ANNUAL REPORT 1969/70
VETERINARY SERVICES
INDEX
1. INTRODUCTION 1
2. NOTIFIABLE DISEASES 2 [1] Foot and Mouth Disease 2 [2] Rabies 3 [3] Anthrax 4 [4] East Coast Fever and Releated Diseases 4 [5] Tuberculosis 4 [6] Brucellosis 5
[7] Trypanosomiasis 7 1. Nagana 7 2. Dourine 9
[8] Lumpy Skin Disease 10 [9] Sheep Scab 10 [10] Mange 11 [11] Swine Fever 12 [12] Swine Erysipelas 12 [13] Epizootic Lymphanigtis 12 [14] Johne’s Disease 12 [15] Infectious Laryngotracheitis 12 [16] Rinderpest 13 [17] Newcastle Disease 13 [18] Bacillary White Diarrhoea and Fowl Typhoid 13 [19] Fowl Cholera 14 [20] Psittacosis 14
[21] Other Notifiable Diseases 14 1. Scrapie 14 2. Equine Infectious Anaemia 14 3. Glanders 14 4. Bovine Pleuropneumonia 14
3. NON-NOTIFIABLE DISEASES 15 [1] Deficiency and Nutritional Diseases 15 [2] Poisoning 17 1. Mineral Poisoning 17 2. Plant Poisoning 18 3. Toxins 19
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[3] Bacterial Diseases 19 1. Mastitis 19 2. Enterotoxaemia 19 3. Blackquarter 20 4. “Lamsiekte” 20 5. Corynebacteriasis 20 6. Pasteurellosis 21 7. Tetanus 21 8. Colibacillosis 21 9. Leptospirosis 22 10. Vibrionic Dysentry of Pigs 22 11. Pseudomonas Infection 22 12. Lamb Dysentry 23 13. Actinobacillosis and Actinomyeosis 23 14. Staphylococcus aureus 23
[4] Protozoal Diseases 23 1. General 23 2. Babesiosis 23 3. Anaplasmosis 24 4. Besnoitiosis 24 5. Coccidiosis 24
[5] Virus Diseases 25 1. Blue Tongue 25 2. Horsesickness 25 3. Heartwater 26 4. Ephemeral Fever 27 5. Rift Valley Fever and Wesselsbron Disease 27 6. “Snotsiekte” 27 7. Respiratory Diseases of Poultry 27 8. Fowl Pox 27 9. “Jaagsiekte” 27 10. Virus Pneumonia of Pigs 28 11. Enquine Rhino-pneumonitis 28
[6] Infertility and Vernereal Diseases 28 1. General 28 2. Vibriosis 28 3. Trichomoniasis 28 4. Infectious Infertility 29
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[7] Diseases of Calves 29 1. White Scours 29 2. Paratyphoid 29 3. Coccidiosis 29 4. Calf Diphtheria 29 5. Sweating Sickness 29
[8] Internal Parasites 30 [9] External Parasites 31
4. OTHER VETERINARY RESEARCH 33 [1] Basic Research 33 [2] Miscellaneous Research and Projects 37 [3] Research on Diseases of Game 37 [4] Blood Group Studies 38
5. VACCINE PRODUCTION 38
6. OTHER VETERINARY SERVICES 41 [1] Diagnostic Services 41 [2] Surveys 42 [3] Clinical Services 44 [4] Artificial Insemination 44
7. HEALTH SCHEMES 45 [1] Bacillary White Diarrhoea 45 [2] P.P.L.O. Scheme 45 [3] Pig Recording and Health Scheme 46
8. MEAT INSPECTION 46 9. STOCK INSPECTION SERVICES 48 10. ANIMAL HEALTH EXTENSION SERVICE 49
11. IMPORT AND EXPORT CONTROL 49 [1] Import 49 [2] Export 50
12. TRAINING 51
13. STOCK CENSUS 53
14. PUBLICATIONS 54
15. LEGISLATION 62
16. TECHNICAL RELATIONS WITH OTHER COUNTRIES 63
ANNUAL REPORT 1969/70
VETERINARY SERVICES
1. INTRODUCTION
The implementation of a scheme for the re-distribution of the re-distribution of the inspectorate staff of the Division of Veterinary Services, to ensure a more evenly balanced and more efficient stock inspection service in all parts of the Republic, was put into operation during the year under review. This implementation, as well as routine services, was severely hampered by staff deficiencies – a considerable number of vacancies existed in both the professional and inspectorate sectors – and outbreaks of epizootic diseases.
An outbreak of Foot and Mouth Disease in game in the Kruger National Park necessitated the drafting of additional personnel from all over the country for intensified patrolling of the approximately 640 km of game proof fencing on the southern and western borders of the Park, and intensified stock inspection in the adjacent farming areas.
At the same time more than 60 members of the personnel of the Division were seconded to Swaziland to assist that country in combating an outbreak of Foot and Mouth Disease.
The measures against Foot and Mouth Disease were so successful that the disease spread to domestic animals in the Republic at one point only, the Bantu area of the Komati ward in the Barberton district, and was contained on the originally infected localities.
In addition the Division had to contend with an outbreak of mesogenic Newcastle Disease in a Bantu area in the Port Elizabeth district, while sheep scab appeared in 7 Cape and 3 Transvaal districts.
At the Veterinary Institute, Onderstepoort, research on the development of an improved oil adjuvant vaccine against enterotoxaemia has been completed, but due to technical problems the issue of this vaccine has been delayed. This vaccine should become available during the year.
The experimental work on vaccines against vibriosis and leptospirosis has been completed and Treasury authority is awaited before the vaccines are released for sale. Although considerable progress has been made, the research on a vaccine against three-day-stiffsickness is continuing.
As in the past, only a limited quantity of the live vaccine against colibacillosis and colisepticaemia of calves and lambs was prepared and issued. However, the experimental work on a killed vaccine, which will confer a better immunity, is nearly completed and the vaccine should become available during the year.
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Plastic containers were introduced for the bottling of vaccines during the year. This has led to a significant saving in respect of breakages of the glass bottles previously employed and has facilited the handling, packaging and transport of vaccines.
Lungsickness vaccine is now being produced at a rate of 250 000 doses per week. The vaccine is used to control Lungsickness in Ovamboland.
2. NOTIFIABLE DISEASE
[1] FOOT AND MOUTH DISEASE
As early as July 1969 warning was given by the Mocambique authorities of the presence of Foot and Mouth Disease near the eastern border of the Republic. Patrols on the international border and on the borders of the Kruger National Park were immediately strengthened.
During April 1970 the first cases of the disease within the Republic were found, in the central area of the Kruger National Park, in impala. By the end of June infection had spread throughout the Park.
Then on October 14, 1969 Foot and Mouth Disease was discovered in the Mbuzini dipping tank area of the Komati ward of the Barberton district and one week later in the adjacent Tabankulu area. The whole affected area was cordoned off and all stock within the cordon artificially virused. This included 3 305 cattle, 217 sheep and 757 goats. Clinical end point was reached on November 24, 1969.
On November 28, 1969 Foot and Mouth Disease was diagnosed in cattle in the neighbouring Masimini dipping tank area, the outbreak involving 8 173 cattle, 598 sheep and 1 465 goats. The infected area was immediately sealed off by cordon, and the 16 246 cattle, 1 196 sheep and 2 930 goats within the cordon vaccinated twice at an interval of three weeks with SWA 4/69 vaccine. As a precautionary measure 70 404 cattle, 5 377 sheep and 11 941 goats in the adjacent areas were similarly vaccinated. Three weeks after the second vaccination, all stock within the infected cordon were artificially virused.
In both the Mbuzini and Masimini outbrekas, infection was contained within the originally affected area.
Along all the other land borders of the Republic strict precautionary measures against the introduction of Foot and Mouth Disease were maintained. These included regular patrol and repair of the international border fences, short interval inspections of all susceptible stock in the border areas and the destruction of animals straying in or illegally introduced from adjacent territories. The latter involved 9 cattle, 9 sheep and 118 goats with an estimated total value of R960.
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[2] RABIES
During the twelve months July 1, 1969 – June 30, 1970 a total of 640 specimens was submitted to the Central Investigation Centre at Onderstepoort for examination. Of these 169 [26.6%] were found positive, with the following species distribution:
Meercats ……………………………….66 Cattle ……………………………………45 Wild cats ………………………………..18 Dogs …………………………………….11 Jackals …………………………………. 8 Domestic cats …………………………. 6 Sheep ………………………………….. 4 Other animals ………………………….10 Human …………………………………. 1
Compared to the previous year, both the number of specimens submitted and the positive findings show a marked decrease. Especially gratifying is the 75% decrease in canine rabies, and the fact that not a single case occurred in the epizootic canine rabies areas of Natal. On the Central Plateau, where meercats play the leading role as disseminators of the disease, cases in the O.F.S. and Highveld Regions decreased from 92 tot 27 and from 75 to 63 respectively. As it is reported from the O.F.S. Region that more skeletons than live meercats are found in the majority of viverrid habitations, it is possible that the prolonged severe drought has been an important contributory factor in this dramatic improvement in the viverrid rabies position.
The annual compaigns for the immunisation of dogs in the declared rabies areas of the Natal Region, and the immunisation of all dogs within a radius of 15-25 km around all confirmed outbreaks, were continued during the year. A total of 147 752 dogs and 21 cats were vaccinated.
The destruction of viverridae by mobile units in recognised infected areas on the Central Plateau continued during the year. Eradication was undertaken on 114 939 ha [234 farms], and 51 954 colonies and 16 651 single holes gassed.
The one human case of rabies recorded in February 1970 was that of a man who died after allegedly being bitten by a bat. Credence is lent to the story by the fact that the virus isolated at the Central Investigation Centra differs in several respects from the ordinary rabies “street” virus strains.
The Central Laboratory continued to examine suspect rabies material from South West Africa and Swaziland. Further supplies of rabies fluorescent antibody conjugate were made available to Rhodesia, Botswana and Mocambique, while a shipment was supplied to S.W.A for trial work in their investigation centre. At the request of a Bolivian visitor, a quantity of
conjugate was also sent to that country for testing in the diagnosis of bat rabies. 4/…
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[3] ANTHRAX
During the year 15 outbreaks occurred in domestic stock, while in the Kruger National Park the disease was diagnosed as the cause of death of one kudu.
In two Bantu areas, one in each of the districts of Taung and Kuruman, where all cattle are vaccinated annually under supervision, the outbreak was diagnosed only after considerable mortality had occurred in small stock. In the case of the Kuruman outbreak the area was vacant as the result of the absence of the Asst. Stock Inspector on special duties, and the outbreak only reported after 15 Bantu had contracted Anthrax. Fortunately only one human fatality occurred.
A total of 4 535 640 cattle, 245 739 small stock, 18 459 equines and 315 pigs were vaccinated by or under the supervision of officers of the Veterinary Division.
Taking into consideration the lengthy absence of so many officers of the Division from their normal areas on campaign and other special duties, the figures for precautionary inoculations are gratifyingly high.
[4] EAST COAST FEVER AND RELATED DISEASES
Although no cases of East Coast Fever have occurred since the disease was eradicated in 1954, continued vigilance is maintained in the previously affected areas. The highest possible percentage of spleen smears from cattle that die or are slaughtered is collected for laboratory examination.
The total cattle population of these areas is 3 165 853 and 355 287 deaths were recorded during the year. The spleen smears examined – 379 489 – included smears collected but not examined during the latter part of the previous twelve month period.
Examination of smears disclosed 9 cases of Buffalo Disease [Theileria Lawrencei] and 36 cases of Benign Bovine Theileriasis [T.mutans]. No mortality resulted from these two diseased, which were controlled by short term quarantine and intensified tick control measures.
[5] TUBERCULOSIS
Various modifications to the bovine tuberculosis eradication scheme were introduced towards the end of the previous report year. Among these modifications were the utilisation of the services of private practitioners not only in conducting tuberculin tests under the interim scheme, but under the accreditation scheme as well; the tracing back, wherever possible, to the herd of origin of any tuberculosis infection found at tuberculin testing, abattoir
slaughter, milk examination or in any other way; the placing under official control of all infected herds, with compulsory testing and elimination of reactors; and finally, State compensation for all reactors slaughtered. 5/…
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These extensions and refinements to the scheme led to a considerable increase in the number of tests performed and the elimination of reactors during the year under review, so that herds accredited under the scheme now number 944.
The tests carried out during the year are tabulated below:-
RESULTS TEST NUMBER ANIMALS POSITIVE SUSPICIOUS OF HERDS TESTED INH 14 3 639 211 79 IMPORT & 320 4 727 6 4 EXPORT DIAGNOSTIC 407 15 596 75 59 INTERIM 1 017 120 493 2 654 859 ACCREDITATION 971 119 977 658 164 TOTAL 2 729 264 432 3 604 1 165
The total number of animals tested shows an increase of 99 234 over the figure for 1968/69, and represents 2.4% of the total cattle population of the Republic. The incidence of reactors, with tests under the accreditation scheme excluded, is 2.04% positive and 0.69% suspicious.
The amount spent on the scheme during the year was approximately R228 553, of which compensation for animals slaughtered amounted to R160 252, test fees and travelling allowances paid out to private practitioners totalled R61 301, while identifying ear tags for animals tested, and other equipment, accounted for R7 000.
Condemnation of pig carcases at abattoirs for either generalised or localised tuberculoses continued to cause relatively high financial losses.
Three outbreaks of avian tuberculosis were reported during the year, one each in the districts of Bethlehem, Kimberley and Mafikeng. These outbreaks occurred in small backyard flocks, and were eliminated by slaughter of the affected flocks.
[6] BRUCELLOSIS
In the Annual Report for 1968/69 it was indicated that as from December 13, 1968 the vaccination of all heifer calves between the ages of 3 and 10 months was compulsory. Also that all heifers immunised under official supervision receive a special earmark to distinguish such animals when elimination of
infected animals – the final stage in the eradication of bovine brucellosis – is reached. 6/…
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Unfortunately no great progress can be reported for the year under review. This is mainly due in the first place to the fact that the vaccine was not a free issue, thus leading to time consuming delays caused by the non-availability of vaccine when officers arrived at farms on routine visits. Secondly, the campaign functions of the Division severely handicapped a full scale vaccination effort in connection with this disease.
At the Onderstepoort and Regional Investigational Centres the following serological tests for brucellosis were carried out:
RESULTS SPECIES NUMBER POSITIVE SUSPICIOUS TESTED Cattle 70 144 6 925 [9.9%] 1 261 Sheep 3 572 202 [5.7%] 54 Goats 38 21 - Game 514 43 22
The high percentage of positive findings reflected above cannot be taken as a true indication of the incidence of the disease. In many cases specimens originate from herds in which it is desired to pin point infected animals, or to confirm suspicion of infection. Vaccination of adult animals further complicates the picture.
Onderstepoort issued 844 277 dosis of Strain 19 and 352 600 dosis of Rev. 1 vaccine during the year. A total of 108 645 cattle and 15 340 sheep were vaccinated by officers of the Division.
