreatmen tshoul db ecompare dwit hthi s valuei norde rt odecid ewhethe rtreatmen tshoul db eregarde d asfeasibl ean djustifiable .A tthi spoin ti ti sals oimportan t todecid eupo nth eoptima ltreatmen t schedule.I nth etrial s

167 reportedhere ,th etreatmen t scheduleswer erelativel y intensive,sinc eth efirs tobjectiv ewa st oidentif y differencesi nproductivit ybetwee ntreate dan duntreate d animals.I twa soriginall yplanne dt oidentif ydifference s betweentreate dan duntreate danimal si nterm so fproductivity , andi fthe ywer epresent ,evaluat ethe mi neconomica lterms . Next,i twoul dhav ebee nworthwhil et odetermin eth eoptima l treatmentschedul ean dtreatmen tmoment .Sinc eproductivit y differenceswer eno tfoun dt ob esignificant ,thes elas tstep s couldno tb ecarrie dout ..

Inorde rt oillustrat eth eimportanc eo fdifference s betweentreate dan duntreate danimal sfo rth eevaluatio no fth e economicviability ,a nexampl efo ra treatmen tagains t intestinalnematodes ,an dfo ra flukicid etreatmen twil lb e discussed.I nth eassessmen to fth eeconomi cviability ,th e priceo fth edru gan dth eaverag eamoun to fth edru gnecessar y peranima li so fimportance ,a swel la sth etyp eo fanimal sth e treatment isintende d for.Furthermore ,i ti snecessar yt okno w thevalu eo fanimals .

Thecos to fth ecomplet eschem ewit hwhic hth efavourabl e effectma yb eattaine d shouldno texcee dth epotentia lincreas e inth evalu eo fth eher dtha ti sth eresul to ftreatment .Baar s (1987)expresse dth evalu eo fth eincreas ea sth evalu eo f individualadul tanimal sa tsale ,becaus eincreas ei nher dsiz e withon eanima lmean son emor eanima lavailabl efo rsale .Usin g theZambia nnationa lcurrenc ya tth eleve lo f198 7 (1Zambia n Kwacha= approx .0.2 0 US$), fromwhic hyea rth einformatio n originates,th ene tincreas ei nher dvalu euse dwa s68 9K (ZambianKwacha )pe ranimal .Mwafulirw aan dMol l (1991) expressedth evalu eo findividua lanimal si nth eher da sth e valueo fth eaverag eanimals ,o nth ebasi so fth eaverag e liveweighto fanimal si nth eherd .A ta naverag eweigh to f25 9 kilograms,a t1 4K pe rkilogra m liveweighta tth e199 0leve l( 1 ZambianKwach a= approx .0.0 3 US$),th evalu eo fa naverag e animalwoul db e362 6K .Th eadvantageou seffect so ftreatment s canb econsidere da sextr aincome ,abov eth eregula reconomi c resulto f livestockproduction .I twoul dtherefor eprobabl yb e mostappropriat et ous eth esale svalu eo fanimal srathe rtha n thevalu eo fth eaverag eweight .I freductio ni nmortalit yan d increasei nth enumbe ro fcalve sbor na sa resul to ftreatmen t wouldamoun tt o1 percent ,th ecos to fth etreatmen tschedul e shouldno texcee dthi sfigur epe r10 0animal spe ryear .Fo r farmerst oaccep troutin etreatment sa sadvantageous ,th ecost s shouldprobabl yb ewel lbelo wthi sfigure .

168 Inth eexamples ,price so fdrug san do fanimal swil lb e useda sprovide db yth eprojec tconsultan to fth eLivestoc k DevelopmentProjec t (DeRooij ,persona lcommunication )a tth e 1994level .I nth edru gretai lschem etha ti sru nb yth e project,Flukazol eha sreplace dRafoxanide ,an dAlbendazol eha s replacedThiabendazole .Sinc eth eprice sfo rthes edrug sar e reasonablycomparabl ewit hthos eo fth edrug stha twer euse d forth einterventio ntrials ,th e199 4price so fth ene wdrug s mentionedwil lb euse d inth ecomparison .

4.3.2.1. Assessingth eeconomi cviabilit yo ftreatment s againstgastro-intestina lparasites .

Inth einterventio ntrials ,th etreatment sagains tgastro intestinalparasite swer eonl ygive nt oyoun ggrowin ganimal s untillth eag eo ftw oyears .Adul tanimal swil lhav eacquire da certainleve lo fprémunit yagains t intestinalhelminths .Th e damagedon eb ythes eparasite swil ltherefor eb elimited . Routinetreatmen t shouldsuppor tth egrowin ganimal san d protectthe magains tmassive ,an ddevastatin g infections,whil e notpreventin greinfectio nentirely .I nth einterventio ntrial s itwa sfound ,tha tals oi nth etreate dgrou peg gsheddin g occurred.I ncalculatin gth eeffect-cos tbalance ,th esam e principle,treatmen to fyoun ganimal sonly ,i sused .

Onth ebasi so fth eaverag eweigh to fth eanimal sbelo w theag eo ftw oyears ,o fth edivisio no fth eanimal so nth e rangeo fth eweight ,an do fth edos erat eo fAlbendazol e( 1 bolusfo reac h6 0kilogramme so fbod yweight) ,th eapproximat e numbero fbol ica nb ecalculated .A napproximatio no fth e weightca nb emad eusin gth eformul afo rth ecalculatio no f weightsfro mth egirt hmeasurements ,derive db yCorte n (1988), usingaroun d45 0record so fweight san dgirth so fBarots e cattle.Th eapproximation so fth eweight sca nb emad eusin gth e averagegirt hmeasurement sfoun di nth eproductivit ystudy , reportedo ni nChapte r2 .Approximatel y 210bol iwil lhav et o beuse dt otrea t10 0animals .A ta pric eo f11 0Zambia nKwach a perbolus ,th ecos to fon etreatmen t fora grou po f10 0animal s belowth eag eo ftw oyear sca nb eestimate da t23.10 0Kwacha .

Thesale spric eo fanimal si s22 0Zambia nKwach ape r kilogramme liveweight .A ta nestimate daverag ebod yweigh ta t saleo f35 6kilogramme s (Baars,1987) ,on eanima lwoul d generate78.32 0Kwacha .Thi sshows ,that ,i froutin etreatmen t wouldreduc emortalit yb yon epercent ,thi seffec tshoul db e attainedb ya schedul econsistin go fmaximall y3 treatment s annually.

169 Asi sdiscusse d inChapte r3.1. ,th eris ko finfection s withintestina lhelminth sincrease sdurin gth ecours eo fth e wetseason .A treatmen tschedul eshoul db econcentrate d inthi s period.I tcoul db econsidere dt ogiv ethre etreatment sa t6 weekinterval si nth elas tthre emonth so fth ewe tseason ,whe n thecontaminatio no fth epastur ei sa tits 'peak .I ntha tcase , onetreatmen twoul db egive nearl yJanuary ,on ehal fFebruar y andon ea tth een do fMarch ,jus tbefor eth eonse to fth edr y season.Obviously ,variation so nthi sschedul ear eimaginable . Thefirs ttreatmen tcoul d forexampl eb egive nearlier ,i nth e courseo fNovembe ro rDecember .I fa schedul eo fthi skin di s used,th eanimals ,whil egrazin go ncontaminate dpastures ,ar e exposedt omoderat einfectio nlevels .I nthi sway ,the yd ohav e achanc eo fdevelopin gpremunit yagains tintestina lhelminths . Ploeger (1989)demonstrated ,i ncommercia ldair ycattl ei nTh e Netherlands,tha tth eexten tt owhic hyoun ganimal sar eexpose d to (moderate)helmint hinfection sinfluence sthei rcapabilit y ofcopin gwit hthes einfection si nlate rlife .

4.3.2.2. Assessingth eeconomi cviabilit yo fflukicid e treatments.

Theflukicid etrial swer egive nt oal lyoungstoc kbelo w theag eo ftw oyears ,an dt oal lcow sove rth eag eo ftw o years.Oxe nan dbull sove rtha tag ewer eno ttreated ,sinc ei n thisgroup ,apar tfro mmortality ,n oparameter srelate dt o increasingth esiz eo fth eher dwer et ob emeasured .I ti s likely,tha t inpractic eth esam elin eo fthough twoul db e followed,althoug hfarmer sma yconside rtreatmen to foxe nt o increasethei rwor koutput .Thi swould ,however ,onl yb e viable,i fth eoxe nwer euse dt oth emaximu mo fthei rability . Therei sn oevidenc etha tthi si sth ecase .I nth eevaluatio n oftreatmen ttherefore ,a schedul ewil lb econsidere d inwhic h thesam eanima lcategorie sar einclude dtha twer einvolve di n theinterventio ntrial .

Thedos erat eo fFlukazol ei shal fa bolu spe r7 5kg .o f bodyweight .O nth ebasi so fthis ,an do nth ebasi so fth e weightrang ei nth egrou pt ob etreated ,th eapproximat enumbe r ofbol ineede d foron etreatmen to f10 0animal swoul db earoun d 156boli .A ta pric eo f12 0Zambia nKwach ape rbolus ,th ecos t ofon etreatmen t fora grou po f10 0animal sca nb eestimate da t 18.720Kwacha .

Ifonl ymortalit y istake nint oaccount ,an di twoul db e reducedb yon epercen tthroug hroutin etreatments ,th eschedul e thatproduce sthi seffec tshoul dconsis to fno tmor etha n4

170 treatmentsannually .Th ecalvin ginterva lma yhoweve rals ob e influencedb ytreatment .

Inth einterventio ntrials ,difference si nth ecalvin g intervalswer efoun d infavou ro ftreatments ,althoug hthe y wereno tsignificant .A nimpressio no fth enumbe ro fextr a calvesbein gbor ni nth eherd sa sa resul to ftreatmen tca nb e derivedthroug hcalculate dcalvin gpercentage s fromth ecalvin g intervalsmeasured .A calculate dcalvin gpercentag eca nb e derivedb ydevidin g36 5b yth ecalvin g intervalan dmultiplyin g theresul twit h100 .Th edifference si ncalculate dcalvin g percentagesbetwee ntreate dan duntreate dcow srang efro m1 % (inth eRafoxanid etrial )t o7 % (inth ecombine d Rafoxanide/Thiabendazole).Th eextr arevenu eresultin gfro m thiscoul db ebetwee n39.16 0an d227.12 8Kwacha .

Therevenu eearne dthroug hth etreatmen t is,i nth e examplesmentioned ,bi genoug ht ofinanc eth edrug sfo ra treatmentschedul ecomparabl et otha tuse di nth einterventio n trials,i.e .a schedul ei nwhic hfou rtreatment spe ryea rar e given.Suc ha schedul ei si nlin ewit hth eschedule ,propose d byArmou r (1981)an devaluate db yOwe n (1984).Treatmen tshoul d probablya tleas tb ecarrie dou ta tthre emonthl yinterval s aroundth eperiod stha tth eanimal sar eexpose dmos tseverely , i.e.whe nthe ygraz eth efloodplains .

4.3.3. Statisticalaspect so fth einterventio ntrials .

Aswa sstate di nth eintroduction ,th etria ldesig nma y haveplaye d arol ei nth eresult sobtained .Therefore , attention isgive nt ostatistica laspect so fth einterventio n trialstha twer ecarrie dout .Statistica laspect st ob e discussed areth esampl esiz ean dth echoic eo fth etria l herds.

Thesampl esiz ei sa critica lfacto ri nth edesig no f trials.Marti ne tal . (1987,p .45 )sho wformula efo rth e determinationo fsampl esiz ebot hfo rparameter swit habsolut e values,wher eth eresul ti sexpresse da sa proportion ,an dfo r parameterswit hcontinuou svalues ,wher eth eresul ti s expressed asa mean .Thes eformula ewer eals opresente db yPut t etal . (1988)an dFleis s (1986)respectively .

Allrecord swer etake no nth ebasi so finformatio no n individualanimals .Th eanalysi suni twa sals oth eindividua l animal.Th eherd ,therefore ,ha dt ob einclude d inth emodel s used forth eevaluatio no fth eOdd sRati ofo rdeat han d

171 slaughter,a swel la sfo rth eevaluatio no fcalvin ginterva l andth elactatio nintervals ,an dth egirth ,i norde rt oaccoun t forit sinfluence .

4.3.3.1. Samplesize sfo rth eevaluatio no fmortality .

Theoveral lpercentag eo fanimal sdyin go rbein g slaughtered foundi nth eproductivit y studywa s9. 1 %.A valu e inthi srang eca nb echose na sth eexpecte dvalu efo rth egrou p ofuntreate d animals,fo rexampl e1 0% ,an d6 % a sth evalu e forth etreate dgroup .A ta confidenc eleve lo f .90,an da powero f .80,th eapproximatio no fth esampl esiz efollowin g fromth eformul a (Martine tal. ,1987 ,Put te tal. ,1988 )woul d be56 5subject sfo rtreatmen tan dcontro lgroup seach .A t higherconfidenc eo rpowe rlevel sth enumbe ro fsubject swoul d haveha dt ob econsiderabl ylarger .

Ifth eresult so fth elogisti cregressio ni nal l interventiontrial sar eobserved ,a favourabl eeffect ,i.e .a decreasei nth eOdd sRati ofo rdeat han dslaughte ra sa resul t oftreatmen twa sfoun dfo rth eThiabendazol etreatmen t( a mortalityo f20. 7% i nth econtrol ,an do f10. 5% i nth e treated group).T oobtai nthes eresult ssignifican ta ta .9 0 confidenceleve lan da powe ro f .80,th esampl esize sa sa resulto fth eformul ashoul dhav ebee n156 .Th eThiabendazol e treatmentwa si nfac tsignifican ta tth e .90level ,bu tth e percentageanimal stha tdie do rwer eslaughtered ,als oi nth e controlgroup ,wa smuc hhighe rtha ni nth eothe rtrial s (Chapter 4.2).Som eattentio ni sgive nt othi si nth e discussiono fChapte r4.2 .

Forth elogisti cregressio nmodel s (Hosmeran dLemeshow , 1989)use d forth eanalysi so fth eOdd sRati ofo rdeat han d emergency slaughter,th enumbe ro fanimal si nth esampl ewa s belowth ecalculate drequirement ,eve ni fconsidering ,a s statedb yPut te tal . (1988),tha t "giventh edegre eo f arbitrarinesswhic hwil lusuall yb einvolve d inassumin gvalue s forth etru eproportions ,i ti st ob eexpecte dtha tth e indicated samplesiz ewil lneve rb ebette rtha na roug h approximation".

Althoughth enumbe ro fdeaths ,togethe rwit hth eemergenc y slaughter figure,shoul db eregarde da sth emos timportan t parameter,i twa slogisticall y impossiblet oengag eenoug h herdsi nth etrial st omee tth etheoretica lrequiremen to fa t least56 5animal spe rgroup .Th eleve lo fsupervisio nha dt ob e high,sinc eth eAfrica nlivestoc kowner srarel yar euse dt o

172 recordkeeping .Also ,th efiel dstaf finvolve dneede dintensiv e supervision inth ecorrectnes so fthei rrecor dkeepin gan dth e correctdeterminatio no fdos erate san dapplicatio no f treatments.Anothe r importantelemen ti sho wt omotivat eenoug h farmerst oparticipat ei nth etrial sfo ra considerabl elengt h oftime .Thi si sa nelemen twhic hals oplay sa par ti nth e choiceo fth etria lherds ,whic hwil lb ediscusse d later.Th e investmento ftim ean dpersonne lcoul dno tb eincrease d inth e research,eve nconsiderin gtha tdemand so freachabilit y determinedpartl yth echoic eo ftria lherd sinvolved .

Notwithstandingth efact ,tha ta nadequat esampl esiz e greatlyenhance sth epredictin gpowe ro fan ytrial ,practica l limitationsan dimplication s (Baarsan dEgger ,1993 )a swel la s costconsideration s (Martine tal. ,1987 )ma yb eo finfluenc e onth epossibilitie si nan ygive nsituation .Circumstance sma y arisei nwhic hpreferenc eha st ob egive nt oles spowerful l results (Meinertan dTonascia ,1986) .

4.3.3.2. Samplesize sfo rth eevaluatio no fth ecalvin g interval.

Inth eproductivit y study,th emea ncalvin g intervalwa s around 580days .Th evalue sfoun di nthi sstud ywer euse dfo r determinationo fth eapproximat esampl esizes .I norde rt ofin d significantdifference sbetwee nth ecalvin g intervalslarge r than60 0day s (slightlyhighe rtha nth eoveral laverage )fo r untreated and53 0day s (animprovemen to froughl y2 0day si f comparedwit hth eshortes tcalvin g intervalsi nth e productivity study)fo rtreate danimals ,wit ha standar derro r ofaroun d 50days ,th enumbe ro fsubject si nth esampl eshoul d be8 fo rbot htreatmen tan dcontro lgroup ,a ta confidenc e levelo f .90an da powe ro f .80 (Fleiss,1986 ,Marti ne tal. , 1987).Marti ne tal .(1987 )recommended ,tha t ifth esampl e sizewoul d fallbelo w10 ,th enumbe rshoul db edoubled .I nthi s casea sampl esiz eo f1 6subject swoul dhav et ob echosen .

Theresult so fth einterventio ntrial sshow ,tha ti nal l interventions inwhic hth ecalvin ginterva lwa sevaluated ,i.e . allliverfluk etreatments ,th etreate dcow sha da shorte r calving interval,bu ti nal lcase sth edifference swer eno t significant.I fth eformul ai sapplied ,i nth eTriclabendazol e interventionth esam eresult swoul dhav ebee nexpecte dt ob e significantwit ha sampl esiz eo f1 2pe rtreatmen tan dcontro l groupeach .I nth eRafoxanid einterventio nth esampl esiz eha d tob e110 ,an di nth ecombine dRafoxanid ean dThiabendazol e treatmenta calculate d approximatesampl esiz eo f7 (i.e.a

173 samplesiz eo f14 )ha dt ob esufficient .

