Turk.J.Vet.Anim.Sci. 30(2006)533-538 ©TÜB‹TAK ResearchArticle EffectsofMicrowaveCookingontheInfectivityof Toxocaracanis (Werner,1782)LarvaeintheLiverofParatenicHostMice HandanÇET‹NKAYA1,AyflenGARGILI2,*,KemalALTAfi2 1DepartmentofParasitology,FacultyofVeterinaryMedicine,‹stanbulUniversity,‹stanbul-TURKEY 2DepartmentofMicrobiologyandClinicalMicrobiology,CerrahpaflaMedicalFaculty,‹stanbul-TURKEY Received:26.07.2005 Abstract: Thisstudywasconductedtodeterminetheeffectofmicrowavecookingontheinfectivestagesof Toxocaracanis larvae foundinthetissuesofparatenichosts.Forthispurpose,3seriesofexperimentswerecarriedoutusingahouseholdmicrowave oven(2450MHz,model:ArçelikMD551)atmedium,medium-highandhighlevels.Atotalof54micewereusedinthe3 experiments.Toxocaracanis eggswerecollectedfromthefaecesofnaturallyinfecteddogsandincubatedatroomtemperaturefor 4weeksfordevelopmentofinfectivelarvaeineggs.Inthefirstexperiment,6micewereeachinfectedwith3000larvatedeggs of T.canis orally.Infectedmiceweresacrificedontheseconddayofinfectionandeachliverwastakenout,mincedwithascalpel, mixedtoprovidehomogeneityandseparatedinto3equalpartsafterweighing.Allmiceliversweighedapproximately1g.One-third ofeachliverwasgiventoonemouserawandanotherthirdofeachliverwasdigestedina1%pepsin-HClsolutionat37°Cfor 3 daystosearchfor T.canis larvae.Theremainingthirdsoftheliverswerefedtoonemouseaftermicrowavecookingatmedium levelfor5min.Sincethemiceliversweresosmalltheywerecoveredwithstretchcookingfilmandputinsidechickenlivers (each approximately52g,1.7cmthick)toobtainanormalsizedcookingsamplebeforemicrowavetreatment.Sampleswereputinside themicrowaveoveninthecentreandcookedseparately.Thentheliversweretakenoutoftheovenandthetemperatureinsidethe liverwasmeasuredimmediately.Themicefedonrawliverandmicrowave-treatedliverweresacrificedafter2days.Thelungs, livers,carcasses,hearts,spleensandkidneysofeachmousewereputintopepsin-HCldigestionsolutionandexaminedfor T.canis larvaeunderastereomicroscope.Thesecondandthirdseriesofexperimentswerecarriedoutjustlikethefirstexperimentexc ept forthecookinglevelsofthemicrowave,whichweremedium-highandhigh.Variousnumbersoflarvaewerefoundintheorgans ofmicefeduncookedinfectedliver,butnolarvaewerefoundinthemicefedmicrowave-processedinfectedlivers. KeyWords: Microwavecooking,Toxocaracanis,infectivity MikrodalgaF›r›ndaPiflirme‹fllemininParatenikKonakOlanFarelerin Karaci¤erindekiToxocaracanis (Werner,1782)Larvalar›naEtkisi Özet: Buçal›flmaparatenikkonakdokular›ndabulunaninfektifToxocaracanis larvalar›namikrodalgapiflirmeifllemininetkisiniortaya koymakamac›ylayap›ld›.Buamaçiçinüçserideney,medium,medium-high,highfonksiyonlar›olanevtipimikrodalgaf›r›n(245 0 MHz,ArçelikMD551)kullan›larakyürütüldü.Üçdeneydetoplam54adetfarekullan›ld›. Toxocaracanis yumurtalar›do¤alenfekte köpe¤ind›flk›s›ndantopland›veiçindeinfektiflarvalar›ngeliflmesiiçinodas›cakl›¤›nda4haftasüreyleinkübasyonab›rak›ld ›.Birinci deneyde6fareninherbiri3000larval› T.canis yumurtas›ileoralolarakenfekteedildi.Enfekteedilenfareler,enfeksiyonun2. günündeaç›larakkaraci¤erlerial›nd›,skalpelilek›y›ld›,homojeniteyisa¤lamakiçinkar›flt›r›ld›vetart›ld›ktansonraüçefl itparçaya ayr›ld›.Herbirfareninkaraci¤eriyaklafl›k1gramd›.Herbirkaraci¤erin1/3’üçi¤olarakbirfareyeyedirildive1/3’ü T.canis larvas› aranmaküzere%1’likpepsin-HClsolusyonunda37°C‘de3günsindirimeb›rak›ld›.Karaci¤eringerikalan1/3’ümikrodalgada mediumseviyesinde5dakikapiflirildiktensonrabirfareyeyedirildi.Farekaraci¤erlerininçokküçükboyuttaolmalar›nedeniyl e normalpiflirmeboyutunusa¤lamakiçinmikrodalgadapiflirmedenöncefarekaraci¤erleristreçpiflirmefilmleriilesar›ld›vetav uk karaci¤erinin(herbiriyaklafl›k52g,1,7cmkal›nl›¤›nda)içinekondu.