The Veterinary Research Institute reports that: a] A long term project in which the serological response to S19 vaccine is being studied, is still in progress. b] An oil adjuvant vaccine was formulated and has given very good results. Initial experiments in guinea pigs resulted in a protection rate of 83%.
c] Extensive experiments with Rev. 1 vaccine in cattle also gave very good results. Only 1/10th of the normal dose for S19 vaccine gave a protection of 80-90%. There were no adverse reactions and undesirable serological reactions were minimal. However, as S19 vaccine is universally established, it will remain the standard product for cattle.
d] By means of absorption of immune sera and Complement fixation tests, a definite relationship between Br. ovis and Br. abortus was established. This finding is an important contribution to the problem of Brucella taxonomy.
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[7] TRYPANOSOMIASIS
1. NAGANA
Once again during the past year no positive cases of Nagana were diagnosed.
From July to October 1969 tsetse fly spraying operations were carried on beyond the borders of the Republic, in Rhodesia and Mocambique, and also in the Caprivi and adjacent areas. It was possible to confine the mopping up operations in Rhodesia to 225 km2, of which 169 km2 was sprayed by the conventional method for drainage systems, while 56 km2 without any visible drainage system was sprayed on the more intensive parallel line or grid system. For this 7t of 75% D.D.T. wettable powder was used.
In Mocambique, Rhodesian spraying teams under supervision of officials of the Republic, sprayed a total of 650 km2, of which 363 km2 was sprayed by the conventional and 175 km2 on the grid system, using 12.58t of 75% D.D.T. wettable powder, while 7166.251 of Dieldrin 15[T] concentrate was used on 112 km2 of which 56 km2 was sprayed by the conventional and 56 km2 on th grid system. Additionally an adjacent area of approximately 784 km2 was sprayed with 7.9t of D.D.T. wettable powder by the conventional method by two Mocambique spraying teams under supervision of South African officials.
In the spraying areas in Rhodesia and Mocambique a total of 4 896 km of parallel lines, riverines, valleys and contacts were sprayed, using 27.5t D.D.T. wettable powder and 7 166.251 Dieldrin concentrate, compared to 3 702 km sprayed the previous year. The contribution of the Republic to the campaign was 1 Senior Technician to control and co-ordinate the campaign as a whole, 6 officials to supervise spraying units, 8x2.7t lorries with drivers, 3 Land Rovers and 7 166,251 Dieldrex 15[T] concentrate. The financial contributions to the campaign were as follows:
R.S.A RHODESIA MOCAMBIBIQUE TOTAL R20 492 R23 714 R14 888 R59 094
The present favourable position in Rhodesia is that only single flies can be caught with the aid of bait animals, in a localised area adjacent to the Mocambique border. In ten test herds run in the area cleared of tsetse fly in Rhodesia, isolated cases of nagana were diagnosed during the past year only in three herds adjacent to Mocambique. In Rhodesia tsetse flies have been eliminated from an area approximately 3 200 km2 in extent, to the south of the Sabi and Lundi rivers.
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In Mocambique an extensive area has been cleared of tsetse flies and the major portion of the 1969 campaign in Mocambique was aimed at mopping up operations in all the remaining low fly density areas, over a distance of approximately 144 km east of the Mocambique – Rhodesia border and south of the Rio Save. The results are very encouraging, and a further positive contribution was made in an area of approximately 1 600 km2 where further fly residues were eliminated, and the density of the tsetse population in the remaining restricted areas is so low that only occasional flies can be found after intensive surveys with bait animals. Operations in this area have therefore progressed to the difficult final phase where the remaining fly foci must be determined and exadicated. Work has been facilited by the addition of a further approximately 160 km of access roads, bringing the total of access roads in Mocambique to over 480 km.
THE CAPRIVI TSETSE FLY COMPLEX
As in the past, the funds for the 1969 spraying campaign were provided by the Department of Bantu Administration and Development, while the Division of Veterinary Services organised and controlled the campaign. In accordance with the discussions held at Rundu, S.W.A. on 18 March 69 by representatives of the Republic, Angola and S.W.A., three spraying teams were made available by the Republic, while Angola provided a further three teams for the campaign.
The campaign was planned to include all the remaining tsetse fly infested areas in the Eastern and Western Caprivi and to extend to the north in Angola and the south in Botswana. The spraying areas in the Eastern Caprivi are limited to Sangwali and Lianshulu which are re-infected annually from the untreated adjacent areas in Botswana, and can be regarded as additional mopping up operations. For his purpose a total of 88 km along the banks of the Kwando river in the Eastern Caprivi were sprayed.
In mopping up work in the Bwabwata area in the Western Caprivi a total of 100 km of drainage system and pans were sprayed, compared to 261 km in 1968. Al remaining fly foci in the Western Caprivi were sprayed from the Kwando river to Bwabwata 96 km west, while operations were extended 48 km northwards along the Kwando river into Angola, and in Angola 40 km westwards along drainage areas. This is a new area with a high fly density which was sprayed for the first time. As a result of floods it was not possible to extend the campaign to the low lying areas to the south in Botswana.
In the area covered by the three spraying teams in the 1969 campaign, a total of 867 km of drainage systems, pans and breeding places were sprayed in 41 working days, using 851 of Dieldrex concentrate and 162 kg D.D.T. wettable powder. The expences of the campaign amounted to R18 360, the contribution by the Department of Bantu Administration and Development being R9 963 and that of the Department of Agricultural Technical Services R8 397.
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In Angola the Portuguese operated from Bwabwata in a northern and eastern direction to join up with the operations in the Western Caprivi, and also along the Kwando river in the south-eastern parts of Angola. In addition activities were extended approximately 100 km in a northerly direction as far as the Luiana river. In this way the Portuguese launched their first large scale spraying campaign.
The position in the Eastern Caprivi remains satisfactory in view of the problems connected with the adjacent untreated portions in Botswana, which will only receive the necessary attention during the 1970 campaign. Cattle are not yet allowed into the Sangwali – Lianshulu area. The cattle population in the Eastern Caprivi increased from 24 000 in July 1968 to more than 30 000 in July 1969. In the Western Caprivi a marked improvement was also been seen after the 1968 campaign. Indications are that tsetse flies have been eliminated from the Bwabwata area and the contiguous Angolan areas, so that the threat of an extension to the Okavango river in the west has been averted. The fly problem to the north in Angola has been effectively separated from the southern problem in Botswana by the present satisfactory position in the Caprivi Strip west of the Kwando river as far as Bwabwata.
In view of the results obtained in Rhodesia and Mocambique where D.D.T. and Dieldrex were used in a planned project to compare efficacy, Dieldrin will in future be replaced in the Caprivi as well, by the cheaper and equally efficient D.D.T. wettable powder.
In the Kruger National Park 255 blood smears of game were examined during the year, but all proved negative for nagana, as did 5 elephants examined by the biological rat test. During April/May 1970 a routine survey was undertaken in Zululand: no flies were found in the Hluhluwe-Umfolozi complex, but Glossina brevipalpis appears to be on the increase near St. Lucia.
2. DORINE
During the report year 948 serum specimens from various ports of South Africa and 485 from beyond the borders of the Republic were examined for Dourine at Onderstepoort.
The 29 positive South African cases were from the Transvaal districts of Christiana [1], Klerksdorp [1] and Nigel [1], and the districts of Mafikeng [3], Philipstown [1] and Vryburg [16] in the Cape Province, with an additional 6 positive findings in specimens emanating from the Transkei.
Of the positive reactors within the Republic, 2 mares and 3 stallions were moved to Onderstepoort for experimental work, and the rest either destroyed or castrated.
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Details of the specimens submitted from outside the Republic are tabulated below:-
COUNTRY OF ORIGIN TOTAL SPECIMENS NUMBER POSITIVE South West Africa 317 31 Rhodesia 85 - Botswana 31 11 Zambia 27 - Swaziland 24 - Mocambique 1 -
[8] LUMPY SKIN DISEASE
This disease was recorded in all parts of the Republic during the year, with a total of R38 021 cattle on 193 forms affected. Reports also indicate only isolated outbreaks, except in the Ngotshe, Paulpietersburg and Dundee districts of Natal and Piet Retief in Transvaal, where it occurred widespread. No severe losses were experienced as the disease ran a very mild course.
Onderstepoort issued 441 973 dosis of vaccine during the year, which is 121 394 dosis less than the 1968/69 issue. A total of 47 646 cattle were immunised by or under the supervision of officials of the Division.
[9] SHEEP SCAB
Sheep Scab made its appearance in 5 of the 7 Veterinary Regions of the Republic, with outbreaks recorded in 11 districts, and involved the dipping of 144 879 small stock at least twice and in some cases three times, with an interval of 8-10 days. In the majority of cases the origin of the infection could not be established, but in two outbreaks, one in each of the districts of Vryburg and Mafikeng, indications are that the disease was introduced by sheep smuggled in across the border.
In the Mafikeng outbreak 25 sheep on 2 farms were found infected and 16 091 sheep were dipped to eradicate the disease.
In the Delareyville district of group of 17 sheep on one property were dipped after infection had been established.
A total of 358 infected sheep were found in flocks numbering 4 132 on 11 farms in the Pietersburg district, necessitating the dipping of 12 253 sheep and 3 621 goats on the infected, and 21 567 sheep and 20 280 goats on contact farms.
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The discovery of 156 infected sheep in a flock of 312 on a farm in the Soutpansberg district led to the dipping of 991 sheep on the property and 1 791 sheep and 442 goats on adjoining farms.
In the O.F.S. Region 5 sheep were found infected on a farm in the Gordonia district, and 3 140 sheep and 278 goats on the property and 16 215 sheep and 1 048 goats on adjacent farms were dipped.
In the Kenhardt distrct the dipping of 3 250 sheep and 22 goats on an infected farm and 10 329 sheep and 61 goats on contact farms eradicated infection.
On 6 farms in the Vryburg district with a total of 1 600 sheep, 295 were found infected, necessitating the dipping of these 1 600 sheep and 130 on adjoining farms.
An outbreak involving 38 flocks in the Johannesburg area was uncovered. The 1 091 sheep and 1 OC1 goats in these, as well as 673 sheep and 566 goats in 37 contact flocks, were dipped.
In the Winter Rainfall Region 3 outbreaks occurred, one each in the Tulbagh, Vredenburg and Malmesbury districts.
The Tulbagh outbreak involved 3 stray sheep found at the abatoir, and two adjacent farms. On the infected and contact properties respectively, 770 and 1 626 sheep were dipped to eliminate the infection.
Seven farms in the Vredenburg district were found infected, and 25 926 sheep dipped to control the outbreak.
The infection in the Malmesbury district was discovered on June 24, 1970 and details are not yet available.
[10] MANGE
Isolated cases of mango in cattle, goats, horses and pigs were reported, as shown below. All cases readily responded to hand dressing or dipping of infected and, where necessary, contact animals.
NUMBER OF SPECIES OUTBREAKS ANIMALS ANIMALS ON INFECTED FARMS Cattle 36 251 18 253 Goats 4 26 1 461 Equines 2 2 2 Pigs 19 376 1 223
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In the Kruger National Park Sarcoptes scabei was diagnosed in the impala and blue wildebeest, Demodex bovis and Psoroptes sp. In the buffalo, Notoedres cati in the cheetah and Otodectis cynotes in domestic cats. Sarcoptic mage was incriminated as the cause of mortality in impala and blue wildebeest.
It has been established that the buffalo can be an asymptomatic carrier of both sarcoptic and demodectic mange over extended periods. Efforts to transmit sarcoptic mange from the buffalo to cattle and sheep were unseccessful, but transmission to the blue wildebeest succeeded.
[11] SWINE FEVER
The classical Swine Fever does not occur in the Republic and during the year no cases of African Swine Fever were recorded.
Because of the presence of warthogs and bush pigs, the potential carriers of African Swine Fever, a small portion of the northern and Eastern Transvaal has been declared an enzootic swine fever area. The movement of pigs and pork products within and out of this area is strictly controlled. Pigs may only be moved to outside this area from approved piggeries which have to conform to strict specifications and are subject to regular inspections. Such movements are allowed only to specified quarantine abattiors, from which no meat products may be exported.
[12] SWINE ERYSIPALAS
Three outbreaks in Natal and one each in the Eastern Cape and Transvaal, were confirmed during the year. In every case infection responded readily to antibiotic treatment.
[13] EPIZOOTIC LYMPHANGITIS
No cases of this disease occurred during the year.
[14] JOHNE’S DISEASE
Johne’s Disease was confirmed in one bovine on the Johannesburg sewerage farm. The animal was slaughtered. In the Winter Rainfall Region one case occurred on a farm where an imported cow had shown the disease the previous year. Both these cows have died, and the position is being closely watched.
[15] INFECTIOUS LARYNGOTRACHEITIS
No outbreaks of this disease were reported during the year.
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[16] RINDERPEST
This disease does not occur in the Republic of South Africa or the neighbouring territories.
[17] NEWCASTLE DISEASE
During August, 1969 the mesogenic form of Newcastle Disease was diagnosed in specimens sent to Onderstepoort for examination, after investigation into heavy mortality in fowls in the Bantu areas around Port Elizabeth.
The affected area was immediately quarantined and additional staff drafted in to apply the necessary control measures.
Between September 2 and 15 a total of 10 997 fowls and turkeys were destroyed, while the vaccination of all geese and ducks in the affected area, and all poultry in the surrounding areas at risk, was carried out. The vaccination of older birds were completed by November 10, between which date and December 4 newly hatched chickens were immunised at 4 weeks of age. In all, 828 244 birds were vaccinated.
The measures instituted proved so successful that control could be lifted six months after the outbreak.
The Veterinary Research Institute reports that the Onderstepoort vaccine, which is produced in embryenated eggs, has been adapted to growth in a monkey kidney cell line. Good protection has been obtained against virculent Newcastle disease in birds inoculated with virus grown in cell culture. The few disadvantages of the avianized vaccine can now possible be eliminated.
[18] BACILLARY WHITE DIARRHOEA AND FOWL TYPHOID
During the year one outbreak of B.W.D and 8 of Fowl Typhoid – one in the flock of a certificate holder – were recorded.
Summarised data of tests performed in connection with these two diseases is given below:-
Flocks tested 101 Birds tested 794 804 Positive reactors found 61 Suspicious reactors found 71 B.W.D. & F.T. free certificate holders 96 Birds in flocks of certificate holders 4 720 304
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Onderstepoort issued 1 337 800 doses of Fowl Typhoid vaccine during the year.
The Research Institute reports that, with the object of improving both the keeping quality and effectiveness of the existing Fowl Typhoid vaccine, new mutants were induced.
Thus far, eight mutants have been obtained and are being evaluated.
[19] FOWL CHOLERA
No outbreaks of this disease were reported during the year.
[20] PSITTACOSIS
Only three outbreaks of this disease were reported, one in imported parrots in the Jan Smuts Airport quarantine station, one in racing pigeons in the Warmbaths district, and the third in penguins in the aquarium, East London. Control of infection was established by appropriate measures.
[21] OTHER NOTIFIABLE DISEASES
1. SCRAPIE
No cases of Scrapie occurred during the year. Regular periodical inspections of all flocks to which potentially infected sheep were traced are still being carried out, and all movements from these flocks are subject to permit control to enable further tracing to be done should this be necessary.
2. EQUINE INFECTIOUS ANAEMIA
No cases of this disease were reported during the year.
