Clinical communication — Kliniese mededeling

Gousiekte in African buffalo (Syncerus caffer)

J A Lawrencea*, C M Fogginb and L Prozeskya

sections from the 3 animals were exam- ABSTRACT ined by all 3 authors. Three African buffalo (Syncerus caffer) that died after capture and translocation from Mutirikwe Recreational Park in southern Zimbabwe showed macroscopic and microscopic Pathology lesions of cardiomyopathy compatible with a diagnosis of gousiekte. The buffalo had had Case A access to , a that is known to cause gousiekte. Death was This animal was a 2-tooth heifer, 2–3 attributed to cardiac failure as a result of previous consumption of the plant, exacerbated by years old, in very good condition. The the stress of translocation. lungs were severely congested and oede- Keywords: African buffalo, cardiomyopathy, gousiekte, Mutirikwe Recreational Park, matous, with froth mixed with rumen Zimbabwe, Pavetta schumanniana, Syncerus caffer. contents in the trachea and bronchi. The Lawrence J A, FogginCMF,Prozesky L Gousiekte in African buffalo (Syncerus caffer). liver was slightly swollen and congested, Journal of the South African Veterinary Association (2010) 81(3): 170–171 (En.). Pathology the kidneys were slightly swollen and Section, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of pale, the spleen was swollen with promi- Pretoria, Private Bag X04, Onderstepoort, 0110 South Africa. nent lymphoid follicles. There were approximately 500 m of slightly turbid, brownish fluid in the abdominal cavity. INTRODUCTION the lake. The Park is heavily stocked with The myocardium was pale, with the cut Three African buffalo (Syncerus caffer) more than 25 species of wild mammals, surface slightly mottled and there were that died after capture and translocation including 3 large grazing species, namely 50 m of clear, yellow fluid containing showed macroscopic and microscopic African buffalo, white rhinoceros (Cerato- fibrin clots in the pericardial sac. The lesions of cardiomyopathy. The common- therium simum) and hippopotamus (Hip- mucosa of the small intestine was very est cause of cardiomyopathy in free- popotamus amphibius). The buffalo were congested and haemorrhagic. There was ranging ruminants in southern Africa is introduced as a foot-and-mouth disease- superficial bruising of the lower limbs, gousiekte, a sub-acute to chronic intoxica- free breeding herd in the late 1970s. The tearing of the fascia in the right axilla and tion by members of the plant vegetation in the park is predominantly prominent gelatinous oedema of the that contain the polyamine miombo woodland (Brachystegia spicifor- neck, especially adjacent to the trachea, pavetamine4. The previous assumption mis and Julbernadia globiflora), with thick- probably resulting from trauma during that the myocardial lesions described in ets dominated by Peltophorum africanum, capture and transportation. The superficial the literature are pathognomonic has Terminalia sericea, Combretum spp. and lymph nodes were moderately swollen. been discarded5, but a diagnosis of Acacia karoo, small patches of evergreen Microscopic examination of the myo- gousiekte is justified in cases of cardio- riverine species and areas of middle veld cardium revealed marked variation in the myopathy where one of the grassland. A barren zone along the lake width of the myofibres, indicating both known to cause the condition is present. shore, which is subject to periodic flood- hypertrophy and atrophy. The myofibre This paper describes an outbreak in ing, supports only a sparse cover of an- nuclei were hypertrophic and sometimes Mutirikwe Recreational Park in Zimba- nual herbs and grasses. arranged in chains. There were numerous bwe and considers possible epidemiologi- small foci in which the myofibres had cal factors responsible for the outbreak. CASE HISTORIES disintegrated and been replaced by Twenty-seven buffalo were captured on fibrosis of varying degrees of maturity. MUTIRIKWE RECREATIONAL PARK 31 May 2007 in the Park and loaded in Oedema spaces and lymphocyte/macro- Mutirikwe (Kyle) Recreational Park in trucks for translocation to Mazowe, north phage infiltration were variably present southern Zimbabwe (20°10’S, 31°01’E) of Harare. Two died in the truck the 1st between fibres. Significant features in includes a wildlife area of approximately night before they were transported. Post other organs were marked pulmonary 3800 ha enclosed by Lake Mutirikwe and mortem examination of 1 revealed sub- congestion and protein-rich oedema, a game-proof fence. In the north of the acute suppurative pericarditis and pleu- marked hepatic congestion, congestion of Park the Beza Range rises to a height of risy of undetermined aetiology; the other the small intestine mucosa and protein in 1485 m. Between this range and Lake was not examined. The remaining 25 the glomeruli and tubules of the kidney. Mutirikwe is an undulating plain averag- were unloaded at Mazowe on 2 June; Case B ing 1070 m above sea level. The plain 3 from a single truck died over the next Putrefaction in the myocardium was terminates in an area of broken hills in the 2 days. Post mortem examinations were advanced. There was no evidence of south of the Park between the 2 arms of performed by a layman on 2 cows (Cases disintegration of myofibres or fibrosis, but aPathology Section, Department of Paraclinical Sciences, B and C), and specimens in formalin were Faculty of Veterinary Science, University of Pretoria, hypertrophy and atrophy of adjacent submitted to the Wildlife Unit of the Private Bag X04, Onderstepoort, 0110 South Africa. fibres were present in some areas. bWildlife Unit, Department of Veterinary Services, Private Department of Veterinary Services in Bag BW6238, Borrowdale, Harare, Zimbabwe. Harare. The last animal to die, a heifer Case C *Author for correspondence. E-mail: [email protected] (Case A), was examined post mortem by Microscopic myocardial lesions were Received: February 2010. Accepted: May 2010. one of the authors (CMF). Histological similar to those in Case A.