Thenumbe ro frecords ,a scalculate d fromth eresult so f theproductivit y study,wer ewel labov eth erequire dnumber . Forth eevaluatio no fth ecalvin ginterva li nth einterventio n trials,th esampl esize swer etherefor eexpecte dt ob e sufficiently large.I fmultivariat eanalysi so fvarianc ei s performed,eac ho fth evalue so feac hindependen tvariabl eo r ofeac hcombinatio n (interaction)o findependen tvariables , i.e.eac hcel lo fth emodel ,shoul dcontai na tleas ta certai n minimumnumbe ro frecord so robservations .Ofte n5 observation s percel lar econsidere dt ob eth eminimu m (Greenland, 1985). Thisaffect sth eadequac yo fth etheoreticall y calculated samplesize .Th emor eindependen tvariables ,an dinteraction s of independentvariables ,ar eincorporate d inth emodel ,th e moresubject sshoul db einvolve d inth etrial .Th emodel suse d inth einterventio ntrial sme tth erequiremen to fhavin ga t least5 subject spe rcell .

Apartfro mth ereason salread ymentione d forth edecisio n tous eth ecalvin g intervalrathe rtha nth ecalvin gpercentage , samplesiz econsideration sar eals oo fimportance .I norde rt o finddifference si nth erang eo f1 t o7 % ,significan ta ta confidenceleve lo f .90wit ha powe ro f .80,i fth eproportion s arei nth erang eo f5 0t o6 0% ,th esampl esize swoul dhav et o befro m60 3fo rth ebigges tdifferenc et oove r3000 0fo rth e smallest.A swa sth ecas ewit hth emortality ,i ti simpossibl e tomee tthes erequirement sunde rth efiel dcondition s encountered inthes etrials .

4.3.3.3. Thechoic eo ftes therd san danimals .

Theherd sinvolve d inth etria lwer eno tchose na trandom . Thecondition sunde rwhic hcattl ei skep ti nth eprovinc emad e itdifficul tt ochoos etria lherd srandomly .Firstly ,th e farmerha dt ob ewillin gt ocooperate .The yha dt oregiste r eventsi nth eherd si nbetwee nvisit sb yth eveterinar y assistants.Secondly ,th einfrastructur e inth eprovinc e demandedtha therd sha dt ob echose ntha twer eeas yt oreac ho n aregula rbasis .

Froma statistica lpoin to fview ,rando mselectio no f herdsan drandoml yassignin ganimal so rherd st oeithe r treatmento rcontro lgroup si spreferrabl e (Martine tal. , 1987).Th elogisti ccircumstance s inth estud yma ytherefor e undoubtedly haveplaye da par t inth efac ttha tn osignifican t resultscoul db eobtained .Th edirectio nan dmagnitud eo fsom e

174 ofth eindependen tvariables ,a sfoun di nbot hth eproductivit y study,i nwhic h5 2herd swer einvolved ,an dth einterventio n trials,i nwhic h3 t o6 herd swer einvolved ,wer ever ysimilar . Theherd si nth einterventio ntrial swer echose nfro mthos e involvedpreviousl y inth eproductivit y study.Thi ssuggest s thatth esampl eo fherd sinvolve d inth einterventio ntrial s didno tsubstantiall ydiffe rfro mth ecomplet egrou po f5 2 herds.However ,als oth esampl eo f5 2herd scoul dno tb e randomlychose nfo rreason salread ymentioned .

Inth etrial sth eanimal swer eassigne dt oeithe r treatmento rcontro lgroup ,matche d forag ean dsex .Th e helminthexposur eleve lo fth eanimal swa sno tuse di nmatchin g them.Thi swoul dpos econsiderabl epractica ldifficulties . Faecalsampl eresults ,fo rexample ,canno tb euse dfo rthi s purpose,sinc ethe yd ono treliabl yrepresen tth einfectio n level.Serologica lmethod sd ono tgiv einformatio no nth e statuso fth einfectio no fth emomen teither .Also ,th e infectionleve lma yvar ygreatl ythroug htime .Animal stha t havea comparabl ehelmint hexposur eleve la ta certai nmoment , dono tnecessaril ycontinu et ohav eth esam estatus .I twa s thereforeassumed ,tha texposur et oinfectio nwa sfairl yequa l foral lanimals .

4.3.4. Viabilityo froutin etreatments .

Ifonl yth ecos to fth edru go npurchas e forth elivestoc k owneri stake nint oaccount ,eve nsmal limprovement so fsom e productivityparameter swoul dsee mt omak eroutin etreatmen t justifiable.A tpresent ,n ofee sfo rservice srendere dar e chargedb yth eDepartmen to fVeterinar y andTsets eContro l Services.Sinc eintroductio no ffee sfo rservice si sbein g planned,th ecost so fapplication ,i.e .o flabou ran do fth e assistanceo fth eveterinaria no rth eveterinar yassistant ,ma y indu ecours einfluenc eth eoutcom eo fth eexample snegatively . Themeasur eo fthi sinfluenc edepend so nth eproportio no fth e totalapplicatio ncost stha twil lb econstitute db yth edru g costs.

Hardlyan ysignifican tdifference swer efoun dfo r treatment,whil efactor srelate dt omanagemen tan denvironmen t did showsignifican tdifferences ,bot hi nth eproductivit y study (chapters2. 2 and2.3 )an di nth einterventio nstud y (chapters4. 1an d 4.2).Th eimportanc eo fenvironmenta l factors,specificall y illustratedb yth edifference si n productivitybetwee nGrazin gManagemen tSystems ,betwee n periodsan dbetwee nherds ,suggests ,tha tmuc hmor ema ystil l

175 begaine dthroug himprovement si nanima lhusbandr ypractices , managementan doptima lus eo fgrazin gresources .

AsMiche l (1972)ha sstate dstrongly ,i ti sno tjustifie d toinves ti ndrug st oattai na certai nse to fgoals ,i fther e areother ,cheape rway so fattainin gth esam egoals .On eo fhi s examplesdeal twit hsteers ,bein gtreate dagains tintestina l wormsshortl ybefor ebein gstable d forth ewinter ,whil ethe y wereno texpecte dt oreac hthei rslaughte rweigh tbefor eth e endo fth establin gseason .Th eanimal sar eexpecte dt o overcometh einfectio nlargel ydurin gth establin gseaso ni f theyar eno ttreated .Th ecos to fth eextr afeed ,necessar yt o allowth eanimal st omak eu pfo rth eretardatio ni ngrowt ha sa resulto fintestina lhelmint hinfection si sfa rles stha nth e costo fde-worming .

Followingthi slin eo fthough t (Michel,1972) ,an dtakin g intoconsideratio ntha tanimal si nth eWester nProvinc ear eno t raised fora ready-to-sal eweight ,an dtha ttreatmen tdi dno t significantlyimprov eproductivity ,i ti sno tjustifie dt o recommendroutin etreatments .Moreover ,nutritiona l factors (Troncy,1989 ,Oakle ye tal. , 1979),o nwhic hmanagemen tan d environmentexer ta critica l influence,mas kth eeffec to f infectionand ,therefore ,o ftreatment .

4.3.5. Discussionan dconclusions .

Theloca llogisti ccircumstance sunde rwhic hth e interventiontrial swer ecarrie dout ,hav eexerte da ninfluenc e onth eresult so fth etrials .Th efact ,tha therd st ob e involved inth eher dmonitorin gprogramm ecoul dno tb echose n atrandom ,i son eo fthes ecircumstantia l factors.Mor e important,th esampl esize sdi dno tallo wfir mconclusion s regardingth eOdd sRatio sfo rdeat han demergenc yslaughters . Theresult so fth eevaluatio no fth eOdd sRatio swer etherefor e inthi srespec tprimaril yregarde da sindicativ ean d descriptive.Somewha tunfortunat ea si tma ybe ,carryin gou ta studyo fthi skin di nth eframewor ko fa livestoc kdevelopmen t projectmeans ,tha tther ear elimitation st oth eexten to fan d theavailabl eresource sfo rresearch .

Itwa sdecide dt otr yan destablis ha smuc ho fth egoal s aspossibl ewithi nth eprospecte dprojec tperio d (Project Documento fth eLivestoc kDevelopmen tProjec tWester nProvince , 1987, Chizyukae tal. , 1987).Therefore ,bot htreatment s againstintestina lhelminth san dagains tliverflukes ,a swel l asa grou pi nwhic hbot htreatment swer egiven ,wer einclude d

176 inth eresearch .Becaus eo fth efact ,tha tlogisti c difficultiesassociate dwit hphysica lmonitorin go fsufficien t animals,t omee tth erequiremen to fth eoutcome smeasure da sa proportion,woul dprov eprohibitiv efo rth eexecutio no fth e research,i twa sdecide dt ocarr you tth etrial sa sdescribed .

Theconsideration ,tha tfiel dlogisti cdifficultie s determinedth epossibilitie so fth etria ldesign ,als o underliesevaluatio no fsom eway so fovercomin gth eproble mo f insufficient samplesize .Increasin gsampl esiz ecoul db e attained forexampl eb ycarryin gou tfewe rdifferen ttrials , buteve nthen ,wit hth enumbe ro fanimal savailabl efo rth e exercise,th erequiremen twoul dno tb emet .Meta-analysis ,i n whichtreatment sar epoole dan danalyse d forthei reffec t againstth epoole dcontrols ,coul db eanothe rpossibilit y (Willeberg,1993) .Eve ni fthi smetho dwoul db eused ,th e samplesize sma yb eto osmall .

Anotherpossibilit y ist ous ea sequentia lsampl esiz e design (Meinertan dTonascia ,1986 ,p .72) ,i nwhic hth etria l iscontinue dove ra prolonge dperio do ftime .Th esampl esiz e involved inth etria la tan ygive ntim eca nb esmalle ri nthi s typeo fdesign .Trial scarrie dou tusin gthi sdesig nar e continueduntil lth edifferenc ebetwee ntreate dan duntreate d groupsexceed sa predefine dboundar yvalue .Th eduratio ni s determinedb yth erunnin gdevelopmen to fth eresults . Logistically itma ysee measie rt ocarr you ttrial sfo ra longerperio d ina relativel ysmal lnumbe ro fherds .However , therei srarel ytim eenoug hi nlivestoc kdevelopmen tproject s tocarr you ttrial sfo ra relativel y longperio do ftim e (Chizyukae tal. , 1987).Furthermore ,motivatio no fpersonne l andher downer sinvolve dma y inth elon gru nbecom e increasingly difficult.On eelemen ti nthi srespec tma yb eth e fact,tha ta spli ther dtria li sused .I fimprovement sbecom e detectablei nth etreate dhal fo fth eherd ,i ti sver ywel l possibletha tth eowne ro fth eherd swil li nth elon gter m insisto ntreatmen to fth eentir eherd .I ti stherefor ehighl y unlikely,tha t itwoul db epossibl et oestablis ha sample , largeenoug ht omee tth eminimu mrequirement sa sdiscussed ,o r maintaina researc h situationi nth efiel d longenough ,eve ni f theresource sfro mth eprojec twer eno ta slimiting .

Forth ecalvin ginterval ,th enumbe ro frecord savailabl e seemedt ob esufficientl y large,i nvie wo fbot hth eminima l samplesiz ean dth eminima lnumbe ro frecord spe rcel l (Greenland, 1985).Th esituatio ni nwhic htrial sar ecarrie d outma yals ob econnecte dwit hth esampl esiz ean dth emode l

177 thati schose nfo rth eevaluatio no fparameters .Fo rwel l controlledon-statio ntrials ,o rtrial si nwhic hal lsubject s aremaintaine dtogether ,th esampl esiz ema ypossibl yb e smallertha ni nth ecas eo ffiel dtrials .Becaus eth e circumstancesar emor eeasil ycontrôlable ,simple rstatistica l modelsca nb euse dfo rthes etrials .Th efollowin gtw oexample s ofrelativel y smallsampl esize sma yb ementioned .Chic ke tal . (1980)use d6 group so f8 Herefor d steerst oidentif y significanteffect so ngrowt ho fthre elevel so ffluk e infectionsan dtw ostockin grate si na non-statio ntria li n Australia.Especiall y inth efirs t1 2week so fth etrial , effectso fbot hwer esignificant .I na tria lcarrie dou ta tth e Facultyo fVeterinar yMedicin ei nKhartoum ,Sudan ,i norde rt o assessth eeffec to ftreatmen twit hAvermectin eo ngrowth , Abdalla (1989)coul dno tprov esignifican tadvantage so f treatment.Th etria lconsiste do f2 0sheep ,divide d ina treatmentan da contro lgroup ,an d2 0cattle ,als odivide d ina treatmentan dcontro lgroup .Th efac ttha tn osignifican t differenceswer efound ,wa sattribute dt obot hsampl esiz ean d theshor tduratio no fth etrial .A muc hlarge rsampl esize , thoughth etria lwa scarrie dou ti na singl eherd ,wa suse db y Parentan dSam b (1984).Th esignifican tpositiv eeffec to f Avermectineo ngrowth ,i fcompare dwit htreatmen twit h tetramisole,wa sdetecte d ina tria li nwhic h10 0ou to f60 0 newlybough tcalve swer erandoml yselected .O fthi sgrou po f calves,5 0wer etreate dwit hAvermectin ean d5 0wit h Tetramisole.Th eanimals ,N'dama-Zeb ucrosses ,wer emaintaine d forfattenin gi nth eCa pVer tregio no fSenegal .

Forfiel dtrials ,analysi smodel sar ei ngenera llikel yt o bemor ecomplex ,and ,a salread ymentioned ,a minima lnumbe ro f observationso rrecord spe rcel lwil lb erequired . Nevertheless,i nth etria lreporte db yParen tan dAlogninouw a (1984), inwhic hth einfluenc eo ncal fweigh tan dmortalit yo f Avermectinetreatmen to fdam si nth elas tmonth so fpregnancy , atota lo f4 5treate danimal san d3 5contro lanimal swer e involved.Th eanimal swer eprivatel yowne dDjakor é (Gobra-zebu andN'dam acrosses )i nvariou svillage si nth eRethb aregio no f Senegal.A considerabl esignifican tdifferenc ei ngrowt hwa s found.Also ,th eAvermectin egrou pshowe dn ocal fmortalit y whileth emortalit y inth econtro lgrou prange daroun d 10% .

Theuni to fanalysi swa sth eindividua lanimal .Thi swa s possible,becaus ea split-her ddesig nwa suse di nwhic hbot h treated anduntreate danimal sgraze d inth esam eherd .I norde r toaccomodat efo rth efac ttha tsevera lherd swer eused ,th e herdha dt ob einclude d inth emodels .Usin gth eher da suni t

178 ofanalysis ,fo rexampl eb yassignin gcomplet eherd st oeithe r thetreatmen to rth econtro lgroups ,woul dhav emad ei t necessaryt oinvolv elarge rnumber so fherd stha nwer euse di n thetrials .I twoul dhav ecause dconsiderabl ylarge r difficulties inmatchin gan di nth epractica lexecutio no fth e trials.A swa salread ystate di nchapte r3 ,i twa sassumed , thatth einfluenc eo fth etreatmen tgrou po nth eexposur eo f thecontro lgrou pwa slimited ,becaus eo fth efac ttha t pasturesar ecommunal yused ,an dtha treservoir so finfectio n ingam eanimal sexisted .Usin gindividua lanimal sa sunit so f analysis,an dtreatmen tan dcontro lgroup swithi neac hherd , wastherefor ejustified .

Besidesth equestion ,whethe ro rno tth eresult so fth e trialshav ebee ninfluence db yth ecircumstance sunde rwhic h thetrial swer ecarrie dout ,ther ei sevidenc etha tintestina l nematodesar eno tmos timportan t factorsi naffectin g productivity.Th eresult so fth efaeca lsampl eexaminations ,a s wella sth eunpublishe ddat ao fBonger s (1987),show ,tha tth e extensityo fth einfection swit hintestina lnematodes ,i.e .th e proportiono fth eherd sinfected ,i sgenerall ymoderate . Althoughth eEP Gno tnecessaril yreflect sth estatu so fth e infection (Parentan dSamb ,1984) ,th efac ttha tal lEPG' swer e consistently lowwoul dsuggest ,tha tth elevel so finfectio ni n thehost swa sals ono tmor etha nmoderate .

Liverflukesar ewidel ypresen t (Jorgensenan dKamukwai , 1977).Apar t fromth eincidenta lan dindividua lcase so facut e fasciolosis,howeve r (personalobservation) ,th eanimal sar e ablet omanag ethi sinfectio nquit ewel l (Kendallan dParfitt , 1975).A sfactor sinfluencin gproductivity ,liverfluk e infectionssee mt ohav elittl epractica limportance .

Aswa salread ystated ,i ti sunlikel ytha ttreatmen tplay s a significantpar t inreducin gpastur econtamination ,bot hfo r liverflukesan dfo rintestina lhelminths .Influencin gth e exposureo fth eanimal si stherefor eals ono ta nargumen tfo r treatment.

Thenon-significant ,bu tindicativ efavourable ,result s obtained inth etrial sfo rth emos timportan tparameters , shouldno trais eeve nth eslightes tsuggestio ntha ttreatmen t wouldhav ea beneficia leffec to nproductivity .Cattl eowner s mayadministe rth edrug sinjudiciously ,o rma yno tb eabl et o followroutin eschedules .Whil eprobabl ybein gconvince do f undertakingth erigh taction ,the yma yinves tlarg esum so f moneywithou tgainin gan yreturns .