3. GLANDERS
No outbreaks of Glanders have occurred in the Republic of South Africa for many years.
4. BOVINE PLEUROPNEUMONIA
No cases of Lungsickness have occurred in the Republic of South Africa for the past decades.
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3. NON-NOTIFIABLE DISEASES
[1] DEFICIENCY AND NUTRITIONAL DISEASES
The greater part of the Republic experienced a prolonged severe drought during the year. Grazing was deficient, or in some cases virtually non- existent, while supplementary feed, if available, was very often of poor quality, although only obtainable at exorbitant prices. Stock farmers suffered very severe losses as the result of poor growth, lowered production, loss in reproduction and mortality of both cattle and sheep.
The Winter Rainfall Region also reports fairly widespread paresis and paralysis and other obnormalities, including brain aberrations, in young lambs, and serious mortality in new-born calves, presumably as the result of the mothers being in a poor state of nourishment.
Digestive disturbances, very often with fatal outcome, as a result of artificial feeding in the absence of natural grazing, and low fertility resulting from poor nourishment or imbalances, are reported, especially from the Natal, O.F.S and Winter Rainfall Regions. To make matters worse, imbalances were often aggravated by the indiscriminate feeding of mineral and trace element mixtures recommended by the representatives of feed firms.
Chronic avitaminosis apparently also accurred widespread, while aphosphorosis syndromes were more prevalent than usual in all Regions.
From the Natal Region it is reported that White Muscle Disease was found in two areas, and surveys have indicated avitamenosis and aphosphorosis as the major deficiency problems, with copper and magnesium deficiency on artificial pastures a close second.
In the Winter Rainfall Region diseases of metabolism are regarded as of major importance, and surveys to elucidate the position were continued during the year.
The Veterinary Research Institute reports that during 1968/69 a pilot experiment was carried out to ascertain the supplementary value of a batch of commercial monoammonium phosphate. The conclusions drawn were, that M-AP had supplementary feeding value as source of phosphorus and nitrogen, when it replaced dicalcium phosphate and partially replaced Urea in the ration.
In further studies with a second batch of commercial M-AP., metabolism data showed comparatively lower efficiency. This finding made further research a necessity.
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During the current year further feeding tests and metabolism studies followed. The replacement value of M-Ap with respect to urea, for its nitrogen value, and the phosphorus retention value compared to dicalcium phosphate was studied in balanced rations.
Preliminary conclusions drawn were:
1] Compared with dicalcium phosphate, the phosphorus efficiency is much inferior.
2] The nitrogen-efficiency of peanut meal in a balanced ration, is superior to a peanut-urea ration.
3] Peanut-urea ration is superior to peanut-urea-mono-ammonium phosphate ration, with respect to nitrogen utilization.
According to research done at the Veterinary Institute, high levels of dietary phosphate have been known to induce incidence of phosphatic urinary calculi under experimental conditions. However, variation in mineral intake, as for example calcium level in diets high in phosphorus, tended to reduce the incidence of calculi.
In the present study on a long term basis, high levels of phosphate intake are studied with a variation in basal diet. It is suspected that specific types of feed such as cottonseed oilcake meal, and sorghum are contributory factors in calculi formation when an imbalance of minerals in the diet exists. As a preliminary study a normal basal diet with variation in Phosphate intakes was chosen [Dec. 1969]. Two levels of phosphorus intake, with two types of phosphate, have been studied with a normal phosphorus level as control.
Blood mineral determinations and metabolism trials were done for mineral utilization.
The most important aspect of the first study was that:
[a] at the normal level of phosphorus intake calcium and Magnesium balances were positive, although marginal;
[b] at the high level of acidic sodium phosphate the calcium balance was negative, but the magnesium balance marginal;
[c] at the high level of basic sodium phosphate the calcium balance was again negative, but magnesium balance marginal.
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In connection with growing-finishing pigs, workers at Onderstepoort state that copper added at rates of 250 parts per million [p.p.m.] to pig rations in Britain have resulted in weight gains of ± 8% and improved feed utilization of ± 6%. Equally well controlled experiments primarily in the U.S.A have however given indications of detrimental effects with such additions.
This experiment was designed as a 3x2x2 factorial to evaluate the possible effects of protein source and level graded copper levels and their effects on growing – finishing pigs.
The measurement criteria were six physical carcass characteristics and six chemical analyses bases on liver samples from bacon weight pigs [85 Kg.].
It was found that protein of fish meal origin reduced the copper content of livers from the 205.15 p.p.m. [with sunflower oil cake meal] to 97.38 p.p.m and simultaneously improved leanness, feed conversion and dressed carcass percentage. In the presence of fish meal 150 p.p.m. copper addition gave beneficial responses but these were reduced when copper was increased to 300 p.p.m. Furthermore when the protein source was sunflower oil cake meal instead of fishmeal the carcass quality was lowered. Feed conversion efficiency was poorer and related minerals as iron, zinc, manganese and magnesium were altered in their liver concentration.
It is concluded that copper may be fed at higher levels as a growth stimulant with economic advantage provided a high quality protein as fishmeal is prominent in the formulated ration.
[2] POISONING
1. MINERAL POISONING
Numerous cases of poisoning of animals occurred, in several instances accompanied of heavy mortality. Poisoning resulted from the incorrect of careless use of such materials as salt, urea and remedies against internal parasited, and the accidental or malicious administration of acaricided or other insecticides, or in dogs, strychnine.
The worst instances recorded were the fatal poisoning of 45 in a group of 64 stall fed oxen due to accidental administration of an insecticide in feed, the broadcasting of an arsenic containing termite poison in a camp, which resulted in the death of 22 cattle, and the malicious addition of 22.7 1 of Thoidan to the mixture in a spray dip, which led to the death of 175 cattle within one hour after dipping.
The Central Veterinary Investigation Centre, Onderstepoort, reports that during the year 1 694 specimens, including 124 plant specimens, were received from 787 sources for toxicological examination.
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Of this total 1 521 specimens were chemically analysed and 465 specimens from 204 sources found positive for some poisonous substance.
These positives can be classified as follows:-
POSITIVE SOURCE
Arsenic 94 37 Lead 16 6 Salt [NaC1] 1 1 Mercury 7 3 Copper 1 1 Nitrate 8 4 Cyanide [HCN] 4 2 Urea 9 6 Strychnine 189 103 Sulphur 7 1 Parathion and other organic phosphates 6 3 Dieldrin 4 2 Other chlorinated hydrocarbons 90 26 Megasul [nitrophenide] 12 2 Worm remedies 17 7
465 204
The Research Institute, Onderstepoort, records that recently large numbers of game died in camps where grazing had been sprayed for termite control. Experiments showed that both dieldrin and photodieldrin, formed by the former under such conditions, can be fatal if ingested in small amounts over a long period. These poisons give rise to nerve, liver, heart and muscle lesions and like BHC and DDT are stored for long periods in the fat, liver and bone marrow. This is a further indication of the extreme danger of these insecticides to man and animal.
Onderstepoort also reports that a rapid, easily applied test for the diagnosis strychnine poisoning in dogs has been determined and evaluated. It consists of the injection of stomach contents of the dog into the abdominal cavity of young mice and the findings suggest that the test will be of value to the veterinarian in private practice.
2. PLANT POISONING
From the Regional reports received, it would appear that as a result of the country wide severe drought, stock losses due to plant poisoning occurred on an appreciably reduced scale. The only exception to this was the Winter Rainfall Region, where and increase was experienced, especially in cases of tulp, kraalbos and melkbos [Euphorbia mauritanica] poisoning, due to the dearth of edible green vegatation. 19/…
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The plants responsible for most cases of poisoning in the other Regions were Senecio spp, in the Natal and Transvaal Regions; tulp [Homeria and Moraea spp.] in the Natal, O.F.S. and Transvaal Regions; gifblaar [Dichapetulam cymosum] in the Highveld and Transvaal; gousiekte [Pachystigma pygmaeum] in the Transvaal and Highveld; lantana in Natal and Transvaal, slangkop [Urginea spp.] in the Highveld; and vermeerbos [Gaigeria spp.] in the O.F.S. Region.
According to the Veterinary Research Institute it was recently found that seed- pods of Albizia tanganyicensis, growing in parts of the Transvaal, can cause poisoning in animals. The symptoms are similar to those caused by BHC, DDT and dieldrin poisoning. Another related poisonous tree is also found in Transvaal and Natal.
3. TOXINS
Isolated small scale outbreaks of Diplodia zeae poisoning were reported, while sporadic cases of botulism occurred where baled fodder was fed to stock in the drought stricken areas. Losses in sheep on reaped lupin lands were once again experienced in the Winter Rainfall Region – one farmer lost 800 sheep in this way. A fungus has now definitely been established as the cause, and has been isolated in pure form.
[3] BACTERIAL DISEASES
1. MASTITIS
Mastitis in cattle remained the most serious erosion disease of dairy farming, causing considerable financial loss.
At most of the Veterinary Investigation Centres antibiograms were conducted to enable State Veterinarians to advise on the most efficient treatment to be used in every case of mastitis.
Although these measures cannot eliminate or even control mastitis, it is the best interim scheme until the serious manpower shortage in both the professional and technical fields of the Division has been overcome and a planned anti-mastitis campaign can be launched.
2. ENTEROTOXAEMIA
In all parts of the Republic severe losses were experienced in unvaccinated flocks. Few problems were encountered in flocks where the recommended vaccination regime was carried out. With the new improved oil adjuvant vaccine referred to in the Introduction, the position should improve even further.
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During the year Onderstepoort issued 36 355 800 doses of vaccine, 6 800 050 less than during 1968/69.
3. BLACK QUARTER [CLOSTRIDIUM CHAUVOEI]
Sporadic outbreaks of this disease were encountered throughout the Republic. Fortunately it can be stated that the increased use of vaccine referred to in the previous report, was maintained.
During the year 4 842 232 doses of vaccine were issued, only 65 664 less than during the previous year.
The Veterinary Research Institute reports that fractionation of the standard vaccine with polyethylene glycol showed that the antigen which induces immunity is present primarily in the culture supernatant.
Experiments with vaccine which was produced in celophane sacks proved that depending on the growth stage, both the bacterial cells and the culture fluid in the bag are able to afford protection.
In connection with Clostridium septicum Onderstepoort states that a culture medium suitable for vaccine production has been developed.
Satisfactory results have been obtained with the vaccine in guinea pigs. It has also been shown that both the bacterial cells and the culture supernatant are able to induce immunity.
The vaccine contained no measureable toxin andit appears that immunity can be obtained without this product.
4. “LAMSIEKTE”
Although no heavy mortalities in any herds or flocks were reported in any locality, sporadic cases of botulism occurred in all ports of the country.
A total of 4 553 270 doses of vaccine was issued by Onderstepoort during the year, a slight increase on the 1968/69 issues.
5. CORYNEBACTERIASIS
From Regional reports received it would appear that especially in certain areas Corynebacteriasis in both sheep and cattle is on the increase. In the absence of reliable statistics it is impossible to gauge whether the increase is actual or only due to a greater awareness of the condition.
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The Research Institute, Onderstepoort reports that field trials with different vaccines proved that the best immune response was obtained with vaccine containing aluminium phosphate as adjuvant.
It was also shown that the highest antibody titer followed when the primary and secondary injections were given six weeks apart. The immune response was however of short duration and not boosted by a third injection.
Immunized sheep were well protected against a lethal infection but if they overcome the primary challenge, abscesses still develop in the lungs.
It has also been established beyond doubt that the antigen which induces immunity is an integral part of the cell wall. Evidence was gained that the immunity is mediated through serum antibodies and is not of a cullular nature.
6. PASTEURELLOSIS
Sporadic cases of pasteurellosis were encountered in all Regions, especially in young lambs, but also in calves and pigs.
According to the Onderstepoort Research Institute a survey has shown that apart from Pasteurella multicida types A & D, and P. haemolytica types 1, 4, 6 & 7 which are already incorporated into the vaccine, P. haemolytica types 5 & 8 are frequently associated with disease.
In order to incorporate these two strains in the vaccine as well, a method had to be found whereby the vaccine could be concentrated. This was accomplished by sedimenting the bacteria with 4% polyethylene glycol at pH 7.0. This procedure does not adversely effect the potency of the vaccine. Final experiments are still being done before this new technique is used for routine production.
7. TETANUS
Only sporadic cases of Tetanus were recorded. In the majority of instances cases occurred after castration or tail-docking of lambs by the elastrator method, but from Calvinia cases in a few horses and one pig were reported.
8. COLIBACILLOSIS
Escherichia coli infection remains one of the major causes of mortality in young stock, with colisepticaemia in lambs and colibacilosis [white scours] in calves recorded in most ports of the Republic.
The Research Institute states that experiments with a dead polyvalent vaccine showed that a single injection given 2 –3 weeks before calving produces a good antibody response. The antibodies thus induced are very effectively transmitted to calves and lambs through the colostrum. 22/…
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Considerable quantities of vaccine have already been produced and will be issued in the near future. All batches have surpassed the standards which were laid down.
9. LEPTOSPIROSIS
At the Investigation Centre, Stellenbosch, the specimens tabulated below were examined during the year:-
SPECIES NO. OF SPECIMENS POSITIVE NEGATIVE
Cattle 3 394 15 3 379 Pigs 263 59 204 Sheep 7 - 7 Horses 49 14 35 Dogs 42 35 7 Other Animals 17 - 17
Although cattle, pigs, horses and dogs were found positive to a wide range of serotypes, clinical syndromes attributable to leptospisal infections were encountered only where animals were kept under conditions totally lacking in hygiene.
According to a report from the Research Institute, the Hopps haemagglutination test which is used for human sera was found to be unsatisfactory for use with animal sera. Also one trial with experimental monovalent Leptospira pomona vaccine showed that it was equivalent to U.S.A. standards. The vaccine was produced in a medium which contained sheep serum in stead of the more expensive rabbit serum. The vaccine will be issued in the near future.
10. VIBRIONIC DYSENTERY OF PIGS
In the Natal Region this condition appears to have established itself as an important erosion disease. Infection is easily controlled by appropriate treatment and adequate hygienic measures.
11. PSEUDOMONAS INFECTION
This condition appears to have occurred on a very much reduced scale, with only comparatively few cases of bovine mastitis due to this organism, and an occasional case of middle ear infection on farms where it has established itself.
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12. LAMB DYSENTERY [“BLOEDPENS”]
Isolated cases were reported only from the Estcourt area of Natal.
13. ACTINOBACILLOSIS AND ACTINOMYCOSIS
A few sporadic cases of infection with these organisms were recorded, but it did not present any real problem.
14. STAPHYLOCCOCCUS AUREUS
According to Regional Reports, S. aureus is the major cause of both bovine and ovine mastitis in the Natal, O.F.S. Winter Rainfall Regions. In the latter region it is also responsible for many cases of navel ill and general septicaemia conditions in lambs.
Research workers at Onderstepoort state that it has previously been reported that rabbits can be immunized against skin infection by repeated injection of large doses of vaccine. The same can also be accomplished with smaller doses and it has been proven, that the immunity is induced by the bacterial cells and not by extracellular products.
There is apparently no correlation between any serological test, the opsonin index and actual immunity.