Örneklertektekmikrodalgaf›r›n›npiflirmetablas›n›nortas›na yerlefltirilerek5dakikasüreylepiflirildi.Mikrodalgaf›r›ndanç›kar›lanörnekleriniçs›cakl›¤›hementermometreileölçüldü. Çi¤ve mikrodalgailepiflirilmiflkaraci¤erleriyiyenfareler2günsonrasakrifiyeedildi.Herfareninakci¤er,karaci¤er,karkas,kal p,dalak veböbrekleripepsin-HClsolusyonundasindirimeb›rak›ld›vestereomikroskopta T.canis larvalar›arand›.‹kinciveüçüncüdeneyler demikrodalgan›nmedium-highvehigholanpiflirmeseviyelerid›fl›ndatamamenbirincideneyindizayn›ndayürütüldü.Karaci¤erler in içerisindekis›cakl›kmikrodalgauygulamas›ndansonraüçdeneydede70°C’ninüzerindeydi.Çi¤infektifkaraci¤erilebeslenen farelerinorganlar›ndaçeflitlisay›lardalarvabulunurkenmikrodalgadapiflirilmiflinfektifkaraci¤erlebeslenenfarelerdelarva ya rastlanmad›. AnahtarSözcükler: Mikrodalga,Toxocaracanis,infektivite *E-mail:[email protected] 533 EffectsofMicrowaveCookingontheInfectivityof Toxocaracanis (Werner,1782)LarvaeintheLiverofParatenicHostMice Introduction infectioninhumansbyeatinginfectedorgansofparatenic Inrecentyears,theuseofmicrowaveovensfor hostsaftermicrowavecooking. householdfoodcookingprocesseshasincreased; therefore,itisofgreatimportancetoclarifytheeffects MaterialsandMethods ofmicrowavecookingoninfectiousagentsinfood products. Animals: Atotalof54Balb-Cmice,8weeksold, wereusedinthisstudy.Micewerekeptona12-h Studieshavebeendoneonthebactericidaleffectof light/darkphotoperiodandfedonastandardmicediet microwaveovensoncontaminatedfoods(1,2).A andtapwateradlibitum. microwaveovenhasbeenusedforinactivationof8 virusessuspendedindrinkingwater(3).Anotherstudy Obtainingandpreparationof T.canis eggs: T. examinedtheeffectofamicrowaveovenforthe canis eggswereobtainedfromthefaecesofnaturally decontaminationofdiagnosticsamplesandsterilisationof infecteddogs.Collectedeggswereincubatedin1% contaminatedmaterialsinthelaboratory(4). formalin-salineatroomtemperaturefor4weeksuntil larvaldevelopmentoccurred(13). Severalstudieshavebeencarriedouttodeterminethe effectofmicrowaveovensontheinactivationofsome Microwavetreatment: Ahouseholdmicrowaveoven parasitesfoundinfood(5-7).LundenandUggla(6) (2450MHz,model:ArçelikMD551)wasusedtocook appliedmicrowaveheatingtomuttoninfectedwith mouselivercontaining T.canis larvae.Theovenhad5 Toxoplasmagondii cystsandfoundthattheparasite processfunctions:warm,defrost,medium,medium-high remainedinfective,possiblyduetounevenheatingofthe andhigh.Forthisstudy,3functions,i.e.medium, meat.Kotulaetal.