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13. Martin, S.W., A.H.Mee kan dP .Willeber g (1987).Veterinar y Epidemiology. Principles andmethods . Iowa StateUniversit y Press,Ames , Iowa, USA. 14. Meinert, C.L.,an dS .Tonasci a (1986). Clinical trials.Design , conduct,an d analysis.Oxfor d University press.Ne wYork , Oxford. 15. Michel, J.F. (1972).Economi c effectso fnematod e infectionsan dthei r control. Proc.VI IIntern .Meetin go nDisease so fCattle .Wld .Ass .Buiatrics , London, 168-176.

16. Mwafulirwa,C ,an dH.A.J . Moll (1991). Economicso fth ecattl ean dcro psub - sectorso fWester n Province.Analytica l summary. Department ofVeterinar yan d

180 Tsetse Control Services, Livestock Development Project, Socio-economic Analysis Team, Western Province, Zambia. 17. Oakley, G.A., B.Owe n and N.H.H.Knap p (1979). Production effects of subclinical liver fluke infection ingrowin g dairy heifers.Vet.Rec . 104,503-507 . 18. Ogink, N.U.M. (1993). Genetic size and growth ingoats .Ph.D .Thesis , Agricultural University Wageningen, The Netherlands. 19. Owen, I.L. (1984). Production effects of the liver fluke Fasciola hepatica on weaner cattle inPapu a New Guinea. Trop.Anim . Hlth Prod. 16,158-160 . 20. Parent, R., et Th.Alogninouw a (1984).Amélioratio n de laproductivit é de l'élevage en zone tropical.Traitemen t systématique des vaches gestantes à l'Ivermectinedan s lesmoi sprécédan t lamis ebas .Rev .Elev .Méd .vét . Pays trop.,3 7 (3),359-372 . 21. Parent, R., et F.Sam b (1984).Utilisatio n de l'ivermectinee nmilie u tropical étude sur de jeunes bovins a l'embouche. Revue Méd. Vét. 135,131-134 . 22. Ploeger, H.U. (1989). Effect of nematode infections on productivity of young and adult cattle on commercial dairy farms.Ph.D .thesis ,Uageninge n Agricultural University, The Netherlands. 23. Provincial Veterinary Officer (1987). Livestock Development Project Western Province.Projec t Document.Departmen t of Veterinary and Tsetse Control Services, Western Province, Mongu, Zambia. 24. Putt, S.N.H., A.P.M. Shaw,A.J .Woods , L. Tyler and A.D.James (1988). Veterinary epidemiology and economics inAfrica .A manua l for use inth edesig n and appraisal of livestock health policy. ILCA Manual No.3 . International Livestock Centre forAfrica , AddisAbaba , Ethiopia. 25. Troncy, P.M. (1989). Helminths of livestock and poultry in tropical Africa. Foreword. In:Shah-Fisher , M. and R. Say (Transi.).Manua l of tropical veterinary parasitology (Engl.Ed.) .C.A.B . International, UK.

26. Willeberg, P. (1993). Bovine somatotropin and clinical mastitis: epidemiological assessment of the welfare risk.Livestoc k Prod. Science, 36,55-66 .

181 CHAPTER5

Generaldiscussion .

183 5.1. Theai mo fth ethesis .

Thegenera lai mo fth ethesis ,assessin gth eus eo f longitudinalher dmonitorin g ina traditiona lcattl ekeepin g system forth edescriptio nan didentificatio no finfluence so n productivity,shoul db eevaluate d inconnectio nwit hth e relevanceo fth eresult sfo rlivestoc kdevelopmen t inth e WesternProvince .Th eresult sshoul dtherefor eb eviewe di n relationt oth eobjective stha twer eformulate dfo rth e programme.Thes ewer eidentificatio no fconstraint san d specificveterinar yneeds ,resultin g inth eformulatio no f appropriateextensio nmessages ,an dstudyin gth estructur eo f theprovincia lcattl epopulation .

Factorsinfluencin gproductivit yma yb emany ,an dvariabl e ofnature .Describin gan didentifyin gthe mshoul dg otogether , ifpossible ,wit hsuggestion sfo radjustment so rimprovement s aimeda timprovin gproductivity .Thes efactor sma yals o exerciseinfluence so neac hother .Factor so fsocio-economic , aswel la so fenvironmenta lnatur ema yinfluenc eth e possibilitiest oadjus ttechnica laspect san dmanagemen t inth e WesternProvinc eherds .

Inthi schapter ,th einfluence so fmanagement ,environmen t ando fsocio-economi c factorso nproductivity ,a sderive dfro m thestudie scarrie dou tfo rthi sthesis ,with ,wher e appropriate,thei rinterrelationships ,ar ediscussed .Th eaim s ofthi schapte rar et oexamin eth epossibilitie so f productivity improvement (5.2.,5.3. ,5.4.) ,withi nth elimit s determinedb yth einterrelate d influenceso nproductivit yan d bysocio-economi cpattern s (5.5.),an dt oelaborat eo n approachesfo rproductivit y improvementan do nextensio nan d furtherresearch .

5.2. Herdmanagemen t inrelatio nt oproductivity .

Theproductiv eperformanc eo fherd si slikel yt ob e influencedconsiderabl yb yits 'direc tenvironment .I nChapte r 2,paragraph s2 an d3 ,a ninfluenc eo fth eherd ,i.e .th eher d management,o nsevera lproductivit ytrait swa sidentified .Som e ofth easpect so fher dmanagemen ttha tma yb eo fsignificanc e areth ekraalin gpractices ,th emilkin gpractice san ddecision s relatedt oth eday-to-da ychoic eo fgrazing .

* Oneo fth eprim ereason sfo rkeepin gcattl ei nman y traditional systemsi nAfric ai sth eprovisio no fmanur e (Beerling,1991) . Themanur ei snormall yaccumulate db y

185 kraalingth ecattl eo nth efiel dwher ei ti st ob eapplied .B y shiftingth ekraa lever yfe wday sa laye ro fmanur ei ssprea d overth efield ,whic hi snormall yploughe dan dsowe do rplante d inth efollowin gwe tseason .Shiftin go fth ekraa li sdon eonc e every3 t o5 days ,dependin go nth eseason .I nth ewe tseaso n theperio d isshorter ,becaus eth esoi lbecome sto owe tan d dirtyfo rth eanimal st ospen dth enigh t (Baars,1989) .Ther e arecase si nwhic hth enecessit yo rdesir et ocollec tmanur e forcesth eanimal st oremai ni nth ekraal ,no tonl yfo rth e night,bu tals ofo rpar to fth eday .Thi smay ,especiall yi n thedr yseason ,compet ewit hgrazin gtim et oa nextent ,tha t thebod yconditio no fth eanimal scome sunde rpressure .Thi s obviouslywil lhav econsequence sfo rth eproductivit y interm s ofgrowth ,o fmil kyield ,fertility ,healt han dmortality .

Manurecollectio n isno talway spracticed .I ntranshuman t herdsofte nn okraa lshiftin gi sdon ewhe nth eanimal sgraz e thefloodplain ,sinc ethe yar eno tcampe do nth efield sdurin g thatperio d (Chapter2.1 ,tabl e1 ,fig .2) .I nth eBuloz i floodplainanimal sma yi nthos ecase sb etethere dt opole sb ya ropeattache dt oon eo fth efron tlegs .Also ,manurin gi s practiced lessfrequentl y inth esout ho fth eprovince .A reasonfo rthi si sdifficul tt odetermine .Som eexperiment s carriedou ti nth eMases eAgricultur eDevelopmen tAre aProjec t suggest,tha ta reaso nma ybe ,tha tth erain scom ewit hles s reliability inthi sare atha ni nth enort ho fth eprovince . Manuredmaiz egrow sfaster ,an dwit hbette ryields ,bu tseem s farmor esensitiv et odrough tcondition s (DeVries ,1989) .

Sincekraal shav et ob emobile ,the ynormall yconsis to f fencesmad eou to fbranches ,thor nbush ,o rpole swit h (barbed) wire,pu ti na squar eo rcircle .Ofte na ttime stha tmanurin g ispracticed ,a squar eshap ewil lb epreferred .Als oth ekraa l forth esucklin gcalves ,tha tar ekraale dseparatel y fromthei r mothera tnight ,i si nprincipl ebuil ti nth esam emanner . Sometimesver yyoun gcalve sdi eafte rheav yrain san di ti s commonknowledg eamon gman yo fth efarmers ,tha tth erain s causethi smortality ,undoubtedl ya sa resul to fchilling , sincecal fpen sar enormall yno troofe d (personalobservation) .

Another factortha tma ypla ya par ti nth ehealt ho f calvesis ,tha tshiftin go fcalf-pen si sdon eles sfrequentl y thanshiftin go fth ekraal sfo rth eadul tcattle ,becaus eth e contributiono fth ecalve st oth emanur edepositio ni sfairl y small.Thi scoul di nsom einstances ,especiall y intime so f rains,lea dt oth ecalf-pe nbecomin g filthy.Th epractic eo f regularlyremovin gmanur efro mth epe ni spracticall yunknown .

186 Especially ifth epe nremain smoist ,i ti slikel ytha t infectiveagent sar eabl et osurviv ean da build-u po f infectionoccurs .

Roofingcal fpen sma ysee mdesirable ,bu ti tha simportan t consequencestha thav et ob eadresse dwit hcare .Firstly , roofedpen swil lrequir emor elabou rinpu tt ob eshifted . Secondly,th esu nwil ln olonge rb eabl et odr you tth esoi li n thepen .Propagatin gth eus eo froofe dpen sshoul dtherefor eg o togetherwit hdevelopin ga conscienc efo rhygiene ,throug h litterprovisio nan dregula rremova lo fth emanure .

* Anotherfacto rofte nmentione da snegativel y influencing productivity,i nparticula rcal fsurvival ,i scompetitio nfo r milkbetwee ncal fan dman .Thi smeans ,tha ta sa resul to f milkingo fth ecows ,to olittl emil ki slef tfo rprope rgrowt h andhealth ydevelopmen to fth ecalf .I nth eWester nProvinc e twomai npractice sregardin gmilkin gca nb edistinguished .Cow s aremilke donl yonc ea day ,an dth epresenc eo fth ecal fi s essentialfo rth ereleas eo fmil kb yth edam .On eo fth e practicesis ,tha tcow sar emilke d inth emornin gbefor ebein g released forgrazing .Th ecalve sar ekraale dseparatel yfro m theirdams ,an dar erelease don eb yon ei nth emorning .The y areallowe dt osuckl efo ra fe wmoments ,an dthe nth eco wi s milked.Anothe rpractic ei st oreleas eth eanimal si nth e morningan dhav ethe mretur nt oth ekraa lfo rmilkin garoun d mid-day.Whethe rcompetitio n forth emil kplay sa rol ei nth e WesternProvinc ei squestionable .A si sshow ni nChapte r2.3. , onaverag ei ttake s8 0day safte rth ebirt ho fa cal fbefor e themothe ri smilke d forth efirs ttime .Furthermor eth eamoun t ofmil kderive d forhuma nconsumptio npe rco wpe rda yi ssmall , lesstha n1 litr epe rda y (122litre spe rlactation ,Besse lan d Daplyn,1977) .

* Anex t important factori nrelatio nt oproductivit yma yb e theday-to-da ychoic eo fth epastur et ob egrazed .A ver y thoroughknowledg eo fth equalit yo fth egrazin gpotentia lo f thedirec tenvironmen to fth evillag ewher eth eher di sbase d isrequire do fth eher dmanager .No tal lher dmanager swil l possesth enecessar y skillsi nequa lmeasure .Furthermor eth e possibilitieso fchoosin ggrazin gground sfo rones 'cattl ear e highlyvariable ,a si sth eseasona lvariet y inth efodde r quality.Her dmanager sshoul dhav eth epossibilit yt oassess , ina relativel yeas ymanner ,th equalit yo fth efodde ri nthei r environment.Thi sshoul dfirs to fal lb eaddresse dthroug h extension.Th eextensio neffort sshoul dprovid eth efarme rwit h simpleknowledg et ogai na nimpressio no fth eamoun to ffodde r

187 presento na particula rpasture ,and ,withi nth epossibilities , ofth enutritiv evalu eo fth egras san dherbage .Th efarme r shouldb etaugh tho wt oloo ka ta pasture ,ho wt ous ehi s senses.Factors ,tha tcoul db einvolve d injudgin gth e nutritivevalu eo ffodder ,coul dinclud eheigh tan ddensit yo f theforage ,an dth elea fconten ta srelate dt oth este m content.Anothe ruseful ltoo li sbod yconditio nscorin go fth e animals (Nicholsonan dSayers ,1987) .Man yfarmer salread ysee m totak eth ebod yconditio no fthei ranimal sint oaccoun ti n deciding,fo rexample ,whethe ra nanima li st ob emilke do r not. Iti sa facto ro fwhic hman yfarmer sar ealread yaware , buti ti sdesirable ,tha tfarmer sar eprovide dwit hth e possibility,throug hextension ,t ous ebod yconditio nscorin g asa too l indail ymanagement .

Itshoul db eborn ei nmind ,tha tharvestin g andstorag eo f foddercrop sfo rlate rus ei sa nunknow nphenomeno ni nth e WesternProvince .I ti slikel ytha tto olarg ea labou r investment isnecessar y inrelatio nt oth eadvantage stha tma y beexpecte d forthi st ob epractical .Providin gher dmanager s withknowledg et oasses sth equalit yo fthei rgrazin ggrounds , supportingth echoic eo fpastures ,i sa prim eextensio ntask .

* Acomplicatin g factori nth emanagemen to fgrazin g resourcesi sth eavailabilit y andpositio no fherdsmen . Gluckman (1973)an dVa nHor n (1977)describe dth econsequence s of labourmigratio nfo rth estandar do fagricultur ei nth e WesternProvince .Apar tfro mreducin gth esurfac eo fth earabl e landi nth eprovince ,i tals oresulte d ina shortag eo f herdsment oloo kafte rth eanimals .Anothe rcaus ewas ,tha t youngboy sspen dmor etim ea tschoo ltha nbefore .Th eresul t mayhav ebeen ,tha tth eabilitie sfo rherdin gcattl eo fthos e stillavailabl efo rth ejo bwer eles stha nbefore .I tbecam e forexampl eincreasingl ydifficul tt osen dherdsme nawa ydurin g theflood st oth ebes tgrazin ggrounds .Th epositio nan dsocia l statuso fherdsme nmus thav esuffere d fromthi sdevelopment .A t presentth esocia lstatu so fherdsme ni slo w (Beerling,1986) . Thewage sar eals oquit elow ,an di ti stherefor edifficul tt o attractskille dpeopl efo rth ejob .Ther ei sa clea r indication,tha ti nsituation swher eth eher dmanage ro rhi s direct familyar ethemselve sresponsibl efo rherdin gth e cattle,th eproductiv eperformanc ei spositivel yinfluenced .

* Burningo fgrasslan dma yals ocomplicat epastur e management.I ti softe npractice dt orejuvenat eth evegetation . Matthewman (1980)mention sindiscriminat eburnin ga sa seriou s threatt oth enutritiona lstatu so fcattle .Burnin go fth e

188 grassi softe ndon efo rreason scompletel ydifferen tfro m rejuvenationo fth evegetatio nwit hth eobjec tt oimprov eth e qualityo fth efodde rfo rth eanimal s (Frost,1992) . Itma yb e donefo rexampl et odeplet ecoverag efo rgame ,i norde rt o facilitatehunting .Th eForestr yDepartmen tpractice searl ydr y seasonburnin gt opreven tdestructiv ebus hfire slate ri nth e season.I nth efloo dplain sburnin gi softe npractice d inorde r toreduc eundergrowt hwhe nth eplain sar eflooded ,s otha t fishingbecome seasier .Lastly ,especiall ydirectl yaroun d villages,burnin g ispractice dt oreduc ecoverag efo rpossibl y dangerousvermi nan dsnakes .Thoug hthes ereason sma yofte nb e rational inthemselves ,the yar edestructiv ei nrelatio nt oth e provisiono ffodde rfo rth ecattle .Therefore ,i norde rt omee t demandso fal luser so fth erangelands ,a nintegrate dapproac h tomanagemen to fpasture si sneeded .

Ifth eobjec ti st oimprov eth equalit yo fth efodder ,th e timingo fth eburnin g isessential .Ther emus tb ea tleas tsom e timeo fth egrowin gseaso nlef tt oallo wfo rregrowth ,o rth e burning shouldb edon eonl yshortl yafte rth ene wrain shav e started.Th etimin go fth eburnin gpractice sdiscusse dher e bearsn orelatio nt othis ,an dar etherefore ,fro mth epoin to f viewo ffodde rprovisio nt ob econsidere da shighl y undesirable.I nvie wo fth eimportanc eo fcattl efo rth erura l economyo fth eprovinc e (Mwafulirwaan dMoll ,1991 )i tseem s necessaryt oformulat eprioritie si nthi smatter .I tshoul d howeverb eborn ei nmind ,tha tburnin gpractice sma yb ecarrie d out, outo fnecessity ,b ypeopl etha td ono tow nan ycattl ean d aretherefor erelian ton ,fo rexample ,fishin go rhunting . Utmostcar ei nformulatin gthes eprioritie si stherefor e necessary.I nlan dus eplannin gth eintegrate dapproac h mentionedearlie rshoul db eexpressed ,an dth epositio no f theseothe ruser so fth egrazin grang eshoul dpla ya role .

Iti spossibl et oinfluenc eher dmanagemen tpractice s throughextensio n (Vijfhuizenan dMumbuna ,1990) . Iti s essential,tha tth eextensio nmessage sar eaime da tloca l solutions.Th eextensionis t shouldstan dclos et oth elivestoc k ownersan dshoul dunderstan dthei rparticula rneeds .A t present,extensio ni sstil lto omuc htransferre d fromstandar d information.Thi sinformatio ni softe nto ogenera li nnatur e andto olittl eapplicabl et oth esituatio no findividua lcattl e owners.Also ,th eimportan tinfluenc eo fsocio-economi cfactor s shouldb erecognise d inextension .