[4] PROTOZOAL DISEASES
1. GENERAL
Although it is surmised that Eperythrozoon ovis and Anaplasma ovis both under certain circumstances appear in sheep in the southern Free State, it has so far not been possible to establish either of the organisms in blood smears. Where for no apparent reason sheep lose condition, the possibility of these infections is taken into account.
2. BABESIOSIS
In the Eastern Cape, Eastern Transvaal, Natal and Transvaal Regions, Redwater in cattle took its usual toll. In the Highveld and O.F.S. Regions sporadic outbreaks were recorded.
In the Natal Regional Report the following is emphasised: Since the eradication of East Coast Fever in 1954, farmers have adopted a laissez-faire attitude towards ticks, with irregular dipping and under-strength dipwashes the order of the day. Ticks and tick-borne diseases have increased to such an extent that in the majority of areas Redwater has become the greatest single cause of mortality in adult cattle. Cases are quoted of 90 head being lost in 6 months on one farm, and another owner losing 60 cattle within 5 days.
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The interesting fact is also mentioned that the ratio of Babesia bigemina to B. bovis cases varies from 9:1 in Port Shepstone area to 4:1 in Estcourt. A similar tendency is found in all other areas in Natal.
Biliary Fever in dogs was prevalent in all ports of the country. Only isolated cases of Equine Biliary Fever were reported.
3. ANAPLASMOSIS
Anaplasmosis cases occurred widespread in the Republic, but the disease did not constitute a serious problem in any area.
Vaccine issues by Onderstepoort and Allerton amounted to 452 697 and 48 622 doses respectively, the total issue showing a decrease of 17 compared to the previous year.
4. BESNOITIOSIS
From the endemic areas, the Natal and Transvaal Lowveld, the North Western O.F.S. and the adjacent Transvaal districts, no increased incidence of further spread of Elephant Skin Disease is reported.
Field trials in connection with the vaccine evolved by research workers at Onderstepoort are still in progress in various affected herds.
5. COCCIDIOSIS
Sporadic outbreaks of coccidiosis, in a small percentage of cases accompanied by severe losses, were reported in calves, poultry, lambs and rabbits. In the case of calves, the majority of outbreaks occurred where hygiene was of a low order, while serious outbreaks in poultry were encountered only in backyard flocks.
In the Kruger National Park, Eimeria zurnii was found to be the cause of death of buffalo calves in aptivity; a pathogenic coccidium of buffalo, not previously described, was isolated and named E. synceri; a protozoon not previously described, and isolated from the uterus of impala, was named E. Neitzii.
In connection with the ehacma baboon papio ursinus [Kerr, 1992], research workers at the Veterinary Institute report that mild infections with Isospora ursini n.sp. were found in 3 out of 20 baboons examined in the Kruger National Park. This is apparently the first record of coccidia in the baboon. The parasite is rather similar to I. hominis of man and there may be a relationship between the two. Since baboons are used extensively these days for experimental purposes the possibility of this organism causing illness in captive baboons should be borne in mind.
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Research workers at Onderstepoort also state that it has been determined that E. chinchillae, the cause of coccidiosis in chinchillas, occurs naturally in striped mice in the Pretoria district. Seeing that other rodents are also susceptible to artificial infection the organism is probably more prevalent than is suspected at the moment. Wild rodents which enter chinchilla houses are therefore probably responsible for the introduction of the disease.
[5] VIRUS DISEASE
1. BLUE TONGUE
Presumably due to the dry conditions prevailing during the early summer months, very few outbreaks were experienced in the majority of Regions, while in the Natal and Winter Rainfall Regions no serious losses occured.
The demand for vaccine decreased from 22 020 800 doses during the previous twelve months to 19 252 450 during the current year.
The Veterinary Institute, Onderstepoort points out that the fete of bluetongue virus in winter in unknown. A knowledge of where bluetongue virus can be found in winter may lead to a alternative approach to bluetongue control which at present relies on the annual immunization of sheep.
Light trap catches over 7 years at Onderstepoort showed that Culicoides adults were active on accasional winter’s nights and in some years remained active throughout the winter. Culiccides were also shown to survive refrigerator and winter temperatures for up to 53 days.
Bluetongue virus is present in Culicoides at the end of May just prior to their disappearance of decrease in numbers with the start of the cold weather. In the U.S.A. this virus remains in C. variipennis for at least 26 days at 24 ± 20C and can be expected to persist longer at winter temperatures. Bluetongue virus may therefore be able to survive short winters in infected Culicoides midges while warmer nights in some years may allow midges to fly and feed and so reinfect new hosts.
Bluetongue virus was thought to disappear completely in Culicoides from June until the end of November but it has now been shown that the virus is present at the beginning of October but in so few midges that over 153 000 collected over a period of 14 days had to be tested to show the virus.
2. HORSESICKNESS
Mortality in vaccinated horses was reported from the Dundee and Vryheid areas, but generally it may be stated that very few cases of horsesickness were recorded.
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According to workers at Onderstepoort, African horsesickness is a disease of equines in Africa which has recently spread as far as India yeat the method whereby it is transmitted has still to be explained satisfactorily since no multiplication of the virus has been shown in the mosquito species so far considered to be vectors.
Laboratory-reared Aedes aegypti, Culex pipiens fatigans, and trap-caught Culicoides midges were fed on African horsesickness virus solutions and on infected horses. The virus could not be recovered from these insects from 1 tot 40 days after feeding. The successful artificial infection of mosquitoes with horsesickness virus and biological transmission of the virus by Culicoides spp. Recorded by other workers could not be repeated.
Multiplication of horsesickness virus in these insects will have to be shown before existing claims of successful biological transmission can be accepted completely.
3. HEARTWATER
This disease took its usual toll in all the recognised Heartwater areas of the country, where it remains one of the major problems of both the small stock and cattle farmer.
Workers at the Veterinary Research Institute state that hitherto it has been accepted that the parasite that causes heartwater in ruminants multiplies in the cells of the bloodvessels to be liberated into the blood stream. Experimental evidence has now been obtained that the parasite also multiplies in lymph nodes and probably in other organs containing tissues of the reticulo-endothelial system. The parasite was demonstrable in lymph nodes prior to its appearance in blood vessels.
Preliminary studies on the immunity in heartwater indicate that serum antibodies play little or no role in the resistance against this disease.
During the year electron microscopic studies were carried out on the causal organism of the disease and further knowledge was gained on the morphology and ultra structure, which appear to indicate a reconsideration of the taxonomy of the Cowdria.
At Onderstepoort Institute, female Amblyomma hebraeum ticks in various stages of engorgement were removed daily from a heartwater infected sheep during the reaction phase before the animal died. Salivary gland material was collected from these ticks, according to a method evolved at Onderstepoort, for biological and biochemical examination. Intravenous injections of this material into susceptible sheep produced heartwater which was confirmed at
post mortem examination. Histological examination of salivary glands from these female ticks revealed the presence of organisms resembling Cowdria
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ruminantium. Isolation of this pathogen could lead to its culturing and characterisation, which may possibly contribute to improved methods of control of the disease.
4. EPHEMERAL FEVER
Only isolated cases of Three Day Stiffsickness were encountered during the year, with exceptional fatalities reported from the O.F.S. and Transvaal Region.
5. RIFT VALLEY FEVER AND WESSELSBRON DISEASE
After an absence of many years, Rift Valley Fever made its re-appearance in widely separated parts of the Republic. Serious losses due to mortality in lambs and abortions in cattle occurred in the districts of Standerton, Frankfort, Kroonstad Koppies and Odendaalsrus, while abortions and isolated mortalities were recorded in the North Western Cape district of Vryburg, and in Lower Umfolozi, Natal.
No cases of Wesselsbron disease were reported.
6. “SNOTSIEKTE”
One case of Bovine Malignant Catarrh was confirmed in each of the Highveld, Transvaal and Winter Rainfall Regions. In the latter instance the affected bovine had been in contact with blue wildebeest in a private zoo.
7. RESPIRATORY DISEASES OF POULTRY
In connection with Infectious Bronchitis research workers at the Institute state that as reported last year, work is progressing on an experimental live attenuated vaccine against this disease and a further 60 000 hens were inoculated. This brings the total number of doses tested to 400 000. None of the vaccinated birds have hitherto suffered from infectious bronchitis and the vaccine appears to hold great promise.
8. FOWL POX
No doubt due to the dry conditions prevailing throughout the country, only isolated outbreaks of Fowl Pox were reported.
In all cases use the vaccine gave excellent results.
9. “JAAGSIEKTE”
Even in the recognised “Jaagsiekte” areas, where its apparent spread caused great alarm in previous years, the incidence of this disease was very low this year. 28/…
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10. VIRUS PNEUMONIA OF PIGS
Although suspected cases of this disease were found at abattoir inspections, no confirmed cases were reported.
11. EQUINE RHINO-PNEUMONITIS
Several cases of Rhino-pneumonitis in horses in the Durban area were reported by a private practitioner.
[6] INFERTILITY AND VENEREAL DISEASES
1. GENERAL
The personnel of the Artificial Insemination and Reproduction Section of the Investigation Centre at Onderstepoort examined 27 herds of cattle and 1 flock of goats with reproductive disorders. State Veterinarians throughout the country investigated problems of infertility and low fertility in herds and flocks.
A general finding is that many of these breeding problems are due to infectious causes, but to errors in feeding, deficiencies and imbalances in the total ration, and bad management practices on the part of the owner.
2. VIBRIOSIS
During the year 1 177 and 6 232 specimens respectively were examined for Vibriosis at the Central and Regional Investigation Centres, with an overall positive finding of 6.2%.
The latter cannot be regarded as indicative of the incidence in the national herd, as these specimens were not taken at random, but emanated from herds with breeding problems. Nevertheless the disease occurs widespread and appears to be the most important single infectious cause of infertility in cattle.
Research workers at Onderstepoort report that a Vibrio fetus strain which grows more profusely than standard strains has been isolated and may prove to be very useful for vaccine production.
3. TRICHOMONIASIS
Trichomonas infection has been recorded over the years in herds scattered over the country, but the incidence remains very low, and the disease cannot be regarded as of any great importance.
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4. INFECTIOUS INFERTILITY
Of the 1 503 specimens examined for Infectious Pustular Vulvovaginitis and Infectious Bovine Rhinotracheitis at the Onderstepoort Investigation Centre, 419 proved positive, and 557 of the 1 323 examined at the Allerton Investigation Centre, giving an overall incidence of 34.5%.
This is not a reliable indication of the national incidence, as specimens were derived mostly from herds with a history condition is widespread.
According to Regional Reports, clinical manifestations are not often seen in herds in which IPV/IBR is present, so that the significance of this infection in reproduction has not yet been established.
[7] DISEASES OF CALVES
1. WHITE SCOURS
As in previous years, Escherichia coli infections caused heavy losses throughout the country, especially in dairy herds where hygiene and management practices were not of a sufficiently high standard.
2. PARATYPHOID
As a result of the availability of the very efficacious vaccine produced at Onderstepoort, this disease has lost much of its former importance as a killer and stunter of young calves.
Outbreaks causing serious losses were however still reported during the year from all parts of the Republic.
3. COCCIDIOSIS
Only isolated, small scale outbreaks were recorded, so that the disease is not of any economic importance in the country.
4. CALF DIPHTHERIA
With very few exceptions, only isolated cases occurred in sporadic outbreaks throughout the country.
5. SWEATING SICKNESS
In all the enzootic areas except the Transvaal Region and the Mafikeng district, the incidence of this disease was very low during the year.
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[8] INTERNAL PARASITES
Largely on account of the prevailing dry conditions throughout the country, internal parasitism did not qualify again as one of the main erosion diseases.
In all the Regions tapeworms in young stock and roundworms were the most important; in parts of the Highveld and O.F.S. Regions, conical fluke was a problem, while liver fluke was of importance in the Highveld and certain areas of the Winter Rainfall Region; in portions of the latter, lungworm infestation played an important rôle; measles in cattle led to severe losses in Natal, Eastern Transvaal and Transvaal.
In the course of surveys and in diagnostic services to farmers, State Veterinarians in all areas conducted post mortem examinations and examined faeces samples to elucidate problems of internal parasitism. Extension work in all its forms, covering all aspects of parasite control, was carried on throughout the year.
The examination for trichinosis of specimens from pig carcases slaughtered at various abattoirs was maintained during the year. No positive findings were made, but of 1 108 specimens from 14 different species of game in the Kruger National Park, one hyena proved positive.
At the Research Institute, Onderstepoort, a new procedure has been developed to test the efficacy of anthelmintics against lungworm of sheep. Procedures to test the efficacy of anthelmintics against roundworms of cattle are being developed.
To determine the effect of anthelmintics on wool production and weight gain of sheep, research workers used two groups of ewes at Memel, O.F.S. The group treated with a broad spectrum anthelmintic gained 3 1b. of weight and 1 1b. of wool more than the group treated with drugs of limited efficacy.
In an effort to determine the aetiology of gut tie in sheep, twelve merino sheep were infested with 12 000 infective larvae of nodular worm and typical stretching symptoms developed.
The role of this parasite in this syndrome will be further investigated.
In work on the viability of the Bilharzia worm, researchers infested sheep by different routes to determine which would result in the highest percentage of development.
It was found that infestation through the skin was most effective.
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In studies on Schistosoma infestation at Onderstepoort, six healthy sheep were artificially infested, through skin exposure, with graded doses of cercariae of Schistosoma mattheei. By means of laboratory tests the development of lesions due to the disease could be monitored at weekly intervals, so as to shed light on the changes responsible for illness and death.
In the blood itself there was every avidence of anaemia and the plasma lost a lot of its albumin fraction. Beta and gamma globulin, however, increased and more than compensated for loss of albumin.
The tests showed only very little damage to the liver cells but the through-flow of blood was severely interfered with by the parasites and the local reaction caused by their presence.
The metabolism of these sheep, in general, was not affected.
The loss of blood of faeces of sheep infested with bilharzia was studied, and the use of radio-isotopes showed that infested sheep may loose up to 30 ml blood per day in the faeces.
When treating an animal it is extremely important that the amount of blood lost is determined.
Reports on the removal of bilharzia eggs from the tissues of infested sheep, researchers state that these worms lay their eggs in the bloodvessels of the host. The eggs must pass through tissues to be voided with the faeces.
Up to 20 million eggs have been recovered mainly from the intestinal wall, of an infested sheep.
In investigations into bilharzia, the larval stage was immobilised to examine its finer structure. A new staining method can distinguish between living and dead cercariae.
A reliable procedure for counting cercariae has been developed. In this process 340 000 carcariae were counted and the data analysed statistically.
[9] EXTERNAL PARASITES
Reports indicate that ticks created relatively fewer problems in the Eastern Transvaal and O.F.S. Regions, but in the other areas the position was not so favourable. Australian itch in sheep and lice infestation in both sheep and cattle occurred widespread in all Regions; while the former was readily controlled, the latter most decidedly caused losses during the winter months. Sheep nasal fly was troublesome in the East Griqualand area of Natal and the Highveld Region.