170 0038-2809 Tydskr.S.Afr.vet.Ver. (2010) 81(3): 170–171 In all 3 animals there was evidence of The unusual feature is the occurrence of escape unauthorised hunting, which was mild degeneration in skeletal muscle plant toxicosis in free-living wildlife in a suspected to be occurring in the Park at affecting less than5%offibres, character- location in which they had lived for several the time. For whatever reason, it appears ised by variation in width, loss of striation generations. It is generally assumed likely that the buffalo were forced into a and occasional fragmentation of sarco- that animals in such situations become habitat with which they were not familiar plasm, with a light interstitial macro- adapted to their environment and either and ate the plant because they failed to phage infiltration. These lesions were learn to avoid or develop the ability to recognise it and because of shortage of attributed to the effects of capture and degrade or detoxicate potentially lethal other, more familiar, food. The reason for transport but were not considered clini- toxic plants3. For example, plant toxicosis the fatalities being confined to animals in cally significant. does not feature as a cause of mass the same truck is also unclear. The herd die-offs in large mammals in a 1994 bull was in that truck, and he may have Diagnosis review6. Nevertheless, plant poisoning caused more disturbance during trans- The pathological changes in the animals may occur in situations of shortage of port than the animals in the other trucks. that died were those of cardiomyopathy food, which make avoidance difficult and There is no way of knowing whether in the early stages in Case B and more reduce the capacity for degradation and gousiekte had occurred previously on a 3 advanced in Cases A and C. The history of detoxication . smaller scale in buffalo in the park, or in sudden death after being subjected to Gousiekte in wildlife has been reported any other species, or what proportion of the stress of capture and transport were on only 1 previous occasion1. On that occa- the animals that survived this incident characteristic of gousiekte in domestic sion springbok (Antidorcas marsupialis) had subclinical lesions from which they ruminants. Of the plants known to cause were confined to overgrazed camps in recovered. Veterinarians and wildlife gousiekte, Pavetta schumanniana occurs which there was very little vegetation. management specialists need, however, widely in the area. The plant is a slender When the gousiekte plant, Pachystigma to be aware of the possible occurrence of shrub or small tree that has a preferred pygmaeum, sprang up after the first rains, this disease in animals under their care in habitat in woodland in association with the animals ate it for want of any other situations where grazing is scarce. granite koppies and outcrops2, such as oc- green feed and succumbed (T W Naudé, curs in parts of the Park that were fre- University of Pretoria, pers. comm. 2009). REFERENCES quented by the buffalo. The plant is No such obvious precipitating factor 1. Basson P A 1987 Poisoning of wildlife in known to be browsed by cattle on occa- was present in the outbreak described in southern Africa. Journal of the South African sion. this paper, and the following explanation Veterinary Association 58: 219–228 for the outbreak is speculative. The 2. Coates Palgrave K 2002 Trees of Southern Africa (3rd edn) (Revised by Coates Palgrave DISCUSSION capture operative observed that, rather M). Struik Publishers, Cape Town The combination of death from cardiac than frequenting the less wooded areas of 3. Fowler, M E 1983 Plant poisoning in free- failure after stress, lesions of subacute the Park as in previous years, the buffalo living wild animals: a review. Journal of cardiomyopathy and the presence of a spent most of their time in 2007 in the Wildlife Diseases 19: 34–43 known toxic plant in the area where the densely wooded areas amongst the 4. Kellerman T S, Coetzer J A W, Naude T W, Botha C J 2005 Plant poisonings and myco- buffalo grazed is sufficient evidence for a granite outcrops, which is where the toxic toxicoses of livestock in southern Africa (2nd diagnosis of gousiekte. Cases A and C plant is most common (C van der Riet, edn). Oxford University Press, Cape Town were ‘typical’ of the disease, while Case B Harare, pers. comm. 2009). Possible rea- 5. Prozesky L 2008 A study of the pathology was ‘atypical’5. Degenerative changes in sons for this are 2-fold. One is the compe- and pathogenesis of myocardial lesions in skeletal muscle were much less severe tition for grazing in the more open veld by gousiekte, a cardiotoxicosis of ruminants. PhD thesis, University of Pretoria, Pretoria than in myocardium and of so limited white rhino and, at night, hippopotamus. 6. Young T P 1994 Natural die-offs of large extent as to rule out an alternative diagno- The other is that the buffalo may have mammals: implications for conservation. sis of capture myopathy. been sheltering in the dense woodland to Conservation Biology 8: 410–418

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