Thefac ttha tther ei sa ninfluenc eo fth eher dmanagemen t onproductivity ,shoul dmak ei tpossibl et oidentif yelement s

189 fromth eday-to-da ymanagemen to findividua lherd stha t determineth eleve lo fth eproductivity .Thes eelement sma y include:

- themomen ti nth eda ytha tcow sar emilked , thecriteri ao nwhic hth eher dmanage rdecide swhic hcow s tomilk ,an dwhe nt ostart , - themomen ti nth eda ytha tth eherd sar erelease dfo r grazingan dar etake nbac kt oth ekraal , thepresenc eo rabsenc eo fherdsme nan dthei rrelatio nt o theher dmanager ,an dth epar tthe ypla yi ndeterminin g whichgrazin gground st ouse , - thecriteri ath eher dmanage ruse st odetermin ewhic h pasturest ouse , themomen ti nth eda yth eanimal sar etake nt odrink , theway si nwhic hcalve sar etake ncar eof , kraalshiftin gpractice s (e.g.frequency )fo rth ekraa l foradul tanimal sa swel la sth ecal fpen , amounto fspac epe ranima li nth ekraal , breedingpractice s (choiceo fbulls ,servicin g supervision).

A studyint othes easpect scoul dals oinclud easpect ssuc ha s theownershi pdivisio ni nth eherd ,th enumbe ro fowner si nth e herdan dthei rrelatio nt oth eher dmanager .Suc ha neffor tma y deliverth ebackgroun d informationfo rextensio nmessage stha t areoptimall yadapte dt oth eloca lsituation .A syste mo f assessmento findividua lher dperformanc ei sneede dfo rthis . Theher dmonitorin g systema si twa suse di nth estud ycoul db e used forth eprocessin go fth eproductivit ydata .I nth ecours e ofth eher dmonitorin gprogramm ea compute rapplicatio nwa s developedtha tcalculate ssom eproductivit ytrait si n individualherd so ri nan ytyp eo fgrou po fherds .Thi s applicationwa suse di nthi sthesi sonl yt ocalculat eth e averageher dcompositio npresente d inChapte r2 .I tcoul db ea n instrumentt oevaluat emanagemen taspect so fproductivity , although itdoe sno tallo wfo rdirec tstatistica lanalysis . Schoonmane tal . (1992)gav ea proposa lfo ra stud yint oth e relationbetwee nbot htechnica lan dsocio-economi c factorsan d productivityo findividua lherd saime da tdevelopin grelevan t extension.

5.3. Environmentalfactor si nrelatio nt oproductivity .

Chapter2.2 .an d2. 3 show,tha tinfluence so fsevera l environmental factorso nproductivit ytrait scoul db e identified.Seasona linfluence swer eclearl ypresen t inth e

190 girthassessmen tan dcoul dals ob efoun di nsom eo fth e lactationinterval san di na seasona lcalvin gpattern .Climati c influences,i.e .i nthi srespec tchiefl yth einfluence so f annuallyvaryin grainfall ,seeme dt ob epresen ti nsom etraits , identifiedb ycomparin gth evalue so fthes etrait si ntw o consecutiveperiod so fon eyea r (periodI an dperio dII) . However,th edifference sfoun di nthi smanne rshoul db e regarded asindicative .Ther ewer edifference sbetwee nth etw o periodsi nth eamoun to frainfall ,bu ti twoul dprobabl yb e bettert omak ea compariso no fmor eon eyea rperiods .

* Betweenth eGrazin gManagemen tSystem s (Jeanesan dBaars , 1990)als odifference si nsevera ltrait scoul db efound .Th e descriptionso fth eGrazin gManagemen tSystem sar eprobabl y ratherrough ,bu ta carefu lconclusio nma ybe ,tha tth e different systemsd oexer tdifferen t influenceso n productivity.I na her dperformanc estud y (Schoonmane tal. , 1992),aime da tidentifyin gmor edetaile d influencesa ther d level,aspect srelate dt oth egrazin genvironmen twoul d probablyhav et ob etake nint oaccoun ti na mor edetaille d manner.Thi sma y forexampl einclud eth edistance scovere deac h dayfo rgrazin gan dwatering ,whic hma ydiffe rconsiderabl ype r herd.Suc ha stud yi slikel yt oproduc eusefu ldescriptiv e results.I tma yb eappropriat et ous ethes edescriptiv eresult s inris kanalysi san dris kmodellin gmethods ,bearin g inmin d thepossibilitie san drestriction si nth edesig no fth estudy . Thesemethod sprovid epossibilitie st oasses sth erelativ e importanceo fth easpect sinvolve d indail ymanagemen t (Cohrssenan dCovello ,1989) .

* Taking intoaccoun tth efac ttha tanimal sdyin go rbein g slaughtered inemergenc youtnumbe rth eanimal sbein gsold , mortalityca nb econsidere da son eo fth econstraint s identified.Especiall yamon gcalve sth emortalit y seemst ob e high.Th emortalit y ison eo fth etraits ,fo rwhic h environmental andclimati cfactors ,bu ti nsevera linstance s alsoinfluence so fth emanagemen t inth eher dwer eidentified .

* Longcalvin g intervalsma yb econsidere danothe r constraint.Ag ea tfirs tcalvin gwa sno tstatisticall y evaluated atlengt hi nthi sthesis ,bu tsinc eth eaverag e rangesaroun d3 t o4 year si tcoul db eargue dtha t iti sals oa productivitytrai twort hgivin gattentio nto .Mor eso ,sinc e thevariet y inage so ffirs tcalvin gi squit elarge .Thi si s alsotru efo rth ecalvin g interval.Thi swoul dsuggest ,tha t therei sroo mfo rimprovemen to fthes etraits .Th edifficult y withthes etrait showeve ris ,tha tthei reffec ti nth esens eo f

191 performancei sles sclea rt ofarmer stha nfo rinstanc e mortality.Ther ewer en ofarmer sinvolve d inth estud ywh o practiced somemean so foestru sdetectio no rbreedin gcontrol . Inal lcase sbulls ,runnin gfreel ywit hth eherd ,sire dth e cowsi nhea ti na nuncontrolle dmanner .This ,togethe rwit hth e apparent feelingtha tgestatio ncoul dhardl yb einfluenced , wouldprobabl ycaus ethi sconstrain tt ob efel tdifferentl yb y thefarmer sthemselves .

* Thegirt hmeasuremen twa schose nfo rth eevaluatio no f growth,becaus eo fit seas eo fus ei nth efield .Growt hi si n itselfno ta ver y importanteconomi cfactor ,becaus ehardl yan y traditional livestockkeepe rinvest si ngrowth ,a tleas tno ti n theWester nProvince .Practicall yal llivestoc ki sgraze do n naturalgrassland ,an dver yfew ,i fan ylivestoc kowner sus e supplemento ffeedstuffs .Tw omai nreason sfo rno tinvestin gi n growthare ,tha tth elos so fweigh ti nth edr yperiod scanno t becompensate d fori na neconomicall y sensibleway ,an dtha t thelivestoc k isno tfattene d fora specifi c (optimal)ag eo r weight.Sale so fanimal sar eno tth emai neconomi cai mo fth e herdmanager .Animal swil lb esol dwhe n (immediate)cas hneed s arise,an dth eher dmanage rwil lsel lanimal stha th eca n spare,i nth ecas eo fcattl eusuall yol doxe no rcows .Littl e orn odirec tgai ni stherefor et ob ederive d frominvestment s ingrowth .Th eanimal stha tar enormall ychose nt ob esol d willhav eattaine dthei rweigh ti nth echeapes tpossibl eway , bygrazin gth enatura lgrass .

Growthis ,however ,o findirec timportance ;animal stha t growwel lan dar ei ngoo dbod yconditio nar eusuall yhealthy , areles slikel yt odi eo rb eattacke db ydiseas ean dwil lb e fertile (Ogink,1993) .Goo dgrowt hi nth ewe tseaso nwil lhel p theanima lt ocop ewit hth eadversitie so fth edr yseason .Fo r theevaluatio no fproductivit yperformanc ei ti stherefor ea usefultrait .

Bodyconditio nscorin gwa sals odon edurin geac hthree - monthlyvisit .I twa sconsidere d asbein ga tleas ta simportan t asgrowth .I tappeare dhowever ,tha ti tcoul dno tb euse dfo r statisticalevaluation ,becaus ether ewa sto olarg ea bia so f theobserver ,i nspit eo fth efac ttha ta mor eo rles s standardisedbod yconditio nevaluatio nschedul ewa sused .A s alreadystated ,bod yconditio nscorin gi sa goo dtoo lfo rth e herdmanager ,t osuppor tday-to-da ydecision so nhi smanagemen t ofbot hth eher dan dth eindividua lanimal ,especiall y ifonl y oneobserve ri sinvolve d inth escorin g (Nicholsonan dSayers , 1987).A ssuch ,attentio nshoul db egive nt oi ti nterm so f

192 extension.

Itha sbecom ever yclea ri nth ecours eo fth eher d monitoring study,tha tampl eargument swer eprovide d forth e importanceo fa nintegrate dveterinar yan dzootechnica l approacht oresearc han dextensio ni nth efiel do fproductivit y improvement.

5.4. Parasitesi nrelatio nt oproductivity .

Asshow ni nChapte r4.1 .an d4.2. ,hardl yan yadvantag eo f regulartreatmen tagains tintestina lparasite so rliverfluke s couldb edetected ,base do nthi sstud ydesign .I nChapte r4.3 . someattentio nwa sgive nt opossibl ecause sfo rthi sa sa resulto fth etria ldesign .Th efac ttha tfiel dtrial swer e usedher ema yhav epose dsom eproblem sregardin gth e organisationalaspect so fth etria lan dpossibl yo nth e reliabilityan drepeatability .Thes eissue so fdilemm abetwee n scientific studydesig nrequirement san dlogisti c feasibilities havebee nextensivel yaddresse d inrecen tliteratur e (Noordhuizene tal. , 1993).

Nevertheless,fiel dtrial sca npotentiall ygiv emor e informationtha n (more,possibl yeve nto omuc hconditioned )on - stationtrials .Environmenta lan dmanagemen taspect sca n influenceth eoveral leffec to ftreatmen tagains tparasites . Infectiono fth epasture ,an dgrazin gmanagemen tdecision sar e someo fthes easpects ,a si sth einfluenc eo fth equalit yo f thephysica lenvironmen to nth ecapabilit yo fth eanimal st o copewit hparasiti c infections.Th epracticabilit yo fth e resultsfo rth edevelopmen tprojec ti nwhic hth esurve yi s carriedout ,determine swhethe ro rno tconcession si nth e reliabilityan drepeatabilit yo fth eresult sca nb etolerated . Someo fth efactors ,involve d inbot hth eproductivit ystud y andi nth einterventio nstudy ,relate dt obot hth emanagemen t andth eenvironment ,di dsho wth esam epatter no finfluenc ei n bothstudies .Thi ssuggest stha tth erepeatabilit yo fthes e resultsma yb equit egood .Th einfluenc eo ftreatment si si n anycas eno tdramatic .

Assumingtha tth eresult sar ereliabl eenoug ht oconclud e thatroutin etreatment sagains thelminth san dliverfluke sar e notviable ,som econsideratio nshoul db egive nt oth ereason s forth efac ttha tthes egroup so fparasite sapparentl yd ono t causeinsuperabl eproblems .A swa sstate d inChapte r4 ,th e numberso fintestina lhelmint hegg sfoun d inth esample stake n inth ecours eo fth estud ywer elow ,i fcompare dwit hEP 6

193 valuesfoun di nliterature .Thi sma ywel lmea ntha tth e infectionpressur ei si nfac tmoderate ,thoug hacut eclinica l caseso fhelminthosi sar esee na ttimes .Thes ecase sar e generally isolatedcase si nyoun ganimals ,mostl yi nth esecon d halfo fth ewe tseason .I tma yb epossibl etha ta predisposin g suboptimalconditio n (e.g.becaus eo fanothe rdisease , insufficient fodderquantit yo rquality ,insufficien tgrazin g byth eanima la sa resul to flameness )play sa part .Becaus e thecase sar eofte npresente d ina relativel y advancedstage , theunderlyin gcause sar erarely ,i fever ,identified .O nth e otherhand ,lo wEPG' sno tnecessaril ymea ntha tth einfectio n ratei sals olow .Th eleve lo fth eEP Gi sno talway srelate dt o theseriousnes so fth eclinica lproble m (Parentan dSamb , 1984).

Thepresenc eo fliverfluk eegg scoul dhardl yeve rb e demonstrated,althoug h fromow nobservation sa swel la sfro m literature (Jorgensenan dKamukwai ,1977 ,Silangwa ,1972 ,1973 ) iti sclea rtha tliverfluke sar eabundantl ypresen ti nth e floodplainarea so fth eprovince .Acut efascioliasi si s sometimesseen ,especiall y inth elat edr yseason ,whe nth e animalsi nrelativel ypoo rconditio nconcentrat eo nth e floodplains,a swa sals osee nb yBabalol aan dSchillhor nva n Veen (1976)i nNigeria .

Inth ecas eo fth ehelmint h infectionsa relativel ylo w infectionpressur ema yhav ebee npresent .A sregard sth e liverflukeinfection si tca nhardl yb eassume dtha tthi si s alsoth ecase ,i nspit eo fth efac ttha tn oegg shav ebee n found.Still ,treatmen tdi dno tgiv ea measurabl eimprovemen t ofth eproductivity .I nthi scas eth eenvironmen tma yb eo f greater importancetha nth epresenc eo fth eflukes .Th e positiveeffect so ftreatmen tma yhav ebee nmaske db y variationsi nrang econdition san dfodde rquality .I nth ewe t seasoni nparticular ,th eadvers eeffect so finfection sma yb e maskedb yth ebette rfodde rquality .Sinc eth eanimal sgraz e awayfro mth efloodplai nfo rpar to fth ewe tseaso nre infectioni sprobabl yals oprevented ,whil eth eanimal sma yb e capableo friddin gthemselve sfro mth efluke s (Kendallan d Parfitt,1975) .Th emaskin geffec to fth eenvironmen ti s mentionedb yOakle ye tal . (1979). Pourgroup so f1 5Britis h Friesiancalve swer euse d inth estudy .Tw ogroup swer e artificially infectedwit hmetacercariae .On euninfecte dgrou p (group1 )wa sfe dt ogai n68 0gr .pe rday ,on eo fth einfecte d groups (group2 )wa sals ofe dt ogai n68 0gr .pe rday .Th e other infectedgrou p (group3 )wa sfe dth esam equantit yo f fodderconsume db ygrou p1 ,an dth esecon duninfecte dgrou p

194 (group4 )wa sfe dt ogai nth esam eamoun to fweigh tpe rda ya s group3 .Infectio nprove dt ohav ea limitin geffec to ngrowt h ratean dfoo dconversion .Th eeffec to ngrowt hwa smaske di n theanimal so na lowe rplan eo fnutritio n (groups3 an d4 compared),bu tno ttha to fth efoo dconversion .Simpso ne tal . (1985), however,sa wclea radvantage so ftreatmen ti n particular inperiod stha tfoo dstres si spresent .Thi s conclusionwa sdraw nfro mcalculations ,carrie dou to nth e basiso festimate so fdamag edon eb yliverflukes ,give nb y veterinaryan dproductio nspecialist si nFlorida ,USA .Th e estimateswer edivide d intw olevels ,lo wan dhigh ,wit hth e assumptiontha tth eactua lvalue swoul dfal lwithi nthos e limits.

Apartfro mth elo winfectio npressur eo fth eintestina l helminths,i ti spossibl etha trapi dre-infectio nafte r treatmentannul sth eeffec to ftreatmen t (Anonymus,1979) .I f thisi sth ecase ,eve na nintensiv eschedul ea swa sfollowe di n thetrials ,especiall ydurin gth ewe tseason ,i sapparentl yno t ablet oproduc efavourabl eresults .Becaus eo fth ecommuna lus e ofgrazin glands ,i ti sa nillusio nt othink ,tha tgrazin g rotationschemes ,t opreven tre-infection ,combine dwit h supportivetreatments ,ca nb eintroduce d inth etraditiona l systemo fth eWester nProvince .

Theconclusio n fromth eresult so fth etrial smus tb etha t forth etim ebein ganthelminti can dflukicid etreatment sshoul d berestricte dt oclinica lmanifestation so fth ediseases . Improvemento fproductivit y ismor elikel yt ob eattaine db y improvingth emanagemen tskill so fth elivestoc kowners ,an d thecapabilit yt ocop ewit hth especifi ccharacteristic so fal l theirresources .

5.5.Economi can dsocio-economi caspect so fcattl ekeepin gi n relationt oproductivity .

Inth ecultur ean dsocio-economi c structureso fth epeopl e ofth eWester nProvinc ecattl ehav eplaye da dominan tpar tfo r aver y longperio d (Roberts,1976) . Socio-economic characteristicso fth ecattl ekeepin gpractic ei nth eprovinc e undoubtedly arerelate dt oth ewa ymanagemen tdecision sar e reached (Wood,1988) .Thes esocio-economi c characteristics includefo rinstanc eownershi po findividua lanimal si n relationt oth eownershi po fherds ,an dmanagemen t responsibility forindividua lanimal san dherds .Managemen t decisionsmay ,i nthei rturn ,b eo fimportanc efo rth e productivityo fth eherds .Thes emanagemen tdecision spertai n

195 today-to-da ydecision so nwha tpasture st ograze ,whic hcow s tomil kan da twha tmoment ,whe nt oreleas eherd sfo rgrazin g andwhe nt otak ethe m forwatering ,an ddecision so ndisposa l andpurchase .