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The Onderstepoort Research Institute reports that a tick control survey is being carried out since January 1970 in the districts of Port Shepstone and Ixopo, in collaboration with the Division of Veterinary Services. The species of ticks present at certain selected dipping tanks as well as the dip wash are being recorded for the possible existence of resistant strains, which may no longer be under effective control. Redwater is a serious problem in these areas, in spite of controlled dipping, and is being investigated with a view to finding a solution. The presence of Boophilus microplus and the relative absence of B. decoloratus observed with the survey requires further attention, in view of the rôle of B. microplus as a resistant species in other parts of the world.
In connection with the area to be affected by the Orange River Development Scheme, research workers state that a survey was carried out during 1969 on 35 farms in the Bethulie, Smithfield, Albert, Venterstad, Philippolis and Colesberg Districts. The aim was to determine the tick species present, and their relative abundance, for comparision with the position later when parts of the area have been flooded.
Whenever possible quarterly collections were made, mostly from cattle and sheep, and ten species of ticks were recorded.
By far the commonest species is the spinose ear tick, Otobius megnini, which is present on the majority of the farms visited. Its incidence is particularly high at the eastern end of the survey area. Two species of bont-legged ticks are also prevalent: the coarse bont-leg, Hyalomma marginatum rufipes, was collected on all but one farm while the smooth bont-leg, H. truncatum, occurs mainly to the west. The Karoo paralysis tick, Ixodes rubicundus, was found in small numbers on sheep on eight farms, scattered throughout the area, in the winter. Several species of brown ticks [Rhipicephalus spp.] also occur but usually in very small numbers. The yellow dog tick, Haemaphysalis leachi, was collected from the only two dogs and a cat which were examined.
With reference to work on biting midges, it is reported that the survey of the Orange river from Goedemoed near Aliwal-North to Kalkwerf close to Upington has yielded 349 sixthstage Simulium larvae, 771 pupae and 1 168 adults. Two species have been encountered, viz. S. chutteri and S. gariepensis of the S. griseicolle group. S. gariepensis was initially confused with S. griseicolle [Annual report 1968/69].
S. chutteri became a serious pest along the Vaal river in the past and had to be controlled. It may likewise benefit from the ecological changes being caused by the building of the series of dams in the Orange river.
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Since no research work has been done on S. gariepensis little is known about the life cycle and habits of this midge. It is possible that S. gariepensis depends on birds for a blood meal like its close relative S. griseicolle.
The Veterinary Research Institute reports that during 1969 a strain of the green blowfly, Lucilia cuprina was brought to Onderstepoort from Riversdal, Cape, and it was found to be resistant to insecticides when compared to a susceptible strain. This twenty five fold resistance is reduced to the same level as that of the Onderstepoort strain in the absence of insecticide selection. When insecticide selection is re-introduced it has been found that a nine fold resistance develops after three generations.
At the beginning of 1970 a second strain [Riversal II], was obtained which showed a fall in resistance from 25 to six fold and has remained at that level for the past ten generations. Further investigation should indicate whether this resistance is genetically linked or simply a vigour tolerance, and in which way blowfly infestation can be more efficiently combatted.
4. OTHER VETERINARY RESEARCH
[1] BASIC RESEARCH
1. MYCOPLASMOSIS OF POULTRY
A reliable haemagglutination test has been developed for the diagnosis of infectious synovitis [Mycoplasma synoviae]. It is now possible to differentiate between chronic respiratory disease [Mycoplasma gallisepticum] and infectious synovitis with the aid of the haemagglutination-inhibition test.
2. INFECTIOUS CORYZA OF POULTRY
This disease has recently emerged as an important economic problem on certain egg-producing poultry farms. The aetiological agent, Haemopilus gallinarum, was isolated for the first time in South Africa. A comparative therapeutic study revealed that the carrier state of recovered birds could not be eradicated by any of the drugs used. Sulphachlorpyrazine, sulphadimidine and the combination sulphachlorpyrazine-straptomycin were very effective for the treatment of the disease and were the only drugs that prevented spread of the disease during therapy.
3. HERPES VIRUS OF PIGEONS
A herpes virus which causes hepatitis in pigeons has been isolated for the first time in South Africa.
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4. RESEARCH ON BLUETONGUE AND HORSESICKNESS VIRUSES
Good progress was made with the programme which is aimed at the determination of the basic properties of this group of viruses. Further studies on the nucleic acid components of the viruses were conducted. Utilizing biochemical and electronmicroscopical techniques, it could be shown that this component, which carries the genetic characteristics of the virus, existed in a segmented form.
Simultaneously a start was made to study the protein portion and methods are at present being developed to separate the various components and to correlate these with nucleic acid segments. The purpose of the study is to obtain a clearer understanding of the structure and functions of the different parts of the virus, which could later possibly lead to specifically directed changes thereof e.g. to change specific properties of viruses.
Besides the work on the virus itself considerable progress has already been made on the study of the effect of the virus on the cell in which it grows. It has, for instance, been determined that bluetongue virus when it penetrates the cell, drastically inhibits cellular protein synthesis even in the absence of any virus multiplication or virus-specific synthesis. This effect, which explains some of the disease symptoms of the virus, is being further investigated.
5. ISOLATION OF EQUINE CYTOMEGALOVIRUSES
Various equine herpesviruses, including equine rhinopeumonitis virus and spontaneous isolates from horse kidney cell cultures were included in a comparative study. Certain of these viruses exhibited cytomegalovirus-like properties, and hence the object of this comparative study was to define more closely equine cytomegaloviruses.
The viruses were compared for ultrastructural morphology, growth in various cell cultures and sensitivity to certain agents such as trypsin.
The results of these investigations indicated that equine herpesviruses could be subdivided into three separate subgroups. The first of these included the classical herpesviruses such as rhinopneumonitis virus. The second subgroup was composed of viruses which showed distinct cytomegalovirus properties such as a very slow growth rate with the production of relatively low titres of infective virus, a very restricted in vitro host range and the formation of dense basophilic intranuclear inclusion bodies associated with marked margination of chromatin. Electron microscopic examination revealed a high percentage of empty or partially empty particles. The viruses in this group were also remarkably resistant to the action of trypsin.
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The third group was composed of viruses which shared certain properties with both the classical herpesviruses and the equine cytomegaloviruses.
6. REACTION OF THE ADRENAL CORTEX OF CATTLE TO HALOTHANE ANAESTHESIA
This study has been complete and the results were published during the current year. Certain important breed differences have been detected by the determination of plasma cortisone, blood sugar, sodium, potassium and other haematological tests.
7. RESEARCH ON THE CAUSE AND CONTROL OF GEELDIKKOP AND GEELSIEKTE [ENZOOTIC ICTERUS] IN SHEEP
Geeldikkop and geelsiekte are basically diseases in which the membranes of cells of various organs in the body are seriously damaged by, amongst other, a low grade selenium intoxication. When affected animals are subjected to any form of stress, for instance sudden changes in the grazing or the environmental temperature, transport over long distances or various infections, then passage of certain vital body constituents across these membranes is affected eatastrophically. The result is the production of a disease picture which follows failure of liver and kidney function, damage to the heart and a breaking up of the red blood cells.
Research during the year under review has been directed towards study of the following points of great interest:
[a] transport of minerals such as sodium, potassium and calcium across the red blood cell membranes of affected sheep;
[b] by use of iron by the sheep in correcting the anaemia which develops in the two diseases;
[c] the absorption and and use of copper by the sheep;
[d] the transport, for purpose of elimination from the body, of waste substances across the liver and kidney cell membranes.
[e] the development of electrocardiographic techniques for detecting damage to the heart in sheep;
[f] the development of methods for determining the state of activity of organs which regulate the normal physiology of the animal, e.g. the thyroid, and
[g] the control of body water in animals living in arid areas.
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The results have been most gratifying and we are now in a position to formulate effective measures of treating the anaemia in affected animals and we are also able to see quite clearly how excessive accumulation of cooper in the bodies of these animals occurs following disturbances of transport of this mineral across the intestine cell membranes. Thyroid function can be rapidly assessed in the sheep by an easy accurate method just developed. Electrocardiography promises to be a most useful tool in studying heart conditions in the sheep and should have considerable impact in work on other diseases of sheep and cattle, e.g. “gousiekte”, “gifblaar” – and “tulip” – poisoning.
8. RESEARCH ON DIGESTION AND METABOLISM IN RUMINANTS
Researches continue to be concentrated on the digestion of high roughage diets and the metabolism of the digestive end-products of these by Merino sheep, since the importance of feeding these diets to ruminants has now gained world-wide recognition. The digestion of these diets is carried out mainly by the fibre-digesting bacteria of the rumen, and the ecological studies of these bacteria at Onderstepoort are the most advanced in the world. For this reason one of the researchers advises the International Union of Nutritional Sciences on this crucial aspect. The present microbiological researches are aimed at finding out why different fibre-digesting bacteria predominate on the different diets. This knowledge is essential tot the understanding of how to supplement roughage diets to get the best, and at the same time, the most economic results, and how this influences the digestive endproducts available for the nutrition of the sheep. Of all the fibre digesters, Ruminococcus albus is one of the most active, and the indications are that when it predominates in the rumen at high levels, the rate of fibre digestion is increased and hence the roughage intake of the host animal. This bacterium predominates naturally when lucerne hay is fed, but it can also be made to do so for poor veld hay [3% crude protein] when judicious supplements containing non-protein nitrogen [3%], branched-chain volatile fatty acids [less than 2%] and a little extra sulphur are fed with this hay.
The microbiological investigations are followed up by studies on the utilization by the host animals of the digestive end-products made available for its nutrition by the rumen bacteria.
It has been known that the level of the vital blood glucose is only half that of monogastric mammals. The results of the recent investigations into the sources of glucose to ruminants indicate that the ruminant overcomes this shortage not only but the known greater use of volatile fatty acids as a source of energy, but also by employing certain of these acids e.g. propionic acid as an alternative starting substance for the synthesis of other vital compounds like glycerol necessary for the deposition of fat.
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At the same time part of the research effort is being directed to the development of techniques required to break through into the various areas under investigation. These include the experimental-surgical preparation of physiologically normal sheep with indwelling venous catheters into and out of various organs like the liver so that the metabolism of the digestive end- products can be measured under the sheep’s own hormonal control.
[2] MISCELLANEOUS RESEARCH AND PROJECTS
The registered project on investigation into all the aspects of ill-thrift in sheep in the Port Elizabeth coastal region, was continued.
Work on Actinobacillus seminis infection in sheep was continued during the year at Middelburg, C.P., while various aspects of internal parasitism were investigated at Beaufort-West.
At Mafikeng further studies on the ecology of viverridae were carried out.
The severe draught seriously handicapped work on the problems of the ostrich industry being carried out at Oudtshoorn.
Numerous projects covering many aspects of the ecology, utilization and diseases of game were initialed or continued in the Kruger National Park.
[3] RESEARCH ON DISEASES OF GAME
From the Kruger National Park it is reported that for the first time the ticks Rhipicephalus tricuspis and Argas tholloni were found, on reedbuck and elephant respectively.
According to research workers at Onderstepoort Cytauxzoonosis, a protozoal disease transmitted by ticks and previously only diagnosed in the eland, duiker and kudu has now also been confirmed in the giraffe. This is considered important with a view to the increased interest in game farming, especially browsers, both as a source of extra income and the prevention of bush encroachment.
An important virus disease in the lungs of elephants and a uterine protozoal disease in the impala was also found. Studies on these diseases are continuing and the susceptibility of domestic animals is being determined.
A study of the pathology of the baboon [Papio ursinus] from the Kruger National Park was commenced during the year, with the object to attemp a detailed analysis of the disease spectrum of this species as it occurs in its naturals habitat. The study is regarded as being important because the baboon is increasingly being used in medical research and hence its disease
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potential should be known. This aspect is of importance also with regard to the translocation of the African chacma baboon to foreign countries and its consequent possibility of introduction of “exotic” zoonoses.
To date the autopsy of 60 baboons has led to the following significant results:-
1. Identification of coccidiosis infection [Isospora papionis]. 2. Identification of 2 new species of mites. 3. Recognition of a “capture myopathy” syndrome and its relation to adrenal hemorrhage. 4. Isolation of an adenovirus with oncogenic properties in newborn hamster tissue cultures. 5. Identification of cytomegalic inclusion bodies in the mandibular salivary glands. 6. Study of Sarcosporidiosis with a possible predilection for certain muscle groups. 7. Incidence of several gastro-enteric metazoan parasites.
A survey was undertaken in the Kruger National Park of the various diseases and parasites of the buffalo under natural conditions. This was done with a view to the buffalo as a source of food, the protection of these animals against infection and the possible danger of these diseases and parasites to domestic animals. One of the most important findings was the fact that approximately 97% of the buffalo were carriers of the parasite which causes “corridor disease” [buffelsiekte]. This parasite causes symptoms only in the calves. Although bilharzia was also confirmed in 62% the lesions were not very severe. Apparently the buffalo is not susceptible to besnoitiosis [Olifantsvelsiekte].
[4] BLOOD GROUP STUDIES
In a project carried out in the Kruger National Park, during the course of which investigations were done on 359 blood specimens, it was found that:-
[a] breeding in the elephant is heterogeneous; inbreeding therefore does not occur in the elephant; [b] the above applied also to the blue wildebeest; [c] the impala shows a very marked heterogeneity, indicating that no inbreeding whatsoever occurs; [d] buffalo show marked signs of homogeneity; herds in different parts of the Park are homogeneous herds, indication that there is no contact between the various herds, and the danger of inbreeding definitely exists.
5. VACCINE PRODUCTION
During the past year there has been a substantial decrease in the demand for vaccines. Only 95 470 083 doses of 28 different vaccines were issued compared with more than 108 million the previous year. This decrease of
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12% can be attributed mainly to the severe drought conditions which prevailed in certain parts of the country. The issues of bacterial vaccines was reduced by 10% mainly due to a decrease of nearly 7 million doses in the demand for enterotoxaemia vaccine. The issues of virus vaccines was reduced by 16% as a result of a decrease in the demand for bluetongue vaccine [nearly 3 million doses] and Newcastle disease vaccine [more than 5 million doses]. Due to the outbreaks of Rift Valley fever in Rhodesia and Mocambique during the previous year and the confirmed outbreaks in the Republic during the pas year, the issues of Rift Valley fever vaccine increased by more than a million doses to a total of 3 540 850 doses during the year. The vaccine against Wesselsbron disease which was previously an integral part of Rift Valley fever vaccine, is now issued separately. A total of 1 148 650 doses was issued during the past year. The vaccine issues for the last three years are given in the accompanying tables.
In addition to vaccines, the Institute has prepared the usual diagnostic antigens. The demand for tuberculin has increased considerably since the tuberculosis eradication scheme has been put into operation.