(5)havereportedthatcookingpork medium-highandhigh,wereusedforcookingthemouse chopsincluding Trichinellaspiralis larvaerapidlyina livers.Theliverswereplacedinthecentreoftheoven microwaveovento77or82°Cdidnotcompletely onebyoneandwereexposedtomicrowaveheatingfor5 destroytheinfectivityofthemeat.Microwaveirradiation min.tobecookedproperly.Thetemperaturesinsidethe wasreportedtobeextremelyeffectiveinkillingor liversweremeasuredimmediatelywithathermometer preventingthedevelopmentof Eimerianieschulzi, afterthemicrowavetreatment. Strongyloidesratti andTaeniataeniaeformis (4).Anisakis Experimentaldesign: Thefirstexperimentwas simplex larvaeinfishfilletswereshowntobekilledata establishedtodeterminetheeffectofmicrowaveheating minimumof77°C(7). ontheinfectivityof T.canis larvaeinthemouseliverat Toxocaracanis (Werner,1782)isaparasitethatlives mediumlevelheating.Sixmicewereeachinfectedwith intheintestineofcanidae.Larvaeofthisnematodecause 3000larvatedeggsof T.canis orally.Basedonthe aninfectionreferredtoasVisceralLarvaMigrans(VLM) informationthatlarvaltrappingandaccumulationofthe inhumansandotherparatenichosts(8).Humansbecome migratinglarvaeintheliveroccurred42hafterinfection infectednotonlybytheingestionofinfectiveeggs,but (14,15),infectedmiceweresacrificedonthesecondday alsobyconsumingtheraworundercookedliverormeat ofinfection.Eachliverwastakenout,mincedwitha ofchickensorcowsthatcontain T.canis larvae(9,10). scalpelandmixedtoprovidehomogeneityandseparated Bouchet(11)demonstratedthatabriefexposureto into3equalpartsafterweighing.Themouselivers microwaveheatinginterruptedthedevelopmentof T. weighedapproximately1g. canis eggsandshowedthealteredultrastructureofthe One-thirdofeachliverwasgiventoonemouseraw, eggsaftermicroheatinginanotherstudy(12).The andanotherthirdafterexposuretomicrowaveheating effectsofmicrowavecookingontheinfectivityofT.canis for5minatmediumlevel.Sincetheliversofthemice larvaeinthetissueofparatenichostshavenotbeen weresosmall,theywerecoveredwithstretchcooking reported. filmandputinsidecommerciallyavailablechickenlivers Thisstudywascarriedouttoshowwhether measuringapproximately52gand1.7cmthick,to microwavecookinghadanyeffectontheinfectivityofT. exemplifythenormalsizeofamealbeforeheating.The canis larvaeintheliverofmice,theparatenichost.Mice mouseliverswithintheliversofthechickenswereputin wereusedasamodeltoshowthepossibilityofVLM aglassdishseparately,coveredwithstretchfilmagain 534 HÇET‹NKAYA,A.GARGILI,K.ALTAfi andwereplacedinthemicrowaveoveninamarked presenceof T.canis larvaeafterthe3experimentshad centralpositiononebyoneandweretreatedatmedium beencompleted. levelfor5min.Thenthesamplesweretakenoutofthe microwaveoven,andthetemperatureinsidewas measuredwithathermometer.Thentheliversofthe Results miceweretakenoutofthechickenlivers,lefttocoolfor Thelarvaefoundinthethirdsoftheliverofmice 5minandeachsamplefedtoonemouse. inoculatedwithT.canis eggspreviouslywerecountedand Theremainingthirdofeachliverwasincubatedat37 theaveragenumbersofthelarvaeingestedby °Cfordigestioninpepsin-HClsolution(13)and T.canis experimentalmicewerecalculated(inthesecondcolumns larvaewereexaminedunderastereomicroscopeafter3 ofTables1-3).Allmicethathavebeenfedonraw days.Thepresenceandthenumberoflarvaeinthispart infectedliverwerefoundtohavebeeninvadedbyT.canis oftheliverwasimportanttoprovethatthemiceliver larvae.Thenumbersanddistributionofthelarvaeinthe washarbouringthelarvaeandtoestimatethenumberof organsofthemiceareshowninTables1-3.Nolarvae larvaethatthemicehadingestedbyeatingtherawand