Iflivestoc kdevelopmen teffort si ntraditiona lAfrica n livestock systemsai ma timprovemen to fth eproductivity ,o ra t solvingproductivit yconstraints ,i ti so fimportanc et oasses s asmuc ha spossibl ewher esocia lan dcultura lstructure sma yb e relatedt oth eproductivit yo fanimals .Mor eso ,sinc ethes e structuresma ydetermin et oa considerabl eexten twhethe ro r notfarmer sar eabl et ofollo wdevelopmen t recommendations (Dickiean dO'Rourke , 1984).Dicki ean dO'Rourk edistinguished , amongothers ,th efollowin gpolitical-economi c andsocia l factorsa sconstraint st olivestoc kproduction :

1 agriculturaldemand s (inparticula rcompetitio nfo r grazingland ) 2 tradecondition s (tradeinfrastructur ean dpricin g development) 3 customsconcernin ganima lhusbandr y (ownershipan d responsibility) 4 traditional landus e (communalgrazing ,grazin grights )

5.5.1. Agriculturaldemands .

Inth eWester nProvinc eo fZambia ,demand so fagricultur e areno ta rea lconstrain tt olivestoc kproduction .Th eare ao f arablelan di sb yn omean scompetitiv et oavailabl egrazin g land (VanHorn ,1977) . Infact ,agricultur ean danima l husbandryar ecomplementar yt oeac hother .Cattl ei s indispensible inlarg earea so fth eprovinc efo rth eprovisio n ofdraugh tpowe ran dmanur e (Beerling,1991) .

5.5.2. Tradeconditions .

Tradecondition sd opla ya ke yrol ei nth eWester n Province (DeRooi jan dWood ,1990) .A sa resul to flogisti c difficulties,cattl epurchase sar eno tequall ydistribute dove r theprovince ,an dprice sar einfluence dmarkedly .I nth emor e remoteareas ,especiall ywes to fth eZambez irive ran dtoward s theAngola nborder ,price so fcattl ear econsiderabl y lower thani nth evicinit yo fth elarge rroad seas to fth eZambezi . Mosto fth ecattl esol di nth eprovinc ei stransporte dt o Lusaka,th ecapita lo fZambia ,t oLivingston eo rt oNdol afo r slaughter.D eRooi jan dWoo d (1990)strongl ypleade d foracces s ofthir dpartie st oth eabbatoi ri nMongu ,th emai ntow no fth e

196 WesternProvince .Thi sabbatoi ri soperatin g farbelo wits ' capacitya tpresent .A caus ema ybe ,tha tth ebuyer soperatin g inth eservic eo fth eZambi aCol dStorag eCorporation ,th e ownerso fth eabbatoir ,d ono thav eenoug hfreedo mo f bargaining.A sa resul to fthis ,cattl ebuyer sfro mothe r origin,ofte nprivat etraders ,hav ea nadvantag e inth efield . Theconsequenc eis ,tha ta larg econtingen to fanimal sleav e theprovinc ealive ,whil ei twoul dhav ebenefitte dth eeconom y ofth eprovinc ei nvariou sways ,i fth eanimal scoul dhav ebee n madet ovalu ewithi nth eWester nProvince .No tonl yth edirec t earningso fth ecattl eseller scoul db eimproved ,sinc e transportcost sar elower ,bu tth eemploymen tpossibilitie si n theprovinc ecoul dals obenefit .A si nman yrura l (andurban ) areasi nAfrica ,ther ei sa grea tshortag eo fforma l employment,an di ti swel limaginabl ethat ,i fth e possibilitiest oslaughte ranimal swithi nth eprovinc ewoul db e improved,i twoul dbecom eincreasingl y interestingt ose tu p meatan dby-product sprocessin g industriesi nth eprovince .I n thismanner ,th eeconom yo fth ewhol eprovinc ewoul dbenefi t fromthi sspin-of feffec to flivestoc kdevelopmen t (Mellor, 1986).

5.5.3. Customsconcernin ganima lhusbandry .

Multipleownershi pan dtransfer so fanimal sbetwee nherd s (Beerling,1986 ,Beerling ,1991 )ar esom ecustom sconcernin g animalhusbandr ytha tca nb ementione da sinfluentia lfactor s inanima lproduction .Th eproportiona l importanceo fcattl e transfersfo rvariou sreason sa swel la sth evariation si n ownershipinvolvemen t inth eherd swa sillustrate d inChapte r 2.4.I nthi sstud yn oattemp tha sbee nmad et oevaluat eth e productiveperformanc ei nrelatio nt oth etransfe rrat eo rth e numbero fowner sinvolve d inth eherds .I tprove dt ob e impossiblefo rth efollowin greasons .Includin gthe mi nth e modelsa sindependen tvariable sprove dver ydifficult . Especiallyregardin gownership ,th evariet ywa sto obig . Classificationwa sals ono tver ypractical ,sinc eapar tfro m thenumbe ro fowners ,als oth erelatio no fth eowner swit hth e herdmanage rshoul db eweighed .

Thenumbe ro fowner sinvolve d inan yher drange dbetwee n1 andmor etha n2 5 (Chapter 2.4).Generall yon eperso ni s ultimatelyresponsibl efo rday-to-da ydecision sconcernin gth e herd.Thi sher dmanage rwil lhoweve rno tb eabl et omak eal l possibledecision sregardin g individualanimal s (Beerling, 1986).Th edecisio nmakin gproces si nth eherd si sstil l subjecto fresearc h ina Livestoc kDevelopmen tProjec t (De

197 Rooijan dWood ,1990) .Som efield st owhic hdecisio nmakin g concerning individualanimal sma ypertai nar esale san d financialinvestment ,fo rexampl ei nth epurchas eo fdrugs .

Theowner sinvolve d inan yher dmostl ybelon gt oth e direct familyo fth eher dmanager ,wh oi softe na tth esam e timehea do fth efamily .Decision st osel lanimal swil l probablyb emad eb yth eowne ro fth eparticula ranimal ,bu t willofte nno tb eeffectuate dwithou tconsulting ,no rwithou t theconsen to fth eher dmanager .I tshoul db enoted ,tha tsal e ofanimal susuall ycome su ponl ywhe na nacut ecas hrequiremen t necessitatesthi s (Beerling,1986) . Iti sobvious ,tha tsuc h far-reachingdecision sa sreducin gth efamil yherd ,shoul db e madeafte rcarefu lconsideration .Give nth ecircumstances ,thi s isabsolutel ycommo nsense .Sinc esale so fanimal snormall y occurfo rspecifi cfinancia lpurposes ,th erevenu ewil lno tb e readillyavailabl efo rth eadvancemen to fth eher ditself .A s such,i ti sa tleas tquestionabl ewhethe rthi spractic eshoul d beregarde da sa rea lconstrain tt oproduction .Thi ssituatio n maychang ei fcost-recover ymeasure sfo rth eservice srendere d byth eDepartmen to fVeterinar yan dTsets eContro lservice s (Chizyukae tal. , 1987),an dprobabl yb yothe rinstitution s (e.g. extensionservices) ,ar eeffectuated .Th econsequenc ema y betha tsom efor mo ffinancia linpu tint oth eher dha st ob e found.

Transferso fanimal sbetwee nherds ,occurrin g ina frequencyo fapproximatel y 10% o fth enumbe ro fanimal spe r herdpe ryea r (Chapter2.4) ,ma yb eanothe rfacto rcomplicatin g thedesig no fcost-recover ymeasure s (DeRooi jan dWood ,1990) . Placinganimal sunde rth ecar eo fother simplie sa transfe ro f responsibility.Th eexten tt owhic hresponsibilit y istake nu p isagai nlikel yt oinfluenc edecisio nmakin gregardin gth e individualanimal .Thi sma yb eclosel yrelate dt oth epurpos e oftransferrin ganimal s (Chapter2.4) .I fa her dmanage r borrowsanimals ,fo rexampl efo rmanure ,draugh tpowe ro rmilk , itma yb eargue dtha th ewil lnecessaril yhav ea highe rleve l ofinteres ti nth ehealt ho fthes eanimals ,tha ni fcattl ei s placedunde rhi scar eb yothers ,i nwhic hsituatio nth e originalowne ro fth eanimal si sth eprincipl ebeneficiar yo f thearrangement .

Anotherfacto rrelate dt ocattl etransfer stha tma yhav e consequencesfo rproductivity ,is ,tha ttransfer sma y constitutehealt hhazards .I tma ybe ,tha tcertai ninfectiou s diseasesar eintroduce dan dsprea dthroug htransfer so f animals,a swa sals ostate d inth ediscussio no fChapte r2.4 .

198 Iti swel lpossible ,tha tfo rexampl eth esprea do fBlackle g (Clostridiumchauvoe iinfection )ma yb elinke dwit htransfer s ofbridepric ecattl e (personalobservation) .Normally , relativelyyoun ganimal sar echose nfo rthis .Th ediseas e occursmostl y inanimal sbetwee n6 month san dtw oyear so fag e (Selman,1981) ,an dinfecte danimal sma ysprea di twhe n transferreddurin gth eincubatio nperiod .

Anotherdiseas eo fwhic hth eclinica loccurrenc ema yb e associatedwit htransfers ,o rrathe rwit htransport so f animals,i sHaemorrhagi cSepticaemi a (associatedwit h Pasteurellamultocid ainfection) .I nth eWester nProvinc efoci , fromwhic hHaemorrhagi cSepticaemi aspread speriodically ,wer e associatedwit hsite swher econcentration so fanimal soccurre d regularly.Thes esite swer eplace swher etrad ecattl ecrosse d theZambez irive ro nthei rwa yfro mth ewes to fth eprovinc et o theabbatoir .I nth ecas eo fthi sdiseas eth enumber so f animalso ntransfe r isofte nconsiderable .I ntransfer sbetwee n herdsofte nonl yon eo ronl ya fe wanimal sar etake nfro mon e herdt oth eother .Determinin gwhethe rthes etransfer sar e important inth ebehaviou ro fdisease si ngenera lterm sma yb e difficultunde rfiel dconditions .Simulatio nmodellin gan dris k assessmentprocedure so nth ebasi so ffiel dinformatio no nth e locationo fclinica lcase so routbreak san dtransfer scoul db e anappropriat etoo lt ostud yth erisk so fintroductio nan d spread.

Whiletransfer sma yconstitut ehealt hrisks ,on eo fth e aimso ftransferrin gcattl et oherd so fother sis ,t osprea d theris ko floosin ganimal sthroug hepidemi c (e.g.Heamorrhagi c Septicaemia),o rendemi c (e.g.trypanosomiasis )diseases .Thi s seemsa contradiction ,bu ti tdoe sshow ,tha ta clea ran dwel l reasonedrational ei sth ebasi so fdecision st otransfe r animals.Benefittin g fromgoo dgrazin go rfro mprim ebreedin g bullsar elikewis esoun dmanagemen treason stha tseemingl yar e ofbigge rimportanc etha nth esuppose dhazard st ohealth . Modellingma yagai nb eabl et oprovid epossibilitie st o quantifyth erisk so ftransfer san dweighin gthe magains tth e benefitsresultin gfro mthem .

Aswa sstated ,quantificatio no fth einfluenc eo f ownershipan dtransfer so nproductivit ywa sno tcarrie dou ti n thisstudy .I na nindividua lher dperformanc estud ywit hth e aimo fderivin gpracticall yusefu lextensio ninformation ,i t mayhoweve rb eo fimportanc et oinclud ethes efactor si nth e assessment.Nevertheless ,i tshoul db eborn ei nmind ,tha t factorssuc ha sthes eshoul db eregarde dpredominantl ya s

199 conditionalaspects ,rathe rtha nvariable stha tca nb e influencedt oa considerabl eextent .

5.5.4. Traditionallan duse .

Themai ncharacteristi co ftraditiona l landus ei s communalus eo fgrazin gresources .N olivestoc ko rher downe r hasprivat eright so rtitl edeed st ocertai ndelineate d stretcheso fland .Thi si sals otru efo rlan duse dfo r cultivation.This ,however ,doe sb yn omean smean ,tha tn o orderwhatsoeve runderlie sth eus eo fth eland .Gluckma n (1973) showsthroug hhi sreport so ncour tcase si nth eloca lan droya l courtsi nth eWester nProvince ,tha ta comple xo farrangement s andforma lassignmen to f landus eright sar ei nforce .Thi sma y bemor estric tfo rcultivate d landtha nfo rgrazin g land,bu t iti scommo nknowledge ,tha ti fa her dmanage rwant st o permanently shifthi sher dt oa ne wsettlemen tarea ,h ewil l havet oacquir eth epermissio no fth eloca lchief sresponsibl e forth etraditiona lgovernmen t inth earea .

Sincen oindividua lownershi pright sar ei nforce ,i tca n hardlyb eexpecte dtha tinvestmen t inimprovemen to fth e grazingresourc etake splace .Sinc eth eclimati can dsoi l fertility factorsar efa rfro mstimulatin g inthi srespect ,i t isno tlikel ytha tthi swoul db eimportantl ydifferen ti f individualtitl edeed st olan ddi dexist .Improvemen to fth e useo fth egrazin gresourc ecanno tli ei nprivatisin g landownership.Th eSocio-Economi cAnalysi sTea man dth e RangelandManagemen tTea m inth eWester nProvinc e (1992) concluded,i na stud ycarrie dou tt oprovid einformatio nfo r policymaking ,a swel la st oidentif yextensio nrequirements , thatgrazin gmanagemen tpractice san dth eus eo ffodde ran d waterresource sar erationa lan defficient ,give nth e circumstances inth eprovince .Thoug hconsiderabl estretche so f potentialgrazin glan dremai nunuse d (Socio-EconomicAnalysi s teaman dRangelan dManagemen tTeam ,1992) ,thi ssituatio n prevailsfo rsoun dreasons .Ofte nlac ko fprope rwaterin g pointsi sth edirec tcaus e (Jeanesan dBaars ,1990) .

Landus eplannin gi sconsidere da nimportan t issuei n livestockdevelopmen t (VanRootselaa ran dWood ,1990) .Researc h intostructure stha tunderli ecommuna llan dus ei stherefor e important.Thi si simportan t forpolic ymakin gi nlivestoc k production,bu tals ot okno who wt odirec textensio nmessages . Dickiean dO'Rourk e (1984)mentione dtha trang emanagemen t advisorsshoul dbas ethei radvic eo na necologically , economically,a swel la so na culturall y soundbasis .A s

200 regardsthi scultura laspect ,the ycite da Maasa ielder ,t o illustrateth eimportanc eo fbein gwel lawar eo fth eloca l socialsituatio nregardin ggrazin glan duse .Thi sman ,chairma n ofa livestoc kvillag ei nTanzania ,remarke dtha tgoo d techniciansperforme dpoorl ybecaus ethe ydi dno tunderstoo d thatth eelder sar eth edecidin gpower .I fther ei sn o awarenesso fthi ssituation ,th emessag ewil lneve rcom e across.Th estud yint otraditiona lgrazin gmanagemen tb yth e Socio-EconomicAnalysi sTea man dth eRangelan dManagemen tTea m (1992)wa saime da tdeterminin gth estructure spertainin gt o thedecisio nproces so nth eus eo fgrazin glan di nth eWester n Province.

Whilei twoul dsee mquit epossibl et oalte rconstraint st o productionresultin g fromth ecattl etrad epractices ,thi si s quitedifferen t fromfactor stha tar epredominantl y culturally andsociologicall ydetermined .I tcoul db eargued ,tha ti fa resulto f livestockdevelopmen teffort saime da timprovin g veterinary servicesis ,tha trisk so fepidemi cdisease san d endemicdiseas eoccurrenc ear ereduced ,ther ema yb eles s reasonfo rtransfer so fanimal sbetwee nherds .However ,fo r exampleth epractic eo fsettlin gbridepric ewit hcattle , involvingtransfe ro fth eanimal si tconcerns ,i sno tlikel yt o disappear.Multipl eownershi pan dcommuna lgrazin gresourc eus e will,fo rperfectl y soundreasons ,undoubtedl ycontinu et o prevaili nth eprovince .Th eimportanc eo fcarryin gknowledg e aboutthes efactor si stherefor etha ti tenable sth edesig no f developmentmeasure sfitte dt oth eloca lcircumstance s (Little, 1984).

Inth eWester nProvince ,researc h intosocio-economi c aspectso fcattl ekeepin gwil lhav et ocontinue .Ownership , landtenur ean dgrazin grights ,transfer san dmutua lrelation s betweenher downers ,an drelation sbetwee nher downer san d ownerso fcattl ei nth eher dshould ,wher epossible ,b erelate d toproductivit y andrisk so fproductivit y loss.I ti slikely , thatfiel d studieso fthi skin dwil lpredominantl yb e descriptive,sinc eth elogisti cpossibilitie s foranalytica l studiesma yb esmall .Modellin go nth ebasi so fth einformatio n brought forwardthroug hth efiel dstudie scoul dprov et ob e usefula swell .Th eai mo fthi sresearc hshoul dprimaril ybe , toasses sth epossibilitie so fproductivit y improvementswithi n thelimit so fth esocio-economi ccontext .Th einformatio n resulting fromi tshoul dcom eavailabl ei na shap ei nwhic hi t canb euse d forth eformulatio no flocall yapplicabl eextensio n messages.

201 Asa nexample ,th eformatio no fgrazin gmanagemen to rlan d tenurecommittee sca nb ementioned .Th eexistin gsocia l structurespertainin gt ograzin gright sallocatio nma ypossibl y bechanelle di nthi smanner ,an da foru mma yb eforme di nwhic h alsolan dus eright so fpartie sconcerned ,othe rtha ncattl e keepers,ar earranged .Thi smay ,fo rinstance ,improv eth e situationconcernin g indiscriminateburnin go fgrazin gland . Thetraditiona lauthorities ,a tpresen tke yfigure si nth e allocationo fland ,shoul db einvolve di nprocesse so fthi s kind.