BACTERIAL VACCINES 1967/68 1968/69 1969/70
Enterotoxaemia 38 535 200 43 155 850 36 355 800 Bloedpens 426 500 302 700 257 580 Lamsiekte 3 899 285 4 310 445 4 553 270 Anthrax 8 744 550 11 122 170 11 559 490 Black Quarter 3 854 600 4 907 886 4 842 232 Swelled Head of Rams 2 350 8 700 6 600 Brucella [Bovine] 707 784 943 912 844 277 Brucella [Ovine] 351 190 422 100 352 600 Fowl Typhoid 1 389 000 1 643 400 1 337 800 Calf Paratyphoid 426 662 406 688 290 880 Tetanus 58 760 83 830 69 190 Corynebacterium pyogenes 188 540 179 940 145 700 Corynebacterium ovis 377 210 325 400 276 400 Pasteurella 446 520 378 280 402 420 Colibacillosis [Calves] - 1 376 1 720 Colibacillosis [Lambs] - 6 550 7 500
15 VACCINES 59 398 151 68 199 228 61 303 459
VIRUS VACCINES 1967/68 1968/69 1969/70
Bluetongue 21 185 200 22 020 800 19 252 450 Fowl Pox 5 832 500 5 908 700 5 154 000 Pigeon Pox 522 980 324 100 459 200
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VIRUS VACCINES 1967/68 1968/69 1969/70
Rabies 215 469 215 695 197 730 Lumpy Skin Disease 1 241 579 563 367 441 973 Horsesickness 120 817 118 070 110 526 Distemper 15 053 17 216 16 078 Distemper [Mink] 2 990 5 070 4 360 Newcastle Disease 19 531 970 8 409 100 3 260 600 Rift Valley Fever 16 950 2 445 350 3 540 850 Wesslesbron - - 1 148 650
10 VACCINES 48 685 508 40 027 468 33 586 417
OTHER “VACCINES” Heartwater blood 49 612 61 458 57 310 Anaplasmosis 413 626 460 089 452 697 Redwater 47 108 54 089 70 200
3 VACCINES 510 346 575 700 580 207
Grant Total 28 Vaccines 108 594 005 108 802 416 95 470 083 In addition to the above vaccines, the Research Institute also prepared the diagnostic aids listed below:
PRODUCT NUMBER OF UNITS 1967/68 1968/69 1969/70 B.W.D. Antigen 42 475 40 795 47 360 Brucella Ring Test Antigen 774 1 755 633 Mallein 170 - 70 Tuberculin [Bovine] 194 216 286 110 686 550 Tuberculin [Avian] 57 140 127 630 283 130
At Veterinary Investigation Centres the following vaccines were produced:-
Anaplasmosis 48 622 doses Redwater 17 281 doses Heartwater 6 830 doses Wart Vaccine 21 152 doses “Vuilbek” [Contagious pustular dermatitis] 452 doses
At the Stellenbosch Investigation Centre 14 650 ml of Leptospirosis antigen [12 different strains] was prepared.
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6. OTHER VETERINARY SERVICES
[1] DIAGNOSTIC SERVICES
The programme of equipping five investigation centres namely Onderstepoort, Allerton, Stellenbosch, Middelburg C.P. and Windhoek S.W.A. with more advanced facilities and apparatus, referred to in the previous report, was continued during the year. More advanced investigational work, beyond the scope of the other 20 centres, can therefore be undertaken at these five. Where highly specialised investigational or research work is required to elucidate any problem, the matter is referred to Onderstepoort with its teams of researchers and sophisticated facilities.
During the year good progress was made with the erection of two investigation centres for Bantu veterinary services, one at Cwaka [Zululand] and one at Sibasa [Northern Transvaal]. Both these centres should be equipped and functional in the near future.
In addition to playing an important rôle in the promotion of animal health by means of extension work, disease surveys, the implementation of disease eradication schemes and co-operation with the Research Institute in research projects, State Veterinarians at Investigation Centres and other stations throughout the country, did a great deal of diagnostic work.
In the course of diagnoses, the post mortem examinations listed below were performed during the year:
Cattle 1 030 Sheep 1 988 Goats 43 Equines 9 Pigs 517 Dogs 89 Cats 60 Poultry 22 489 Other animals 107
The following laboratory examinations were carried out at Regional Investigation Centres:
Brucella agglutination tests 74 268 Brucella milk ring tests 17 135 Vibriosis 6 232 Leptospirosis 6 806 Actinobacillus seminis 9 533 Antibiograms 492 Skin scrapings 260 Faeces examinations 13 361
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Milk [mastitis] 4 897 Semen 3 810 Haematological 18 731
Biochemical 14 496 Toxicological 518 Bacteriological 3 691 Virological 1 323 Biological 211 Histopathological 847 Trichinella examinations 43 381 Smear examinations 14 906 234 898
At the Central Investigation Centre, Onderstepoort, the examinations listed below were carried out:-
Brucella agglutination tests 5 844 Vibriosis 1 177 Leptospirosis 1 921 Antibiograme 325 Milk [masitis] 402 Smear examinations 318 Sheath washings 602 Biopsies 276 Bone, blood and carcase meal 172 Clostridia 80 Foeti 69 Organ and swab 1 219 Poultry post mortems 2 105 P.P.L.O. tests 1 242 N.C.D. tests 19
[2] SURVEYS
In the East London Veterinary Area a dip survey was conducted during the year, but this has not been finalized.
Surveys of the calving percentages in selected herds in the Pietermaritzburg and Louis Trichardt areas of the Eastern Transvaal were continued; investigations into Brucellosis in Bantu cattle in the Pietermaritzburg area were completed, and a similar study started in the Lydenburg area; preliminary work has been done on the problem of internal parasitism in Bantu cattle in Pietersburg.
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In conjunction with the Research Institute, IPV/IBR and Vibriosis surveys were continued in the Highveld Region.
Investigations were continued into the seasonal variations of the mineral status of cattle on selected farms in the different ecological regions of Natal. Valuable information has been obtained, and spectacular results have been produced in some instances by the corrective measures advocated.
Many hundreds of dip samples and thousands of ticks were despatched to the Tick Research Section at Onderstepoort from all over Natal in a dip survey which has not yet been completed.
In the Dundee and Vryheid, and to a lesser extent, the Ixopo areas of Natal, the mastitis problem has received special attention, and considerable progress made in controlling the condition in the herds investigated.
Investigations into the incidence of Mucosal Disease and Brucella melitensis in Natal were initialed during the latter part of the year.
Preliminary data collected in a survey of fertility in rams in the Dundee area point to the fact that farmers could themselves eliminate at least 25% of sterile rams from their flocks.
As in previous years, a Nagana survey was conducted in the erstwhile enzootic areas in Natal:
A slight increase of Glossina brevipalpis in the St. Lucia complex was found, and an alarming increase in the Ndumu area.
The Corridor Disease survey of the Hluhluwe Umfolozi Game Reserve complex, conducted in collaboration with Onderstepoort, was completed during the year: of 244 blood specimens sent in from the Hlabisa and Nongoma districts, 17 proved positive.
The investigations by workers at Allerton into perinatal mortality in lambs, have been finalised, and a report presented for publication.
In the O.F.S Region the State Veterinarian, Kimberley, is engaged on surveys on minerals, the incidence of Escherichia coli and Pasteurellosis in sheep, internal parasites in game and Actinobacillosis in rams.
Brucellosis in cattle and infertility in sheep are being investigated in the Ermelo area of the Transvaal.
Surveys on mineral imbalances and deficiencies in selected areas of the Winter Rainfall Region have been completed, and a report is being prepared.
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A project on perinatal mortality in lambs in the Malmesbury area was completed during the year. A total of 360 lambs from 12 farms were presented for post mortem examination. This examination plus the questionnaires completed by breeders indicate that an average of 22.5% of lambs born die before weaning, and 77% of deaths are due to physical causes, of which exposure and starvation are the most important. It is therefore concluded that poor management is the most important single cause of high lamb mortality in this area.
[3] CLINICAL SERVICES
As in the past, State Veterinarians provided clinical services to the public when not prevented from doing so by their official duties, in all the areas where no private veterinary practitioners are available.
Veterinary Services were also provided for all State herds and flocks.
During the year R14 423,95 was collected for clinical services, R5 206,64 for mileage fees and R13 026,99 for vaccines sold by State Veterinary Officers, while laboratory fees amounted to R1 370,93, fees for meat inspection to R19 714,27 and for quarantine stations to R1 602,75.
[4] ARTIFICIAL INSEMINATION SERVICES
Certificates of approval are a prerequisite for the registration of new bulls intended for artificial insemination service, and for the annual re-registration of bulls already standing at A.I. Co-operatives and breeders.
For these certificates the A.I. and Reproduction Section of the Division carried out examinations for tuberculosis, brucellosis, leptospirosis, vibriosis, trichomoniasis and IPV/IBR on 70 A.I. station and 7 breeders bulls. Seven of these bulls proved positive for vibriosis and 11 for IPV/IBR.
Four A.I. courses for persons desirous of qualifying as inseminators were conducted at Onderstepoort, and 56 of the 59 candidates qualified.
In addition to the above, the A.I. Section also presented a short course – 4 days – to 20 farmers at Vryburg, and assisted with a short course presented to farmers at Vryheid, while lectures on infertility and venereal diseases were given at a farmers day at Lydenburg.
At Potchefstroom 16 A.I. courses, attended by 119 persons, were held for farmers wishing to apply A.I. in their own herds.
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In Natal, well attended courses were held at Cedara, Vryheid, Dundee and Ixopo. For Bantu farmers courses were presented at Ixopo, while at Cwaka College a film on A.I. was shown, followed by a lecture.00
At Elsenburg in the Winter Rainfall Region 4 courses were given. These were attended by a total of 58 farmers.
7. HEALTH SCHEMES
[1] BACILLARY WHITE DIARRHOEA
The disruption in B.W.D. testing in the Transvaal Region as a result of the Newcastle Disease outbreak during the previous year, is the major factor in the decrease of certificated flocks in the scheme from 143 during 1968/69 to0 the present 96.
Details of tests performed and certificates issued during 1969/70 are tabulated below:-
TESTS CERTIFICATES FOWLS NUMBER OF REGION FLOCKS TOTAL POS. SUSP. HOLDERS FOWLS Eastern Cape 7 6 642 - - 7 13 721 Eastern Transvaal 1 1 600 - - 1 1 600 Highveld 26 70 028 2 - 23 284 319 Natal 21 339 647 59 3 20 3 145 270 O.F.S 2 5 390 - - 2 6 600 Transvaal 15 107 980 - - 14 195 447 Winter Rainfall 29 263 517 - 68 29 1 073 307 Total 101 794 804 61 71 96 4 720 304
[2] P.P.I.O. SCHEME
The data of tests performed is summarized
CERTIFICATE HOLDERS NON-CERTIFICATE HOLDERS REGION NUMBER NUMBER OF BIRDS FLOCKS NUMBER OF TESTS
Eastern Cape 1 320 - - Eastern Transvaal - - - - Highveld 5 3 413 - - Natal 12 354 370 27 4 381 O.F.S - - - - Transvaal 2 6 300 - - Winter Rainfall 36 76 107 - - Total 56 440 510 27 4 381
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[3] PIG RECORDING AND HEALTH SCHEME
The position has changed only slightly, with an increase in membership from 37 to 40, and involving 19 310 pigs.
8. MEAT INSPECTION
An Animal Slaughter, Meat and Animal Products Hygiene Act [Act 87 of 1967] and the Standing Regulations [G.N. – R3505] promulgated thereunder were implemented on 9th October 1969. The Act and Regulations became applicable in full to seventeen larger abattoirs which are specified in G.N. 3455 of the 3rd October 1969. These Abattoirs provide approximately 75% of the country’s meat requirements.
Exemption of certain sections of the Act was granted in respect of the rest of the Abattoirs in the Republic.
The main object of the Act and Regulations is to improve and maintain a proper standard of hygiene at all abattoirs and meat processing establishments connected therewith, as well as assuring the hygienic transportation of meat.
Another object is to subject all meat sold for human consumption to an efficient inspection service, thus safeguarding public health by assuring that the consumer is supplied with a wholesome article of food.
All Assistant Directors of Veterinary Services were appointed as Assistant Meat Hygiene Officers and the Natal, Winter Rainfall and Orange Free State Regions have in addition the services of a fulltime Regional Meat Hygiene Officer to supervise the implementation of the Act and also provide owners of abattoirs with professional advice.
According to a survey undertaken by this Division, there is a total of R 1 290 Abattoirs in the Republic of which ownership of 381 are vested in Local Authorities and 774 privately owned.
Application for the issue of Certificates of Approval in terms of the Act were received in respect of 347 Abattoirs owned by Local Authorities and 678 by private owners.
In respect of Abattoirs exclusively used for the dressing of poultry and at which more than 3 000 birds per week are slaughtered, 36 Applications for Certificates of Approval were received, while one for the slaughter of Ostriches, one for game and 12 from Abattoirs which serve State-owned institutions.
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Since the implementation of the Act, detailed inspection has been carried out by Officers of this Division at 93 Abattoirs and in the majority of cases it was found that these establishments are obsolete, and hygiene neglected to a variable extent.
Foreign countries are constantly demanding higher standards of hygiene from our exporting Abattoirs, as a result of which there are now only 3 Municipal and 5 privately owned Abattoirs in the Republic and South West Africa which are approved for export of meat to the United Kingdom.
Various abattoirs and meat processing establishments were also inspected by Swiss and Austrian Veterinarians and official approval for the export of meat and meat products form certain establishments have been received from their respective Governments.
This Division is at present providing the meat inspection services at three of these exporting establishments i.e. Heidelberg, Estcourt and Bellville.
At the Skukuza Abattoir and By-products Plant in the Kruger National Park game carcases are processed. Fresh meat is supplied to the Park restaurants, sold to Park employees or used as rations for Bantu labourers. Biltong and dried sausage is produced for sale. Material not fit for human consumption is converted into bone or carcase meal.
The following table gives an indication of the extent of operations at the abattoir:
SPECIES NO. OF CARCASES TOTAL CARCASE WIGHT Elephant 405 578 591 kg Buffalo 665 161 682 kg Zebra 184 36 273 kg Wildebeest 513 64 000 kg Impala 641 15 273 kg Giraffe 2 909 kg Reedbuck 1 32 kg Kudu 1 117 kg
Total 2 412 856 877 kg
Research workers at Onderstepoort point out that biltong is a raw meat product which is prone to various infections of the living animal as well as the carcase. The processing of meat into biltong relies fully on salting and dehydration to control or eliminate such infections. Poisonous chemicals may also contaminate biltong during the preparation thereof.
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An investigation on 60 trade biltong specimens obtained at random in South Africa failed to reveal a single case of misrepresentation of the species of animal concerned. Bacterial counts were, however, usually far in excess of acceptable standards. Two specimens [3.3%] contained salmonellas. Moreover, 45% revealed one, and 98.3% two bacterial indicators of faecal contamination. Salmonella infection causes gastro-enteritis and the most important source is faecal contamination of food. Fungi and yeasts were present on 68.3% of the specimens. They represent an important exonomical problem due to the decomposition the cause and because of their potential health hazard. Hence biltong is unsatisfactory from a hygienic point of view.
The salt and moisture content of biltong varied considerably and was frequently incapable of inhibiting microbial development. Moreover, there was no correlation between the salt and water content of the endproduct and its microbial content. This means that ample opportunity for infection and multiplication of germs exists before biltong is regarded as being ready for consumption.
None of the specimens contained excessive nitrites but 25% harboured small amounts of boron. Boracic acid and borax were previously used for the curing of meat but this is no longer admissable because of the health hazard.