5.6. Theusefulnes so flongitudina lher dmonitoring .

Inth ecours eo fth eher dmonitorin g studyth echoic et o makeus eo fa longitudina lobservationa l studyprove dt ob ea goodone .Variatio nbetwee nyear san dlon ginterval sbetwee n thebirt ho fcalve snecessitat ea longe robservatio nperiod .I t couldeve nb eargue dtha tth eperio do nth ebasi so fwhic hth e resultso fChapte r2 ar ereporte d isstil lrelativel yshort . Increasingth enumbe ro fyear swoul d increaseth ereliabilit y andwoul dparticularl y allowconclusion sfo rlon gter mclimati c variation.Th echaracte ro fa surve yo fthi skin di na developmentprojec tdemands ,however ,a practica lapproac ht o theexecutio no fth estudy .

Itshoul db eremembere dtha ta fiel dsurve yi nth e frameworko fa developmen tprojec tcanno tdevelo pint oa lon g termscientifi cexercise .Th eduratio no fthi spar to fth e monitoring studyallowe d (possiblypartl y indicative) conclusionst ob edraw nalready .Th esam ei stru efo rth e secondpar to fth eprogramme ,whic hi sreporte d inChapte r4.1 . and4.2 .

Physicalher dmonitorin gdoe ssee mt oproduc eusefu l resultst ob euse ddirectl y forth eprojec t inwhic hi ti s carriedout .Genera lproductivit ydat aar eobtaine d ina relativelyobjectiv emanner ,an di na relativel y shortperiod .

5.7. Conclusionsi nrelatio nt oproductivit yan dlivestoc k developmentan dperspectives .

Aswa spointe dou talread yi nChapte r1 ,a nintegrate d approacht olivestoc kdevelopment ,no tonl ytakin g intoaccoun t thepositio no flivestoc ki nth efarmin gsystem ,bu tals o socio-economic aspectso fth elivestoc kindustry ,i s preferable.Keepin gthi si nmind ,an doverviewin gth eresult s obtained inth esurvey sreporte d inthi sthesi sa swel la s

202 thosepresente db yothe rauthor so nth ecattl eo fth eWester n Province,som econclusion sca nb ereached ,tha tma yserv ea s elementso rcondition sfo rlivestoc kdevelopmen teffort stha t are,o rar et obe ,persue di nth eWester nProvince .

- Theveterinar ycomponen t isimportan ti nlivestoc k developmenteffort si ngeneral ,no tonl ybecaus ei t contributest oimprove dhealth ,t oreductio no flosses , andt osustainability ,bu tals obecaus ei tca nb ea ver y goodstartin gpoin tfo rfurthe rintegrate dveterinar yan d zootechnical livestockdevelopmen tefforts .A sfa ra s specificveterinar ymeasure sar econcerned ,organise d veterinary interventionsshoul dai ma treducin gan d controllingth eprevalenc eo fth eimportan tcommunicabl e diseases (HaemorrhagicSepticaemia ,Foo tan dMout h Disease,Trypanosomiasi s etc.).Thi sca nb eexpecte dt o reducelosse smor esignificantl ytha nfo rexampl eth e antiparasitictreatment sstudie dhere .

Whichdisease sth eattentio nshoul db edirecte dto ,i s subjectt ocarefu lconsideration .No tjus tth epresenc eo f thediseas eo rth ediseas eagent ,bu tmor es oth ephysica l damagecause db yi tt obot hindividua lanimal san dth e livestockpopulation ,an dknowledg eo fth eexten to fth e riskst owhic hanimal sar eexposed ,ar eelement si nthi s assessment.Tick-born edisease sfo rinstance ,fo rwhic h obligatory anti-tickdippin go rsprayin g ispractice di n manypart so fAfrica ,prove dt ob eo flittl eimportanc ei n mosto fth etraditiona lherd si nZambia .I nth eabsenc eo f EastCoas tFeve ra soli dpremunit ygenerall yexist s againstmos to fth etick-born ediseases .I fcalve sar e infecteda ta youn gage ,the ymostl ydevelo pa nimmunit y withoutshowin gclinica lsigns .Regula rre-infectio n producesth epremunity .Rigorou stic kcontro ldisrupt sth e premunityan dma ycaus elosse si fi tca nno tb econtinued . Tickcontro lshoul db erestricte dt otreatment so fanimal s thatphysicall ysuffe rfro mth etic kburden .Calve sbor n early inth edr yseaso nma yno tattai na ninfectio nbefor e thetic kpopulatio nrise si nth ewe tseason .The yar e oftenno tyoun genoug ht obecom einfecte dwithou thavin g clinicaldiseas ean ddevelopin gpremunity .I nthes e animalsrarel yclinica lproblem sma yb eseen ,usuall ya sa resulto fheartwate r (causedb yCowdri aruminantium> .

Additionalveterinar yactivitie sprovid erelativel yeas y entrancesi nloca llivestoc kareas .Throug h improvemento f theveterinar y serviceprovisio nt oindividua llivestoc k

203 ownersa tfiel dlevel ,th edeman do ffarmer sfo r possibilitiest ohav eindividua lanimal streate dfo r clinicaldiseas eca nb emet .Eve na tfiel dlevel ,however , theattentio nshoul dno tonl yb edirecte dtoward s veterinaryactivities .Als oi nth eprovisio no fservice s toindividua llivestoc kowner sa nintegrated , multidisciplinaryapproac hshoul db epersued .

Socio-economic featureso fth ecattl ekeepin gsyste m shouldb eregarde dpredominantl ya sconditions ,givin gth e direction forth edevelopmen tefforts .Th epossibilitie s toinfluenc ethe mar ever ysmal lan dindirect .Furthermor e iti shighl yquestionabl ewhethe ri tshoul db eendeavoure d tochang eo rdisrup tstabl esocia lan dcultura lrelation s forth esak eo fimprove dproductivity .I ti sver ylikel y thatthi sproduce sth eopposit eeffec to fwha ti saime d for.

Thedesig no fcost-recover ymeasure sfo rveterinar y servicesi son eo fth eaim so ffiel dstudies .Th eshap e thesemeasure stak ewil lhav et ob emodelle dcarefully , takingsocio-economi c features,an despeciall yth e decisionmakin gprocess ,int oconsideration .Financia l inputsi nth eherds ,specificall y ifaime d forexampl ea t treatmento findividua lanimal swit hdrug so rvaccines , mayb einfluence db yth emultipl eownershi pexistin gi n theherd si nth eWester nProvince .D eRooi jan dWoo d (1990)mentione dtha tchargin g farmersfo rservice sa tth e crushpenwher etreatment stak eplace ,ma yresul ti n partialcoverag eo fth eherd swit hsuc htreatment si fh e cannotb esur eo freimbursmen to fth echarge sb yth eothe r ownerso fcattl ei nth eherd .Th eher dmanage rwil lofte n wantt oconfe rwit hth eothe rowner si nth eher dbefor e takinga decision .I twil li nthos ecase sinevitabl ytak e moretim ebefor ea decisio ni sreache d (Beerling,1986) . Anotheraspec tis ,tha ti ffarmer sperceiv ea specifi c servicea sbein go flittl evalue ,th eus eo ftha t particularservic ema ydecline ,whic hcoul dhav enegativ e implicationso nhealt h (DeRooi jan dWood , 1990).Apar t fromcharge sfo rspecifi cservices ,cost-recover ymeasure s cantak eth eshap eo frevenu ecollectio nthroug ha provincialta xo ncattl eowners ,o ra lev yo ncattl e exported fromth eprovince .

Therei sampl eroo mfo roptimisatio no fth econdition sfo r trade.A bette rus eo fth elocall ybase dabbatoi ri s likelyt oprovid epossibilitie s forth edevelopmen to f

204 activitiesrelate dt ovaluatio no fcattl eproducts .Thi s wouldconstitut ea contributio nt oemploymen tdevelopment .

Althoughth evulnerabilit yo fth egrazin gground si sno t consideredt ob ever yhig h (VanGils , 1989),an dth euppe r limitso fth egrazin gcapacit yo fth eprovinc eha sno t beenreache db yfar ,a growin gcattl epopulatio na sa resulto flivestoc kdevelopmen teffort srequire sa continuousattentio nfo rth egrazin gcondition san dth e ecology (Jeanesan dBaars ,1990) .Thi srequire sa rangelandmonitorin gsyste m (Jeanesan dBaars ,1990) ,a s wella sattentio nt oth epossibilitie so fopenin ga sye t unusedgrazin gareas .

Giventh emultipl eownershi pi nherds ,extensio naime da t productivity improvementshoul dai mpredominantl ya t measurestha tinfluenc eth eproductivit yo fth eher da sa whole.The ywoul dhav et orelat et oher dmanagemen t aspectsan defficien tus eo fgrazin gresources .

Thevariabilit y inperformanc ebetwee nanimal si s considerable.Thi swoul d imply,tha tther ei sscop efo r improvemento findividua lperformanc ea swell .I ti slikel y that,i fimprovement sinvolv efinancia linvestment si nth eher d asa whole ,the ywil lno tb epersue db yfarmers ,sinc ethei r impact ishardl yi nbalanc ewit hth einvestments .I twoul d howeverprobabl yb einterestin gt oconside rth epossibilitie s ofgivin gextr aattentio nt oan dinvestin g injus ta fe w individualanimal si na herd .Suc hextr aattentio ncoul dfo r examplecomprise :

harvestingan dstorag eo froughag e (maizestalcks , possiblyhay )t ob efe ddurin gth edr yseaso n (thisma yb e workablei fi ti sdon efo ra fe wanimal sonly) , strategic feedsupplementatio n (maizebra nan dothe rcro p residues),t osuppor tth eanimal sdurin gth edr yseaso n andt oimprov econditio naroun dmatin gtime , controlled siring,includin gth echoic eo fbull sa swel l asdeterminin gth eoptima lmomen to fservice , extracal fcare ,e.g .colostru mprovision ,roofe dcal f pens,cal fpe nhygiene .

Itwoul db eefficien tt ochoos eanimal sfo rthi s individualproductivit yperformanc eprogramm etha tar ealread y aboveaverage .I norde rt ob eabl et od othis ,i tmus tb e possiblet oidentif ythes eanimal si na herd .Th erecor d keepingan ddat aprocessin g systemuse d inth eher dmonitorin g

205 studyi ssuitabl efo rthis .I ti shardl ythinkabl etha tthi s systemcoul db euse d inan yher dtha ti ssuppose dt oengag ei n improvemento fth eproductivit yo fsom eindividua lanimals . Goodmanua lrecor dkeepin gma yb emuc hsimpler ,provide dtha t iti sdon ereliabl yan dconsistently .

Invie wo fth efac ttha tunemploymen trate sar ehig hi n therura larea ,an dtha thardl yalternativ eeducatio n facilitiesar eavailabl efo rschool-drop-outs ,i tcoul deve nb e consideredt oestablis ha secondar y schoolfo rpractica lanima l husbandry.Thi swoul dope npossibilitie s foryoun gpeopl et o engagei na typ eo flightl ycommercialise dcattl ekeeping ,i n theherd sof ,fo rexample ,thei rfathers ,wit hsom eanimal s thatalread yar ethei rproperty .Anothe rpossibilit ycoul db e thatpupil sar egive nanimal sowne db yth eschool ,i na forma l herdingarrangement ,t ostar to nthei rown ,o ri na nalread y existingherd .A nadde dadvantag e is,tha ti nthi smanne r peopletha td ono tposses scattl eca nb estarte d incattl e keeping.I twoul dprobabl y increaseth epossibilitie s forwome n toengag ei ncattl ekeepin ga swell .

Theconcep to festablishin ga leve lo fcommercialise d cattlekeepin gwithi na traditiona lcattl ekeepin gtraditio ni s likelyt ob econfronte dwit hsevera lproblems .Firstl yth e questionshoul db eanswere dwhethe ri twoul db eaccepte db yth e cattlekeepers .Secondly ,researc hshoul db eaime da tth e logisticpossibilitie so fsuc ha programme .Thi spertain st o determiningwhic hsupplemen t feedsar ebes tt ouse ,an dar e bestavailable ,an dwhic hfeedin gstrateg ywoul db emos t advantageous.I tals orelate st oth emarke tfo rth eproduct , especiallymilk .Furthermore ,a thoroug hidentificatio no f properan dworkabl ecattl emanagemen trequirements ,i na sfa r asthe ydiffe rfro mgenera lextension ,woul db enecessary . Whilebein gprobabl yworthwhil econsidering ,establishin gsuc h a systemwoul dstil lrequir ea lo to fthough tan dresearch ,an d a loto fattentio nt oinfrastructur erequirements .

Traditional livestocksystem si nAfric ai ngenera l operate,a si nth eWester nProvinc eo fZambia ,withi nth e limitso fthei renvironment ,bot hphysica lan dsocial .I n generalterms ,thei rmanagemen t iswel ladapte dt othes elimit s (DeLeeu wan dKonandreas ,1982 ,Cossins ,1985) . Itdoe showeve r notmean ,tha tther ewoul db elittl eo rn oroo mfo rimprovemen t ofmanagemen tan dproduction .Careful lstud yo fthes elimit s shouldprovid emean so frationalisatio no fmanagemen tan d optimisationo fth eus eo fth eavailabl eresources .Her downer s oftenconside rproductivit y constraints,especiall y ifthe yar e

206 causedb yth ephysica lenvironment ,t ob einevitable .I f livestockdevelopmen tproject sai ma tproductivit yimprovement , oneo fth eissue st oadres swoul dtherefor eb et oconvinc eher d ownersa swel la sowner so findividua lanimals ,tha tsevera lo f thesefactor sma yb einfluence db ythem .

Thefac ttha ta larg evariatio ni nth eproductiv e performanceo fanimal si spresent ,an dtha ta ninfluenc eo fth e herdmanagemen to nproductivit y islikel yt ob epresent , suggests,tha tperspective sfo rth eimprovemen to fproductivit y arepresent .I ti sver ywel lpossible ,tha trelativel ysimpl e adjustmentsi nth eday-to-da ymanagemen to fth eherd swoul d alreadyproduc efavourabl eproductivit yeffects .Thes e adjustmentscould ,fo rexample ,includ ea rationa lchoic eo f pastures,attentio nt opastur ean dwate rquality ,distance st o becovered ,bu tals opractice san dtimin go freleasin ganimal s fromth ekraal ,th eamoun to ftim eth eanimal sar eallowe dt o feedan dkraa lshiftin g frequencies.Furthe rresearc hshoul d aima tidentifyin gdecisiv efactor si ndail ymanagemen t practices,i norde rt oincorporat eth eresult si nextensio n messages.I ti sessentia ltha tthes eextensio nmessage sbecom e moreproble moriented ,i nstea do fth ecurren tpractice ,i n which standardextensio nmessage s "fromth ebook "ar ecommon . Extensionworker sshoul dtherefor eno tonl yb eequipe dwit h theirtechnica lknowledge ,bu tals owit hth etool st oasses s localsituations ,t oidentif yproblemati c issuesan dt oproduc e locallyapplicabl esolutions .

Epidemiologicalmodellin go fproductivit y aspectso fth e traditional livestockmanagemen tsystem si nth eWester n Province,an dpossibl y insub-Sahara nAfric ai ngeneral ,ma y provea usefu ltoo li nth eassessmen to fenvironmenta lan d managerialrisk st oproductivity .I tcould ,fo rexample ,assis t indeterminin gth eimpac to fdiseases ,takin gint oaccoun tth e frequencyo ftransfe ro fanimals ,a swel la sth ecompositio n anddirectio no ftransfers .Suc ha too lcoul dals oassis ti n assessingth eeffect so finterventions ,suc ha svaccinations , treatmentan dcontro lprogrammes .I tma yals ob eabl et o providebac kgroun d informationo nth einfluenc eo fsocio economicaspect so fcattl ekeeping .I fepidemiologica l modelling isconsidered ,furthe rfiel dresearc hwil lhav et o aima tprovidin gth ebasi cinformatio nnecessar y forthis .

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210 Summary.

Insub-Sahara nAfrica ,traditionall ymanage d livestocki s importantbecaus eo fth eprovisio no fdraugh tpowe ran dmanure , theprovisio no fsecurit yan dinvestmen tpossibilities ,fo rth e provisiono fmea tan dmilk ,an dfo rsocia lpurpose s(eg . brideprice,gifts) . Inth eWester nProvinc eo fZambia ,cattl e areth eonl ylivestoc ko fsignificance .Th esoil so fth e provincevirtuall yentirel yconsis to fKalahar isands ,tha tar e notver ysuitabl efo rcro pproduction ,bu twit ha goo d suitability forextensiv ecattl ekeeping .Cattl ei nth e provincebelon gt oth eBarots ebreed .Thi si sa Sang abreed , witha moderat et oreasonabl epotentia lfo rmea tan dmil k production,whe ncompare dwit hothe rloca lbreeds ,an di f maintainedunde rimprove drang econditions .

A livestockdevelopmen tprojec ti nth eWester nProvinc e (Prov.Vet .Office r (1987),Livestoc kDevelopmen tProjec t WesternProvince ,Projec tDocument )operate swithi nth e Departmento fVeterinar yan dTsets eContro lServices .I ti s aimeda tprovidin ga sustainabl einfrastructur e fordiseas e control,a tassistin gi nth eformulatio no fa cattl e developmentpolicy ,an da tdevelopin ga nintegrate danima l husbandryan danima lhealt hextensio npackag efo rth e traditional farmer.I norde rt oestablis h itsgoals ,th e projectha sengage d ina programm eo fresearc hactivities .I n thisresearch ,anima lhusbandr yan danima lhealth ,bu tals o grasslandexpertise ,sociolog yan deconom ywer einvolved .Par t ofth eresearc hprogramm ewa sth eher dmonitorin gprogramme .

Theai mo fthi sthesi sis ,t oevaluat eth eus eo f longitudinalphysica lmonitorin go fherd so fcattl eunde r traditionalmanagemen t forth edescriptio no fproductiv e performancean didentificatio no ffactor stha tinfluenc e productivity.Thi sevaluatio nshoul dprovid einsigh ti nth e suitabilityo fher dmonitorin g forth eprovisio no fbasi c information forextensio nan dsolution sfo rconstraint st o productivity .

Theher dmonitorin gprogramm ei saime da tcollectin g quantitative informationo nth eproductivit yo fcattl ei nth e province.Knowledg eo fthes easpect swa sneede d forth e identificationo fconstraint st oproductivity ,fo rth e assessmento fth enee d forspecifi cveterinar ymeasures ,an di n ordert ogiv eindication so nth estructur ean ddevelopmen to f theprovincia lherd .

213 Atota lo f5 2herd swa sinvolve d inth efirs tphas eo fth e research (Chapter2.1.) * Theseherd swer ebase d infou ro fth e sixdistrict so fth eprovince .Herd swer ebase d ineac ho ffou r GrazingManagemen tSystem s (GMS). TheGrazin gManagemen t Systemsdiffere d interm so fgrazin gare aan d its'use , vegetation,mai nwate rresources ,an dlargel y inth epractic e oftranshumanc e (periodicallymovin gherd st oothe rgrazin g grounds)o rsedentaris m (herdingth eanimal sfro mon epermanen t basis).Al lanimal si nth eherd swer eindividuall yidentifie d througheartags ,an dth erecord swer etake na tth eleve lo fth e individualanimal .

Deathsan dslaughter swer eevaluate dtogether ,becaus e slaughtersshoul dgenerall yb econsidere demergenc y slaughters (Chapter 2.2.).Statistical ysignifican teffect so nth e combineddeat han dslaughte rfigure swer efoun do fsex ,ag ean d theherd .Sale sfigure swer eals osignificantl yinfluence db y GrazingManagemen tSyste man dhusbandr y system.Significan t seasonalinfluence so ndeat han dslaughte rfigures ,a swel la s onsale sfigures ,coul dals ob eidentified .Th eoveral lsale s figureswer esmalle rtha nth edeat han dslaughte rfigures . Deathsan demergenc y slaughtersmus tb esee na sabsolut e losses,eve nthoug hth emea to fthes eanimal si softe nstil l eateno rsold .Th erevenu ethi sgenerate sis ,however ,fa rles s thantha tgenerate db ysale so fanimals .

Thepercentag eo fcow stha tcalv ediffer sconsiderabl y betweenGrazin gManagemen tSystem s (Chapter 2.3.).Thi sfigur e is, however,influence db yth eproportio no fanimal stha tmov e intoan dou to fth eherds ,an dtha tspen d lesstha na yea ri n theherd .Thi sproportio nals odiffer sconsiderabl ybetwee n herds.

Significant influenceso nth emea nlength so fcalvin g intervalswer efoun do fth eGrazin gManagemen tSyste m (GMS)an d theparity .Cow so fwhic hth ecal fdied ,o rwa sno tweaned ,an d whichwer eno tmilke dals oshowe da longe rcalvin ginterval . Thecalvin ginterval sar elonges ti nGM S1 .Als oseasonalit yi n calving seemst ob emos tclea ri nthi sGMS .I nGM S2 ,th e intervalbetwee nth ebirt ho fa cal fan dth emomen tth efarme r startsmilkin gth eco wi ssignificantl yshorte rtha ni nmos to f theothe rGMS .A tth esam etim eth elengt ho fth eperio dtha t thecow sar emilke d islongest ,an dth einterva lbetwee n weaningo fth ecal fan dth ebirt ho fth enex tcal fi sshortest .

Theseaso ni nwhic hth ecal fwa sbor nals osignificantl y influencedth einterva lbetwee ncalvin gan dth emomen tth eco w

214 wasmilke d forth efirs ttime ,th elengt ho fth emilkin gperio d andth eag eo fth ecal fa tweaning .Th egirt hwa sgenerall y influencedb yGMS ,se xan dseason .I nGM S1 th enegativ e influenceo fenvironmenta lcircumstance so nproductivit yseeme d biggest,i nGM S2 smallest .

Thenumbe ro fowner sinvolve d inth eherd stha twer e included inth eprogramm evarie dconsiderabl y (Chapter 2.4.). Mostowner si na her dbelonge dt oth efamil yo rrelative so f theher downer .Th emajorit yo fcattl eowner sar emen ,an dth e averagenumbe ro fanimal sowne db yme ni stwic ea sbi ga stha t ownedb ywomen .Th enumbe ro fowner si na her dwa spositivel y relatedt oth esiz eo fth eherd .On ethir do fal lremoval s from,an dentrie sint oth eherd sconsiste do ftransfer sfro m oneher dt oanother ,mostl ybecaus eo fherdin garrangements . Alsobridepric epayment sar ea nimportan treaso nfo rtransfer s ofanimals .Th eownershi pan dth etransfer sbetwee nherd sar e likelyt oinfluenc edecision-makin gprocesse si nth eherds . Transfersma ypos erisk so finfection ,bu tma yals ob eaime da t reducingrisk sbecaus eo fdiseas eoutbreaks .

Diseases,i nparticula rthos ecause db yhelmint h parasites,ar econsidere d importantconstraint st oproductivit y inth etropic s (Chapter 3). Livestockowner sals oofte n considerparasiti cdisease sa sa majo rreaso nfo rdepresse d bodyconditio nan dconsequentl y fordepresse dproductivity .I n theWester nProvince ,th eliverfluk eFasciol aqicrantic aha sa highprevalence .A si nman yothe rarea so fAfrica ,floodplai n grazing isa nimportan t factori nth eepidemiolog yo fthi s parasite.A seasona linfluenc ei sals opresen ti nman yarea si n Africa.

Adistinc tseasona linfluenc ei sidentifie d inman yarea s inAfric ao nth eepidemiolog yo fintestina lhelminths .Thi si s importantlyrelate dt oth esurviva lchance so fth elarva l stagesoutsid eth evertebrat ehost .I nth edr yseaso nn olarva l activityo npastur ei sfound .Th elac ko fmoisture ,rathe rtha n thetemperature ,seem st ob eth emajo rdeterminant .

Theexten tt owhic hanimal ssuffe rfro minfection swit h intestinalhelminth san dliverfluke si spartl ydetermine db y previousexposure .Afte rpreviou sexposur eth eanimal sdevelo p resistanceagains tre-infection ,a sa resul to fwhic hth e numbero fhelminth stha tmature ,a swel la sth eadvers eeffect s of infectionar ereduced .Thi si sth eresul to fdevelopmen to f immunity,an dalso ,specificall y inliverfluke ,o ffibrosi san d calcificationo flive rtissue .

215 Theinfluenc eo finfection swit hliverfluke san d intestinalhelminth so nproductivit y isofte nevaluate dthroug h measuringth eeffect so ngrowt ho rweight .I nth eWester n Province,however ,animal sbein gsol dfo rslaughte rar e normally selected fromolde ranimals .Therefor ereproductiv e performancean dparameter ssuc ha smortalit yan dslaughte r figureswoul db emor eimportant .

Inth esecon dphas eo fth eresearch ,th einterventio n programme,tw oroutin etreatment sagains tliverfuke s (either Rafoxanideo rTriclabendazole )wer eincluded ,a swel la stw o routinetreatment sagains tintestina lhelminth s (either Avermectineo rThiabendazole) ,an don ecombine droutin e treatmentagains tbot hgroup so fparasite s (bothRafoxanid ean d Thiabendazole).A tota lo f2 0herd swa sinvolve d inth e interventiontrials .

Hardlyan ysignifican tdifference scoul db eidentifie dfo r theinfluenc eo ftreatmen tagains tliverfluke s (Chapter 4.1.). Inth eRafoxanid egroup ,par to fth etreate danimal sha da slightly largergirth .Als oa significantl y shorterinterva l betweenweanin gan dth enex tdeliver ywa sfoun dfo rtreate d animalsi nthi sgroup .I nbot hgirt han dth einterval srelate d toreproductio nan dlactatio ndifference swer efoun d forothe r factorstha nth etreatment ,suc ha sseason ,her dan dsex . Deathsan dslaughter sfo remergenc ywer eno tsignificantl y influencedb ytreatmen tagains tliverflukes .Significan t differencescoul db eidentifie d forth eher d inthi sanalysis .

Theintervention ,involvin gtreatment sagains t intestinal parasitesan da combine dtreatmen tagains tintestina lhelminth s andliverflukes ,als oshowe dsignifican t influenceso fseason , sexan dher d insevera lo fth eparameters ,bu thardl yan yo f treatment (Chapter 4.2.). Inth eAvermectin etrial ,th egirt h oftreate danimal swa slarger .A significan teffec to f treatmento ndeath san dslaughters ,a ta confidenc eleve lo f .90,wa sfoun di nth eThiabendazol egroup .I ti slikely ,tha ta clinicalproble mo fgastro-intestina lparasitis mwa spresen ti n theseherds .Analysi so ffaeca lsample sshowed ,tha tth e largestpercentag epositiv esample swa sfoun d inth esecon d halfo fth ewe tseason .

Theinterventio ntrial sseeme dt oproduc elittl eo rn o favourableeffect so ftreatmen tagains teithe r liverflukeso r intestinalhelminth s (Chapter 4.3.). Iti spossible ,tha tpar t ofthes eresult sca nb eexplaine db yth ecircumstance sunde r whichth etrial swer ecarrie dou tan dth etria ldesign .Mor e

216 importantly,i ti slikely ,tha tbot hliverfluke san dintestina l helminths,thoug hpresent ,ar ei ngenera lno ta seriou s problem.Th elo wnumber so fegg sfoun di nfaeca lsample s suggestthis .Individua lcase sd ooccur ,an dlarg epercentage s ofanimal sar elikel yt ob einfected ,bu tth ephysica ldamag e doneb ythes einfection si seithe rsmall ,maske db yothe r factors,o ri sa fa rles sinfluencia l factortha nfactor ssuc h asnutrition ,managemen to rgrazin genvironment .

Evensmal ldifference sbetwee ntreate dan duntreate d animalscoul deconomicall y justifyth eus eo froutin e treatments,eve ni fth eschedule sar erelativel y intensive,i f thecos to fapplicatio n isno tincluded .However ,managemen to f theher dan dmanagemen to fenvironmenta l factorsar emor e importantelement si nimprovemen to fproductivity .

Severalaspect so fth eher dmanagemen tca nb ementione da s influenceso nth eproductivit yo fth eherd s (Chapter 5). These includecollectio no fmanure ,causin gpressur eo ngrazin gtime , thefrequenc yo fkraa lshifting ,especiall y forcalves ,day-to daychoic eo fpasture st ograze ,th equalit yo fherdsmen ,an d uncontrolledburnin go fgrassland .Competitio nbetwee ncal fan d manfo rth emil ko fth ecow si sno tlikel yt ob ea nimportan t negativeinfluenc ei ncal fhealth .

Furtherresearc hint oday-to-da ymanagemen t factorsi n relationt oth eproductiv eperformanc eo fanimal san dherd si s necessaryt oprovid eth ebasi sfo rextension .Ownershi p division,th enumbe ro fowner san dthei rrelatio nt oth eher d ownerand ,i fpossible ,environmenta l factorsshoul db e included inthi sresearch .

Economican dsocio-economi c factorsar edeterminan t factorsi nlivestoc kdevelopment .Custom sconcernin ganima l husbandry,trad econdition san dcommuna llan dus emanagemen t areo fimportance .

217 Samenvatting.

InAfrika ,te nzuide nva nd eSahara ,i straditionee l gehoudenve eva nbelan gvanweg etrekkrach te nmest , bestaanszekerheid end emogelijkhei dt einvesteren ,vanweg e vleese nmelkvoorzienin ge no mee naanta lsocial e (bijvoorbeeld bruidsprijs,giften )redene n (Hoofdstuk 1). Ind eWester n Provincei nZambi ai srundve ehe tenig eve eva nbetekenis .D e bodemi nd eprovinci ebestaa tbijn agehee lui tKalahari-zand , voorhe tmerendee lnie ter ggeschik tvoo rakkerbouw ,maa rwe l geschiktvoo rextensiev eveehouderij .He trundve ei nd e provinciebehoor tto the tBarotse-ras .Di ti see nSanga-ras , redelijkgeschik tvoo rmelk -e nvleesproducti ei nvergelijkin g metander elokal erassen ,wannee rz eonde rgoed eomstandighede n wordengehouden .

Eenveeteeltontwikkelingsprojec t ind eWester nProvinc e (ProvincialVeterinar yOffice r (1987),Livestoc kDevelopmen t ProjectWester nProvince ,Projec tDocument )werk tonde rhe t Departmento fVeterinar yan dTsets eContro lService s (de VeterinaireDienst) .He theef tal sdoe lhe tto tstan dbrenge n vanee ngoed einfrastructuu rvoo rdierziektenbestrijding ,he t leverenva nee nbijdrag eaa nee n veeteeltontwikkelingsstrategie,e nhe tto tstan dbrenge nva n eengeïntegreer dvoorlichtingspakke tme t zowelzoötechnisch e alsveterinair eelemente nvoo rd etraditionel eveehouder .O m dezedoele nt ebereiken ,i see naanta londerzoeksactiviteite n gestart.I ndi tprogramm aword taandach tgeschonke naa n dierhouderije ndiergezondheid ,maa roo kaa nexpertis eo phe t gebiedva ngrasland ,sociologi ee neconomie .Ee nonderdee lva n hetresearchprogramm awa she ther dmonitorin gprogramma .

Hether dmonitorin gprogramm a isero pgericht , kwantitatieve informatiet everzamele nove rd eproductivitei t vanhe tve ei nd eprovincie .Kenni shierove rwa snodig ,o m knelpunten ind eproductivitei taa nhe tlich tt ebrengen ,o m eeninschattin gt emake nva nd ebehoeft eaa nspecifiek e veterinairemaatregelen ,e no minformati et everschaffe n omtrentd estructuu re nd eontwikkelin gva nd erundveepopulati e ind eprovincie .

Hetdoe lva ndi tproefschrif t is,he tgebrui kva nfysie k monitorenva ntraditionee lgehoude nkudde srundve eove rlanger e perioden,teneind eproductivitei tt ebeschrijve ne nfactore nt e identificerendi eproductivitei tbeïnvloeden ,t eevalueren . Dezeevaluati edien t inzichtt everschaffe n ind egeschikthei d vanmonitorin gva nkudde svoo rhe tverzamele nva n

219 basisinformatie,te nbehoev eva nd evoorlichtin ge nvoo rhe t vindenva noplossinge nvoo rknelpunte nvoo rd eproductiviteit .

Intotaa lware n5 2kudde sbi jd eeerst efas eva nhe t onderzoekbetrokke n (Hoofdstuk 2.1.)* Dezekudde sware n gevestigd invie rva nd eze sdistricte ni nd eprovincie .Z e warengevestig d inel kva nvie rGrazin gManagemen tSystem s (GMS). Dezeverschille nva nelkaa rvoo rwa tbetref the t graasgebiede nhe tgebrui kervan ,d evegetatie ,d e belangrijkstewatervoorziening ,e ni nhe ta lda nnie talgemee n zijnva ntranshumanc e (heto pregelmatig ebasi sverplaatse nva n hetve enaa rander egraasgronden )o fsedentarism e (hetweide n vanhe tve evanui téé npermanent ebasis) . Allediere ni nd e kuddeswerde nindividuee lgeïdentificeer ddoo rmidde lva n oormerken,e nd einformati ewer do pbasi sva nindividuel e dierenvastgelegd .

Omdatslachtinge nvrijwe laltij dnoodslachtinge nzijn , zijnd esterft ee nd eslachtinge ngezamenlij kgeëvalueer d (Hoofdstuk 2.2.).Statistisc h significanteeffecte nva n geslacht,leeftij de nkudd eo psterft ee nnoodslachtin gko n wordenaangetoond .Verkoopcijfer swerde noo ksignifican t beïnvloeddoo rhe tGrazin gManagemen tSyste me nhe t houderijsysteem (transhumanceo fsedentarisme) .Zowe lo p sterftee nslachtinge nal so pverkoo pwerde n seizoensinvloeden gevonden.He tpercentag everkocht ediere nwa skleine rda nhe t aantalda tstier fo fwer dgeslacht .Sterft ee nslachtinge n moetenal sabsoluu tverlie sworde ngezien ,hoewe lhe tvlee sva n gestorvendiere nvaa kno gwe lword tgegete no fverkocht .D e inkomstendi edaarui tworde nbetrokke nzij nechte rvee llage r danwannee r levendediere nworde nverkocht .

Hetpercentag ekoeie nda tkalf tverschil taanzienlij k tussend eGrazin gManagemen tSystem s (Hoofdstuk 2.3.).Di t percentageword techte rster kbeïnvloe ddoo rhe taanta ldiere n dataa nkudde sword ttoegevoeg do ferui tword tverwijderd ,e n datminde rda nee njaa ri nd ekudd eaanwezi g is.Oo kda t laatsteaanta ldiere nverschil tster ktusse nkuddes .

Erbestonde nsignificant everschille n ind e tussenkalftijdenvoo rd edivers eGrazin gManagemen tSystem se n voorverschillend epariteiten .Al skoeie nnie tworde ngemolken , ofal she tkal fsterft ,blijk td etussenkalftij dlange rt e zijn.D etussenkalftij di she tlangst ei nGM S1 .I ndi tGM Swa s ookhe tmees tduidelij kee nafkalfseizoe nt eherkennen .I nGM S 2wa she tinterva ltusse nd egeboort eva nhe tkal fe nhe t momentda td eko evoo rhe teers tgemolke nword tsignifican t

220 korterda ni nd emeest eandere .Tegelijkertij dduur td e lactatieperiodehe tlangst ,e ni she tinterva ltusse nspene ne n hetvolgend ekal fhe tkortst .