Experiments revealed that intestinal streptococci serve as more reliable indicators of faecal contamination of biltong than coli-bacilli because they are better able to withstand dehydration and salting. In addition it was observed that the organisms responsible for food poisoning did not die out readily in either contaminated meat or wet or dry biltong. On the other hand the cysticercus stage of the tapeworm of man [Taenia saginata] failed to survive in properly cured biltong. The use of galvanized containers for the pickling process, particularly when vinegar is used, may lead to the presence of zinc in the biltong which may be responsible for chronic poisoning.
Meticulous attention to all aspects of good meat hygiene as well as production methods is essential to ensure that biltong has no health hazards. Salting and dessication cannot be relied upon to replace good meat hygiene.
During the year all plants producing bone, blood, carcase or fish meal were inspected prior to registration or the annual registration under Fertiligers, farm Feeds, Seeds and Remedies Act [Act 36 of 1947].
9. STOCK INSPECTION SERVICES
For the third year in succession stock inspection services were seriously disrupted by the essential seconding of a large proportion of the inspectorate staff to campaign duties – Foot and Mouth Disease in the Eastern Transvaal
and Swaziland, Newcastle Disease in the Eastern Cape and Sheep Scab in various parts of the Republic.
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The absence of so many officials from their normal spheres of duty for periods varying up to 6 months and more, left only skeleton staffs to cope with routine work and all other eventualities, in those areas not directly affected by the epizootics.
The indispensability of the inspectorate branch of the Division to the welfare of the stock industry of the Republic, and its adoptability and flexibility, is once again stressed by the fact that the Division was able to conduct successful eradication campaigns against serious epizootics and at the same time satisfactorily maintain essential services in the rest of the country.
In view of the essentiality of efficient stock inspection services, the increasing number of vacancies caused by retirements and resignations is viewed with alarm, especially taking into account the small number of recruits drawn to the service by the existing salaries.
10. ANIMAL HEALTH EXTENSION SERVICE
In our rapidly expanding economy, where the supply of products of animal origin is in danger of being outstripped by the demand, only the soundest stock farming practices are admissable. The Division is aware that a regrettably high percentage of farmers do not utilize the mass of scientific knowledge available, and every effort is made to remedy this defect.
During the year contributions were made to the “Calling All Farmers” radio programmes; articles were writeen for the rural press and national agricultural journals as well as Departmental publications; lectures covering a wide spectrum of veterinary interest, usually accompanied by short lectures, were presented; farmer’s study groups were assisted by means of lectures and discussions; pamphlets were drawn up for distribution to farmers, either directly or indirectly through inspectorate personnel; by means of personal interviews State Veterinarians did valuable and very effective extension work.
11. IMPORT AND EXPORT CONTROL
[1] IMPORT
Wet salted hides 117 116 units Karakul pelts 2 963 units Bone meal 387 000 kg Blood meal 21 770 kg Carcase meal 111 120 kg Hooves 44 020 kg Bristles 80 645 kg 1 043 bales
Wool 3 701 084 kg Mohair 10 059 kg
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Ostrich feathers 34 kg Feathers 3 kg Rabbitfur 4 187 kg Tallow 84 552 kg Casein 332 361 kg Pancreatic glands 41 309 kg Semen 238 ampoules Fish eggs 120 000 units Processed skins and trophies 165 units Mineral stock feed 6 637 bags Groundnut hay 45 360 kg Cat food 3 363 kg Fish food 71 kg Fertiliser 320 000 bags Second hand bags 1 038 bales Blood specimens 40 units Veterinary drugs 313 cartons
[2] EXPORT
For purposes of export, veterinary examination and certification in accordance with the requirements of importing countries were undertaken in respect of the following animals:
Cattle 6 589 Sheep 19 960 Goats 722 Pigs 11 372 Equines 1 021 Dogs 1 398 Cats 159 Birds 2 715 Poultry 571 029 Wild animals 297 Other animals 54
The products listed below were certified for export:-
Biltong 1 kg Frozen and chilled meat 13 696 873 kg Canned meat 1 534 040 kg Poultry meat 26 932 kg Bacon 1 640 620 kg Whale meat 13 649 cases
Whale meat extract 33 475 bags
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Sausage casings 59 011 kg Hides and Skins 15 811 433 kg 76 902 bales 100 994 units Karakul pigs 836 695 units Chincilla pelts 147 kg Horns and Hooves 262 071 kg Fish meal 129 915 kg Molasses meal 16 115 bags Whale protein meal 105 071 bags Citrus meal 414 545 kg Hairs and Bristles 34 115 kg Wool 61 645 860 kg Mohair 4 767 651 kg Ostrich feathers 23 041 kg Feathers 30 435 kg Ox gall 3 035 kg Egg powder 477 100 kg Poultry feed 87 060 bags Processed skins and trophies 6 813 units Game skins 7 385 kg Elephant skin 22 626 kg Elephant ears 83 kg Ivory 10 623 kg Lamb paunches 5 173 units Grains 112 728 t Potatoes 1 794 955 kg Onions 129 580 kg Grapes 18 267 349 kg
12. TRAINING
[1] VETERINARIANS
The training of Veterinarians was continued in 1970, not only to comply with the requirements for prevention and control of animal diseases in South Africa, but also to supply basic training for research and professional services in related fields.
Forty-five students were again admitted to te second academic year of the Faculty of Veterinary Science of the University of Pretoria. During the year, however, a commission, appointed by the Minister of Agriculture, investigated the training requirements for veterinary surgeons. The Government has
accepted the recommendation that ninety students should be admitted annually. On account of this decision, the Faculty members are planning the
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extension of their facilities and buildings to accommodate 90 students in the second year.
At present the Faculty is still connected to the Department of Agricultural- Technical Services. During the year a previously appointed commission continued its inquiry to determine whether or not the above situation should be maintained.
During the past two months additions to the Department of Medicine and to the students residence have been completed, with the result that the original building programme, which was to provide accommodation for groups of forty- five students, has been completed.
The activities of the Faculty have followed the usual pattern. There is, however, concern because no applications were received for certain full-time teaching posts which were advertised under the previous salary scale. Even after the new salary scales had been circulated, only slight interest was shown in some of these posts, in others none.
At present student numbers are as follows:-
B.V.Sc. II = 46 B.V.Sc. III = 41 B.V.Sc. IV = 49 B.V.Sc. V = 40 B.V.Sc. V1/2 = 6
Postgraduate students registered in 1970:
D.V.V.G. = 1 M. Med. Vet. = 24 D.V.Sc. = 7
Degrees awarded [Sept. 1969 and March 1970]:
B.V.Sc. = 35 D.V.V.G. = 1 M.Med.Vet. = 0 D.V.Sc. = 2
[2] OTHER VETERINARY TRAINING
As in the post, State veterinarians were responsible for the teaching of veterinary subjects for the Diploma course at the various Agricultural College, including the Bantu Agricultural College at Fort Hare.
At Fort Cox, the State Veterinarian East London conducted the veterinary course for Bantu Assistant Stock Inspectors. 53/…
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As a result of the secondment of so many members of the inspectorate staff to campaign duties, in – service training – both formal and informal – could not receive the desired attention.
After many set-backs and interruptions, the compilation of the manuals for all ranks of the inspectorate personnel has nearly reached completion, and only minor details have to be finalised before the manuals can be taken into use.
13. STOCK CENSUS
SHEEP
REGION CATTLE WOOLED NON- GOATS HORSES DONKEYS PIGS FOWLS DOGS CHINCHILLAS WOOLED AND MULES
Cape East & Karoo 882 847 10 356 905 1 153 343 1 533 343 42 707 18 175 94 340 1 823 730 87 929 11 445 Eastern Transvaal 1 011 002 51 794 347 903 806 430 2 493 37 231 80 402 670 713 58 674 565 Highveld 2 539 148 5 404 493 634 081 255 427 106 660 17 452 254 935 2 801 225 12 933 1 332 Natal 2 583 444 1 617 426 276 656 815 173 51 829 53 774 134 431 3 353 301 214 363 3 707 O.F.S 1 283 411 3 795 186 4 236 097 795 041 64 016 38 964 74 305 730 659 68 980 1 872 Transvaal 2 118 066 2 391 142 424 793 429 227 27 141 19 322 225 882 10 129 860 186 110 42 110 Winter Rainfall 315 010 3 674 000 1 054 000 511 000 29 400 15 200 130 600 4 929 000 113 450 4 020
TOTAL 10 732 928 27 290 946 8 126 873 5 146 119 324 246 200 118 994 895 24 438 488 742 439 65 051
Please refer to next page for analysis of cattle figures.
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DISTRIBUTION OF CATTLE
WHITE OWNERS NON-WHITE OWNERS REGION WHITE NON-WHITE WHITE AREAS NON-WHITE AREAR AREAS AREAS Cape East & Karoo 702 609 11 361 40 243 128 634 Eastern Transvaal 437 211 50 52 158 521 583 Highveld 2 225 605 62 197 273 116 208 Natal 1 048 566 1 906 279 293 1 253 679 O.F.S. 1 154 792 1 070 6 000 121 549 Transvaal 1 694 030 6 451 208 288 209 297 Winter Rainfall 309 800 960 3 900 350
Total 7 570 613 21 860 787 155 2 351 300
14. PUBLICATIONS
[1] DIVISION OF VETERINARY SERVICES
[a] IN SCIENTIFIC JOURNALS
1. DE VOS, V. 1969
Pseudo-pregnancy in the black-backed jackal [Canis mesomelas Schreber]. J.S. Afr. Vet. Med. Ass. 40[4], 381-383.
2. DE VOS, V. & VAN NIEKERK, C.A.W.J. 1969
Brucellosis in the Kruger National Park. J.S. Afr. Vet. med. Ass. 40[3], 331-334.
3. MANSVELT, P.R. 1969
The zoo-sanitary position and animal disease control methods in the Republic of South Arica. Bull. Off. Int. Epiz. 72[1], 1055-1058
4. MASTERS, P.M.S. 1969
Poultry diseases as they affect the condemnation of carcasses for human consumption. Public Health 69[12], 539-541.
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5. WILKINS, C.A. 1969
Verkoeling van vleis. Public Health 69[a], 395-399
6. WILKINS, C A. 1970
A note on the results of a survey of the concentration of insecticides in cattle dips in the Natal Midlands. J.S. Afr. vet. med. Ass. 41[1], 53.
7. YOUNG, E. 1969
The significance of infectious diseases in African game populations. Zoologica Africana 4, 275.
8. YOUNG, E. 1970
The diagnosis and control of game diseases. Zoologica Africana 5, 167.
9. YOUNG, E, WAGENER, L.J.J. & BRONKHORST, P J L 1969
The blue wildebeest as a source of food and by-products. J.S. Afr. vet. med. Ass. 40[3], 315-318.
10. ZUMPT, I.F. 1969
Factors influencing rabies outbreaks: The age and breeding cycle of the yellow mongoose, Cynictis penicillate [G. Cuvier]. J.S. Afr. vet. med. Ass. 40[3], 319-322.
11. ZUMPT, I.F. 1970
The ground squirrel. Afr. Wild Life 24[2], 115-121.
[b] IN DEPARTMENTAL PUBLICATIONS
1. VAN TONDER, E.M. 1969
Infections of the genital organs in rams. Farming in S.A. Sept. 1969.
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[2] VETERINARY RESEARCH INSTITUTE, ONDERSTEPOORT
[a] IN SCIENTIFIC JOURNALS
1. BASSON, P.A., ZUMPT, F., 1969
Oestrus dubitatus n. sp. From the nasal cavities of the blue wildebeest [Connochaetes taurinus Burchell, 1823] in the Esotsha National Park, South West Africa, Madoqua, Madoqua, 1, 57-60.
2. BASSON, P.A., MORGENTHAL, J.C., BILBROUGH, R.B., MARAIS, J.L., KRUGER, S.P., VAN DER MERWE, J.L. de B., 1969.
Grootlamsiekte, a specific syndrome of prolonged gestation in sheep caused by a shrub, Salsola tuberculata [Fenzl ex Moq.] Schinz var. tomentosa C.A. Smith ex Aellen. Onderstepoort J. vet. Res., 36, 59-104.
3. BASSON, P.A., PIENAAR, J.G. & VAN DER WESTHUIZEN, B., 1970.
The pathology of ephermeral fever: a study of the experimental disease in cattle. Jl S. Afr. vet. med. Ass., 40, 385-397.
4. BOUQUET, Y. & OSTERHOFF, D.R.,1968.
Relationships of some blood polymorphic systems with physiological traits in animals. Proc. Intern. Coll. Trop. Anaem. Antwerpen, 189-200.
5. BOYAZOGLU, P.A. & BARRETT, E.L., 1969.
Lysine, methionine, choline supplementation effects in growing – finishing pigs. Proc. S. Afr. Soc. Anim. Prod., 8, 99-100.
6. BUYS, S.B., 1970
Die isolasie van Haemophilus gallinarum. Jl S. Afr. vet. med. Ass., 41, 55-58.
7. CAMERON, C.M. & FULS, W.J.P., 1970
Two new Salmonella serotypes: 13, 22: Z 29: 1,5 [7] and 56: D Jl S. Afr. vet. med. Ass. 41, 15.
8. COETZEE, L., 1969
Observations on the importance, diagnosis and control of avian mycoplasmosis in South Africa. O.I.E. Bull. 1969 57/…
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9. DU PLESSIS, J.L., DUPOUEY, P., LATASTE-DORDLE, C. & FAURE, M., 1969.
Structure antigénique des leptospires, comparaison des resultats donnés par plusieurs methodes immunologiques. Ann Inst. Pasteur, 118, 179-190
10. DU PLESSIS, J.L., PIENAAR, J.G. & BASSON, P.A., 1970
Detection of antibodies against Strongyloides papillosus by the indirect immuno-fluorescent method. Jl S. Afr. vet. med. Ass., 40, 399-404.
11. GERNEKE, W.H., 1969.
Sterility in a bull, co-twin to a freemartin. Jl S. Afr. vet. med. Ass., 40, 279- 283.
12. HOWELL, C.J., 1970.
Entomologiese berigte:
1. Leptoconops. 2. Brommerweerstand. Jl S. Afr. vet. med. Ass. 41, 71-74.
13. KLEEBERG, H.H., 1968.
La guimioterapia comounanuera forma de lucha contra la Tuberculosis Bovina según el, Veterinaria y zootecnia, 20, 10-12.
14. KLEEBERG, H.H. & NEL, ELLEN E., 1969.
Porcine mycobacterial lymphadenitis. Jl S. Afr. vet. med. Ass., 40, 233-250.
15. KOCK, S.G. & KISTNER, A., 1969.
Extent of solubilisation of – cellulose and hemicellulose of low-protein teff hay by pure cultures of cellulolytic rumen bacteria. J. gen. Microbiol., 55, 459-462
16. KRUGER, S.P., COLLINS, MARIE H., VAN NIEKERK, J.W., McCULLY, R.M. & BASSON, P.A., 1969.
Experimental observations on the South African strain of Trichinella spiralis. Proceedings of the second international conference on trichinellosis Wroclaw, Wiadomósci Parazytologiczne, 25, 546-554.
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17. LACATSAS, G., 1969.
The structure of bovine ephemeral fever virus. Jl S. Afr. vet. med. Ass., 40, 230.