Hetgeboorteseizoe nva nhe tkal fbeïnvloed the tinterva l tussend egeboort ee nhe tmomen tda td eko evoo rhe teers t gemolkenwordt ,d elengt eva nd elactatieperiod ee nd e speenleeftijdva nhe tkalf .D eborstomvang ,al safgeleidd e parameterva nhe tgewicht ,word tme tnam ebeïnvloe ddoo rGMS , geslachte nseizoen .I nGM S1 lijke nd eomgevingsfactore nhe t meestd eproductivitei tnegatie ft ebeïnvloeden ,i nGM S2 he t minst.

Hetaanta leigenare nva ndiere ni nd ekudde si nhe t programmawa szee rvariabe l (Chapter2.4.) .D emeest emede eigenareni nee nkudd ebehore nto td efamili eva nd ekudde eigenaar.He tbelangrijkst edee lva nd ediere ni si nhe tbezi t vanmannen ,e nmanne nbezitte ngemiddel dtwe emaa lzovee l dierenal svrouwen .He taanta leigenare nda tdiere nbezi ti n eenkudd ei ssignifican tgerelateer daa nd egroott eva nd e kudde.Ongevee ree nderd eva nd edieren ,di ed ekudd ei no fui t gaan,doe tda tvanweg everplaatsinge ntusse nkuddes ,me tnam e vanwegeverzorgingsovereenkomsten .Betalin gva nd ebruidsprij s isoo kee nbelangrijk erede nvoo rverplaatsinge nva ndieren . Hetverschijnse lda te rmeerder eeigenare n inee nkudd ezijn , end efrequenti ewaarme ediere nworde novergeplaatst ,kunne nd e besluitvormingove rdiere ni nd ekudd ebeïnvloeden . Dierverplaatsingen kunnenoo kzeker erisico' sva n infectieoverdrachtme tzic hmeebrengen ,maa rkunne noo kjuis t gericht zijno phe tspreide nva ngezondheidsrisico's .

Ziekten,me tnam everoorzaak tdoo rgastro-intestinal e parasieten,worde ngezie nal see nbelangrijk ebelemmerin gvoo r productiviteit ind etrope n (Hoofdstuk 3). Veehouders beschouwenparasitair eziekte noo kveela lal see nbelangrijk e oorzaakvoo rslecht elichaamsconditi ee ndaardoo rvoo rlag e productiviteit.I nd eWester nProvinc ekom td eleverbo t Fasciolaaiaantic avee lvoor .Zoal si nvee lander egebiede ni n Afrika,speel the tbegraze nva nd eoverstromingsvlakt eva n rivierenee ngrot ero li nd eepidemiologi eva ndez eparasiet . Voorvel egebiede ni nAfrik ai se roo kee nseizoensinvloe d gevonden.

Eenduidelijk eseizoensinvloe d isoo kgevonde ni nvee l delenva nAfrik ao pd eepidemiologi eva nmaag-darmwormen .Di t heeftt emake nme td eoverlevingskanse nva nd elarval estadi a buitend egastheer .I nhe tdrog eseizoe nword tgee nactivitei t

221 vanlarve ngevonde no pd eweidegronden .He tgebre kaa nvocht , ennie tzozee rd etemperatuur ,lijk thie rd ebelangrijkst e remmendefactor .

Demat ewaari ndiere nt elijde nhebbe nva ninfectie sme t maag-darmwormene nleverbotte n isdeel safhankelij kva neerder e infecties.N avoo rhe teers tee ninfecti eo pt elopen , ontwikkelen zeee nzeker eweerstan dtege nher-infectie , waardoorword the taanta lworme nda tto tvoll ewasdo mkom t kleiner is,terwij loo kd enegatiev egevolge nva nd einfecti e minderernsti gzijn .Di ti she tresultaa tva n immuniteitsontwikkeling,e ni nhe tgeva lva n leverbotinfecties ookva ncalcificati ee nfibroserin gva nd elever .

Deinvloe dva ninfectie sme tleverbotte ne nmaag darmwormeno pd eproductivitei tword tveela lgemete ndoo rhe t effecto pd egroe io fhe tgewicht .I nd eWester nProvinc e wordendieren ,di evoo rd eslach tverkoch tworden ,echte r gewoonlijkgekoze nui td eouder edieren .Parameter sdi e betrekkinghebbe no pd evoortplantin ge nsterft ee n verkoopcijfers zijndaaro mbelangrijker .

Terbepalin gva nd eindicatie ,diere nroutinemati gt e behandelentege nleverbotte no fmaag-darmwormen ,i sd ekosten - batenverhoudingee nbelangrij konderdee lva nd ediscussie . Daaromware ni nd etweed efas eva nhe ther dmonitorin g programmad eeffecte nva nbehandelinge no pproductivitei t onderwerpva nonderzoek .Ee ndaaropvolgen ddoe lwas ,d e economischeimplicatie sva ndez ebehandelinge nt emeten ,o md e levensvatbaarheid vand egebruikt ebehandelingsschema' st e bepalen,o fo md emaximal ekoste nva nee nlevensvatbaa rschem a vastt estellen .

Ind etweed efas eva nhe tonderzoek ,he t interventieprogramma,werde ntwe eroutinematig ebehandelin g tegenleverbotte n (ófRafoxanide ,ó fTriclabendazole) ,zowe l alstwe ebehandelinge ntege nmaag-darmworme n (ófThiabendazole , ófAvermectine) ,e nee nbehandelin gtege nbeid egroepe n parasietenuitgevoer d (zowelRafoxanid eal sThiabendazole) .I n totaalware n2 0kudde sbi jhe tinterventieonderzoe kbetrokken .

Erwerde nvrijwe lgee nsignificant everschille naangetoon d voord einvloe dva nbehandelin gtege nleverbotte n (Hoofdstuk 4.1.).Allee ni nd eRafoxanidegroe pwer dee nee niet sgroter e borstomvanggevonde nvoo ree ndee lva nd ebehandeld edieren .I n dezegroe pwer doo kee nkorte r intervaltusse nhe tspene nva n hetkal fe nd egeboort eva nhe tvolgend egevonde nbi jd e

222 behandeldedieren .Zowe lbi jd eborstomvang ,al sbi jd e intervallendi eme tvoortplantin ge nlactati et emake nhebben , werdensignificant everschille ngevonde nvoo rander efactore n danbehandeling ,zoal she tseizoen ,d ekudd ee nhe tgeslacht . Sterftee nnoodslachtingscijfer swerde nnie tsignifican tdoo r behandelingtege nleverbotte nbeïnvloed .Significant e verschillenkonde ni ndez egevalle nworde ngevonde nvoo rd e kudde.

Ind eproeven ,waarbi jbehandelinge ntege nmaag-darmworme n werdentoegepast ,werde neveneen ssignificant einvloede n gevondenva nhe tseizoen ,he tgeslach te nd ekudd evoo r verschillendeparameters ,maa rbijn agee nva nd ebehandelinge n (Hoofdstuk 4.2.). Ind eAvermectinegroe pwa sd eborstomvan gva n behandeldediere ngroter .Bi jd eThiabendazolegroe pwer dbi j eenbetrouwbaarhei dva n .90ee neffec tva nd ebehandelin g gezien.Waarschijnlij kwa si ndez ekudde sklinisch emaag - darmwormziekteaanwezig .Bi janalys eva nmestmonster so p parasieteneierenblijkt ,da the tgrootst eaanta lpositiev e mestmonsterswer dgevonde ni nd etweed ehelf tva nhe t regenseizoen.

Hetinterventieprogramm a lietweini go fgee ngunstig e effectenva nbehandelin gtege nhetzi jleverbotten ,hetzi jmaag darmwormenzie n (Hoofdstuk 4.3.).He ti smogelijk ,da tee ndee l vandez eresultate nverklaar dka nworde ndoo rd eomstandighede n waaronderhe tonderzoe kwer duitgevoer de nhe tontwer pva nd e trial.Ee nbelangrijker erede ni swaarschijnlijk ,da tzowe l leverbottenal smaag-darmwormen ,hoewe laanwezig ,i nhe t algemeengee ngroo tproblee m zijn.D elag eaantalle neiere ndi e ind emestmonster swerde ngevonde nwijze ndaa roo kop . Individuelegevalle nkome nvoor ,e ngrot epercentage sdiere n zullenwaarschijnlij kgeïnfecteer d zijn,maa rd efysiek eschad e diedoo rdez einfectie sword tveroorzaak t isechte rslecht s klein,o fword tdoo rander efactore ngemaskeerd ,o f isee n factorva nvee lminde rinvloe dda nfactore nzoal svoeding , managemente ngraasgebied .

Zelfsbi jklein everschille ntusse nbehandeld ee n onbehandeldedieren ,e nzelf sbi jrelatie f intensieve behandelingsschema's,ka nui teconomisc hoogpun ta l rechtvaardigingvoo rroutinebehandelinge nworde nafgeleid ,al s hierbijd etoedieningskoste nnie tworde nberekend .Managemen t vand ekudd ee nva nomgevingsfactore n zijnechte rbelangrijker e voorwaardenvoo rproductiviteitsverbetering .

Verschillendeaspecte nva nd edierhouderi jkunne ngenoem d

223 wordenal smogelijk einvloede no pd eproductivitei tva nd e kuddes (Hoofdstuk 5). Hiertoebehore nhe tverzamele nva nmest , waardoord egraastij donde rdru kkomt ,d efrequenti ewaarme ed e kraalword tverzet ,voora lvoo rkalveren ,d edagelijks ekeuz e vand et ebegraze nweide ,d ekwalitei tva nherder se nhe t ongecontroleerd brandenva ngraasgronden .He tonttrekke nva n melkvoo rhuman econsumpti ete nkost eva nhe tkal fheef t waarschijnlijkgee nbelangrijk einvloe do pd egezondhei dva nd e kalveren.

Verderonderzoe knaa rhe tdagelijks emanagemen t inrelati e totd eproductivitei tva nrundere ne nkudde si snoodzakelij ko m debasi st elevere nvoo rvoorlichting .I ndi tonderzoe kzoude n ookaspecte nzoal sd everdelin gva nhe teigendom ,he taanta l diereigenarene nhu nrelati eto td eeigenaa rva nd ekudd eaa n deord emoete nkomen ,evenals ,indie nmogelijk , omgevingsinvloeden.

Economischee nsocio-economisch efactore nzij nbepalend e factorenvoo rveeteeltontwikkeling .Gewoonte ndi egerelateer d zijnaa nd eveehouderij ,handelsomstandighede ne n gemeenschappelijkgraslandgebrui kzij nva nbelang .

224 Acknowledgements/dankwoord.

APh .D .thesi si shardl yeve rth ewor ko fonl yon eperson . Manypeopl ehave ,i nman yvariou sways ,contribute dt oth e completiono fthi sthesis .Firs to fall ,I woul d liket o expressm ygratitud etoward sth eher downers ,wh ohav etaken - part inth eher dmonitorin gprogramme .The ycontinue dt ob e cooperativean dpatient ,i nspit eo fth efac ttha ther dvisit s musthav ebee npryin gsometimes ,bu twer ealway sinterferin g withdail yroutine .

Ials ogreatl yacknowledg eth econtributio no fth estaf fo fth e Departmento fVeterinar yan dTsets eContro lService si nth e WesternProvince ,bot hveterinar yprofessiona lan dfiel dstaff , andth estaf fo fth eAnima lDiseas eContro lProjec tan d LivestockDevelopmen tProject ,wh ower einvolve d inth eher d monitoringprogramme :th eVeterinar yAssistant san dSenio r VeterinaryAssistants ,wh oha dt opa ytwo-weekl yvisit st oth e herds,an dth eDistric tVet san dprojec tstaf fmembers ,wh o visitedth eherd sever ythre emonths ,an dwer egreatl y responsible forcorrec trecording .Withou tthei rcontinue d efforts,non eo fthi swoul dhav ecom eabout .I woul d liket o mentionspecificall ym ypredecessor ,Han sCorten ,wh oplaye da n importantpar t instartin gu pth eher dmonitorin gprogramme , andm ysuccessor ,Luu kSchoonman ,wh ocarrie do nwit hth e programmefo rquit esom etim eafte rI left .

Therespectiv eDirector so fth eDepartmen to fVeterinar yan d TsetseContro lService so fth eRepubli co fZambi aar e acknowledged forthei rcontinue d interest inth eprogramme ,an d thepermissio nt opublis hth eresult so fth estudy .

TheAnima lDiseas eContro lProjec t (ADCP)Wester nProvinc ean d theLivestoc kDevelopmen tProjec t (LDP)Wester nProvinc e providedmos to fth efacilitie snecessar yt ocarr you tth e researchdescribe d inthi sthesis .Ro bd eRooij ,teamleade ro f bothprojects ,an dlater ,throug hRD PLivestoc kServices , responsible forimplementatio no fth eLDP ,i sgreatl y acknowledged forhi senthousiasti can dinspirin ginteres ti n thestudies .H ei sals oacknowledge d forhi spoin to fview , thaton eshoul dno thav et omes sabou to ninadequat eequipment . Thispoin to fvie wprovide du swit hth ebes ttool sfo rth e fieldwor kan dth edat aprocessing .Neve rmin dtha tkey-boar d goingnut sbecaus eo fgljsbsvvasljgstati celectricity .

Ikwi ld emedewerker sva nd eSecti eTropisch eVeehouderij ,di e mijal shu ncolleg abeschouwde n ind etij dda ti kmij n

225 studieverlofbi jhe ndeed ,bedanke nvoo rd eprettig ewerksfee r enbelangstellin g indi ecrucial eeerst emaanden .Voora lBenni e Brouwerwi li kdaarbi jnoemen ,di emi jassistenti everleend e bijd estatistiek .Oo kKlaa sFrankena ,va nd eSecti e Gezondheidsleer,heef ti nee nlate rstadiu mvee laa nmij n statistischekenni sbijgeschaafd .

Graagwi li kmij npromotoren ,Professo rDr .D .Zwar te n ProfessorDr .J.P.T.M .Noordhuize nbedanke nvoo rhu n stimulerendebegeleiding .Voora lhe tstrakk eschem ava n maandelijksebijeenkomste nhebbe ner ,zeke rd elaatst e anderhalf jaar,zee rto ebijgedrage nda ti kaa nhe twer kbleef . Ikwi ljulli edaarnaas too kbedanke nvoo rhe tvertrouwe nda t jullie,blijken sjulli einzet ,steed si nmi jhebbe ngehad .

DeDirecti eva nd eVeterinair eDiens twi li kbedanke nvoo rhe t feit,da tik ,naas tmij ngewon ewerk ,o pgezett etijde nd etij d mochtneme no maa ndi tproefschrif tt ewerken .

Tenslott ewi li kgraa gmij nvrou we ndochter sbedanken ,voo r hungeduld ,maa rvoora loo kvoo rhe tfeit ,da tzi jvoo rmi jee n belangrijke inspirerendee nmotiverend ebasi swaren .Riann eko n mijbovendie nvaa kletterlij k ("moestji jvanavon dnie tnaa r boven?")aa nd egan ghouden .Al si kjulli enie tha d

226 CurriculumVitae .

EngelbertusGerardu sMari ava nKlin kwer dgebore no p1 9 november 1956t eAlphe naa nde nRijn .N ahe tdoorlope nva nhe t Gymnasium ß aanhe tChristelij kLyceu maldaar ,wer d in197 5me t destudi ediergeneeskund et eUtrech tbegonnen .I n198 3 studeerdehi jaf .N aenig etij dbetrokke nt ezij ngewees tbi j degeorganiseerd edierziektebestrijding ,e nn aanderhal fjaa r werkzaamt ezij ngewees tal sonderzoeksassisten tbi jd e VakgroepVoedingsmiddele nva nDierlijk eOorspron gva nd e FakulteitDiergeneeskund et eUtrecht ,vertro khi ji n198 5naa r deWester nProvinc ei nZambia .Hie rwer dhe tonderzoe kverrich t opbasi swaarva ndi tproefschrif t issamengesteld .Hi jvervuld e defunkti eva nDistric tVeterinar yOffice ri nhe tdistric t Seshekei nd eWester nProvinc egedurend eee nperiod eva n tweeëneenhalf jaar.Daarn ai shi jgedurend eeenzelfd eperiod e werkzaamgewees tal sVeterinar yResearc hOffice ri nMongu ,d e hoofdplaatsva nd eWester nProvince .Sind smaar t199 1i shi j alsbeleidsmedewerke rwerkzaa mbi jd eVeterinair eDiens tva n hetMinisteri eva nLandbouw ,Natuurbehee re nVisseri jt eDe n Haag.

EngelbertusGerardu sMari ava nKlin kwa sbor no n19t hNovembe r 1956i nAlphe naa nde nRijn ,Th eNetherlands .Afte rcompletin g Gymnasium ß atth eloca lLyceum ,h estudie dveterinar ymedicin e from197 5til l198 3a tth eUniversit yo fUtrecht .Afte r graduation,h ewa sinvolve d invaccinatio ncampaigns ,an d worked foron ean da hal fyear sa sa researc hassistan t inth e Departmento fth eScienc eo fFoo do fAnima lOrigi no fth e Facultyo fVeterinar yMedicin eo fth eUniversit yo fUtrecht .I n 1985h ewen tt oth eWester nProvinc eo fZambia ,wher eth e researchwa scarrie dou ttha ti sth ebasi so fthi sPh .D . thesis.H eworke da sDistric tVeterinar yOffice rfo rSeshek e District inth eWester nProvinc efo rtw oan da hal fyears ,an d fora simila rperio da sVeterinar yResearc hOffice ri nMongu , thecapita lo fth eWester nProvince .Sinc eMarc h199 1h ei s employeda sa polic yoffice ra tth eVeterinar yServic eo fth e Ministryo fAgriculture ,Natur eManagemen tan dFisherie so fTh e Netherlands inTh eHague .

227 Photograph cover: Jan van der Spree, Gouda Span of oxen with sledge, wood carving, Senanga, Western Province, Zambia.