18. LAGATSAS, G., THEODORIDIS, A. & ERASMUS, B.J., 1969.
Electron microscope studies on bovine ephemeral fever virus. Arch. ges. Virusforsch. 28, 390-398
19. LOVEDAY, R.K., 1969.
Porcine mycobacterial lymphadenitis: Some epidemiological aspects. Jl S. Afr. vet. med. Ass., 40, 253-256.
20. McCONNEL, E.E., VAN RENSBURG, I.B.J. & VAN WYK, G.A., 1970
A case of adenocarcinoma of the olfactory mucosa in sheep of possible infectious origin. Jl S. Afr. vet. med. Ass., 41, 9-15.
21. McCULLY, R.M. BASSON, P.A., PIENAAR, J.G., ERASMUS, B., YOUNG, E., PIETERSE, L.M., 1969.
Herpes nodules in elephants. Jl S. Afr. vet. med. Ass., 40, 422.
22. McCULLY, R.M., KRUGER, S.P., BASSON, P.A., EBEDES, H. & VAN NIEKERK, J.W., 1969.
Strongylidosis: Delafondiasis in the zebra. Onderstepoort J. vet. Res., 36, 105-128.
23. NEETHLING, L.P., BROWN, J.M., OSTERHOFF, D.R., DE WET, P.J. WARD- COX, I.S., 1969.
The functional advantage of haemoglobin type A in haemolytic syndromes in sheep, phenylhydrazine, organic selenium and partial exsanguination as external agents in the production of anaemias. Jl S. Afr. vet. med. Ass., 40, 121-126.
24. NEITZ, W.O., 1969.
Observations on the duration of premunity following administration of the bivalent redwater vaccine. Jl S. Afr. vet. med. Ass., 40, 419 420.
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25. OELLERMANN, R.A. & MILLER, ELSA M., 1969
The influence of conditioned media and non-essential amino acid supplementation on the growth of cells in vitro. J. Cell. Physiol., 74, 299-306.
26. OELLERMANN, R.A., ELS, H.J. & ERASMUS, B.J., 1970.
Characterization of African Horsesickness virus. Arch. Ges. Virusforsch., 29, 163-174
27. OSTERHOFF, D.R., 1968.
Routine bovine blood grouping in the Republic of South Africa. Milk Recording Res. Results, 11, 1-13.
28. OSTERHOFF, D.R., 1970.
Blutgruppenbestimmung beim Rind auch in Entwicklungsländern? Landwirt im Ausland, 4, 45-47.
29. OSTERHOFF, D.R. & KEEP, M.E., 1970.
Natural variation in the blood proteins of white and black rhino. The Lammergeyer, 11, 50.
30. OSTERHOFF, D.R., YOUNG, E. & WARD COX, I.S., 1970.
A study of genetic variants in African buffalo. Jl S. Afr. vet. med. Ass., 41, 33-37.
31. PROCOS, J., 1969.
Ovine hypoglycaemic ketosis. S. Afr. med. J., 43, 1326
32. ROSS, R., MUNOZ, J. & CAMERON, C., 1969.
Histamine-sensitizing factor, mouse protective antigens, and other antigens of some members of the genus Bordetella. J. Bact., 99, 57-64.
33. SHANE, BARBARA S., GOUWS, L. & KISTNER, A., 1969.
Cellulolytic bacteria occurring in the rumen of sheep conditioned to low- protein teff hay. J. gen. Micbrobiol., 55, 445-457.
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34. STEYN, D.G., 1969.
The response of the bovine adrenal cortex to Halothane anaesthesia. Jl S. Afr. med. Vet. Ass., 40, 353-364.
35. STEYN, D.G., 1969
The blood supply to the periosteum of the canine femur. Jl S. Afr. med. Vet. Ass., 40 371-374.
36. SWEATMAN, G.K., WALKER, JANE B. & BINDERNAGEL, J.A., 1969.
Stages in the development of Choriopsoroptes kenyensis gen. Et sp. N. [Acari: Sarcoptiformes: Psoroptidae], a body mange mite from captive African Buffalo, Syncerus caffer, in Kenya. J. Parasit., 55, 1298 – 1310
37. VAN DER WALT, K. & OSTERHOFF, D.R., 1969.
Blood transfusion in cattle with special reference to the influence of blood groups. I. Single transfusions into young animals and pregnant cows. Jl S. Afr. vet. med. Ass., 40, 107-117.
38. VAN DER WALT, K. & OSTERHOFF, D.R., 1969.
Blood transfusion in cattle with special reference to the influence of blood groups. II. Repeated blood transfusions. Jl S. Afr. vet. med. Ass., 40, 265- 275.
39. VAN GYLSWYK, N.O., 1970.
The effect of supplementing a low-protein hay on the cellulolytic bacteria in the rumen of sheep and on the digestibility of cellulose and hemicellulose. J. Agric. Sci. Camb., 74, 169-180.
40. VAN GYLSWYK, NO.O., 1970.
A comparison of two techniques for counting cellulolytic rumen bacteria. J. gen. Microbiol., 60, 191-197.
41. VAN GYLSWYK, N.O. & HOFFMAN, J.P.L., 1970.
Characteristics of cellulolytic cillobacteria from the rumens of sheep fed teff [Eragrostus tef] hay diets. J. gen. Microbiol., 60, 381-386
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42. VAN RENSBURG, I.B.J., ROOS, C.J. & McCONNELL, E.E., 1970.
Diverticulosis in a cow. Jl S. Afr. vet. med. Ass., 41, 76.
43. VERWOERD, D.W. & HUISMANS, H., 1969.
On the relationship between bluetongue, African horsesickness and reoviruses: hybridization studies. Onderstepoort J. vet. Res., 36, 185-190.
44. VERWOERD, D.W., LOUW, H. & OELLERMANN, R.A., 1970.
Characterization of bluetongue virus ribonucleic acid. J. Virol., 5, 1-7
[b] IN POPULAR JOURNALS
1. GERNEKE, W.H., 1969.
Kliere en afskeiding. Spectrum, 7, 196-200.
2. KLEEBERG, H.H., 1970.
Moderne riglyne in die chemoterapie van tuberkulose. SANTA Nuus, Deel 9, Nr. 3
3. OSTERHOFF, D.R., 1970.
The correlation between milk and beef production in dairy cattle with particular reference to the Friesland breed. S.A. Friesland Journal, 47, 71-73.
4. ROOS, C.J., 1969.
Intercontinental Fliers. S.A. Digest, July 4th, 1969, 15.
5. SUTTON, G.D., 1969.
The use of Onderstepoort vaccines for sheep. Wolboer, July 1969.
6. SUTTON, G.D., 1970.
Onderstepoort Veterinary Research Laboratory. Wolboer, May 1970.
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7. VAN DEN HEEVER, L.W. & GIESECKE, W.H., 1970.
The necessity for, and methods of, mastitis control. S.A. Friesland Journal, 47, 60-66.
15. LEGISLATION
During the report year the following Government Notices were published under the Acts indicated:
[a] ANIMAL DISEASES AND PARASITES ACT [ACT 13 OF 1956]
1. G.N. No. 3209 of 29.5.69 to prevent the introduction, occurrence or spread of Newcastle Disease by controlling the movements of poultry and poultry products in the magisterial district of Port Elizabeth and portion of the magisterial district of Uitenhage.
2. G.N. No. 3227 of 5.9.69 to subsitute for the regulations published under G.N. No. 1632 of 31.7.53, new regulations controlling the movement of certain stock form specified abattoirs.
3. G.N. No. 3473 of 9.10.69 to further amend G.N. No. 475 of 24.3.61 by adding the magisterial districts of Alexandria, Kirkwood, Port Elizabeth and George to the list of districts to which compulsory anthrax inoculation of cattle, equines, sheep and goats applied.
4. G.N. No. 887 of 28.11.69 to declare a portion of the Veterinary Research Institute, Onderstepoort a quarantine station for imported rabbits.
[b] ANIMAL SLAUGHTER, MEAT AND ANIMAL PRODUCTS HYGIENE ACT [ACT 87 OF 1967]
1. G.N. No. R3455 of 3.10.69 to exampt from certain provisions of Act 87 of 1967 all abattoirs except the 17 largest in the Republic.
2. G.N. No. R3456 of 3.10.69 to exempt from the provisions of Act 87 of 1967 animals slaughtered by owners of land for private purposes.
3. G.N. No. R3464 of 3.10.69 to provide for the grading of abattoirs.
4. G.N. No. R266 of 3.10.69 to proclaim the coming into operation on the same date of all sections except sections 16 and 17 of Act 87 of 1967.
5. G.N. No. R3505 of 9.10.69 to promulgate the Standing Regulations under Act 87 of 1967. 63/…
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6. G.N. No. R12 of 2.1.70 to exclude the Game Abattoir of Skukuza from the provisions of sections 17 and 26[1] of Act 87 of 1967.
7. G.N. No. R13 of 2.1.70 to declare elephants, buffalo, zebras, blue wildebeest and impala animals for the purposes of Act 87 of 1967.
8. G.N. No. R14 of 2.1.70 to exclude the species listed in G.N. No. R13 of 2.1.70 as animals under the Act, in all areas except the Kruger National Park.
[c] THE LIVESTOCK BRANDS ACT [ACT 87 OF 1962]
1. G.N. No. R3743 of 14.11.69 to amend the regulations published in G.N. No. R519 of 29.3.68.
2. G.N. No. R3744 of 14.11.69 to exclude pure bred livestock from the proviso’s of section 18[2] of the Act.
16. TECHNICAL RELATIONS WITH OTHER COUNTRIES
[1] LIAISON AND CO-OPERATION WITH AFRICAN TERRITORIES
An indication was given earlier of the co-operation with and assistance to Swaziland in the campaign to eradicate Foot and Mouth Disease in that country. Just after the outbreak Drs. P.R. Mansveld and A. van Heerden visited Swaziland from 21 to 23.10.69 to discuss the assistance needed, and again on 8 and 9.2.70 to arrange for the withdrawal of South African officials. Drs. T.A.T. Louw and J.M. Erasmus were consecutively in command of the South African contingent in Swaziland from the beginning of the operation until 24.12.69.
During the period 7.-11.9.69 Drs. J.P. van der Merwe and J. Meeser attended the meeting of the Interterritorial Foot and Mouth Disease Commission in Lourenco Marques.
A meeting in connection with international movements of animals and animal products and Foot and Mouth Disease control, held in Swaziland on 19 and 20.3.70 was attended by Drs. M.C. Lambrechts, P.R. Mansveld, J. Meeser and D.E. Truter.
Under “Trypanosomiasis” details were supplied of the combined Rhodesia – Angola – Mocambique – South Africa operations in tsetse fly eradication
campaigns. In connection with these, Dr. E.B. Kluge visited the spraying areas in the Eastern and Western Caprivi and Angola during the period 21.7.69 – 12.8.69, and the areas in Rhodesia and Mocambique between 26.8.69 and 1.9.69. During the two periods 21.9.69 – 25.9.69 and 28.9.69 – 7.10.69 Dr Kluge visited Rhodesia and Mocambique and the Eastern and Western Caprivi and Angola respectively in connection with end-of-campaign duties. 64/…
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Drs. B.C. Jansen, M.C. Lambrechts and E.B. Kluge met Dr. J.P. van der Merwe [S.W.A.] and representatives of Angola and Botswana at Serpa Pinto, Angola, between 10 and 12.2.70 to finalize plans for the 1970 spraying operations. During the period 22-25.3.70 Drs. Lambrechts and Kluge held discussions with representatives of Rhodesia and Mocambique at Lourenco Marques.
Dr. Kluge visited Rhodesia and Mocambique between 23 and 29.6.70 to start off the 1970 tsetse eradication campaign.
On 22 and 23.9.69 Drs. Lambrechts and Mansveld attended a meeting of the Nature and Game Conservation Commission of SARCCUS in Pretoria.
Amongst the visitors to the Research Institute, numbered 6 from S.W.A., 4 from Botswana, 2 from Swaziland and one each from Kenya, Lesotho, Mocambique and Rhodesia.
Quantities of vaccines supplied by Onderstepoort to countries on the African continent are summarized below:-
Angola 160 doses Horsesickness vaccine Botswana 314 970 doses 20 vaccines Congo [Kinshasa] 5 500 doses C.A. & Gallsickness Lesotho 170 446 doses 7 vaccines Malawi 1 248 303 doses 6 vaccines Mocambique 23 007 doses 3 vaccines Rhodesia 3 020 598 doses 17 vaccines Swaziland 6 743 doses 11 vaccines S.W.A. 196 124 doses 15 vaccines Zambia 1 807 190 doses 9 vaccines
In addition, 93 950 units of bovine, 90 320 of avian and 20 000 of human tuberculin, 2 040 ml of B.W.D., 140 ml of P.P.L.O and 432 ml of Brucella antigen were supplied to African countries.
[2] LIAISON WITH OVERSEAS COUNTRIES
[a] SCIENTIFIC VISITORS
During the year 103 scientists from 11 overseas countries were received at Onderstepoort. These visits varied in length from days to months. Maj, Ernest E. McConnel of the U.S.A.F. was seconded to the Veterinary Research Institute on 19.6.70.
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[b] TECHNICAL ASSISTANCE AND ADVICE
The following vaccines and laboratory products were supplied to the countries indicated:
China 200 doses Anthrax vaccine. Israel 25 000 bluetongue vaccine. 2 200 doses Lambsiekte vaccine. New Zealand 2 500 doses Anthrax vaccine. Persian Gulf 440 doses Horsesickness vaccine. Peru 3 000 units Tuberculin [Avian] 3 000 units Tuberculin [Bovine].
It may be pointed out that during the year a total of 7 035 613 doses of vaccine and other biologicals were issued to foreign countries, including those on the African continent.
[c] INTERNATIONAL ORGANISATIONS
The Annual Congress of the O.I.E. in Paris – 23 to 30 May 1970 – was attended by Dr. J.P. van der Merwe, Deputy Chieef, Division of Veterinary Services.
[d] STUDY TOURS AND OFFICIAL VISITS
In addition to the visits referred to under “Liaison and Co-operation with African Territories,” mention must also be made of the following:-
1. Dr. J.P. van der Merwe – London. Liaison with British Veterinary Field Organisation, 30 May – 7 June 1970.
2. Dr. B.J. Erasmus – Visit to France, Germany and England to attend the 2nd International Conference for Infectious Diseases of Equines, the information and consultation meeting of delegates of the veterinary services of member countries of the O.I.E. and the Conference on the Biology of “Large RNA Viruses”, as well as to carry out a study tour, 13.6.69 – 28.7.69.
3. Dr. H.H. Kleeberg – Visit to Germany, U.S.A., Peru, Bolivia, Argentine and Brazil to attend conferences, and lecture on Tuberculosis on invitation, 19.8.69 – 7.10.69.
4. Dr. B.J.H. Barnard – Parkville, Australia – Study tour on Bovine Pleuropneumonia and Vibriosis, 30.6.69 – 3.8.69.
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5. Dr. P.A. Boyazoglu – Germany, United Kingdom and U.S.A. To study the automatic amino acid analyser and visit research institutes and breeding establishments overseas, 12.4.70 – 21.5.70.
6. Dr. K.E. Weiss – Visit to Spain, Portugal, France, Holland, Belgium, Germany and Italy on a technical mission to improve agricultural relations with foreign countries.