Transmission studies on Trichinella species isolated from Crocodylus niloticus and efficacy of fenbendazole and levamisole against muscle L1 stages in Balb C mice

Forty four Balb C mice, aged 18 weeks were infected with crocodile ( Crocodylus niloticus)-derived Trichinella species. Of the infected mice, 32 were randomly divided into two groups each containing equal numbers of males and females; levamisole treated group and fenbendazole treated group. Each group was randomly subdivided into two subgroups as follows: levamisole group (subgroup 1: treated with levamisole on day 35 post infection and subgroup 2: treated with levamisole on days 35 and 42 post infection) and fenbendazole group (subgroup 1: treated with fenbendazole on day 35 post infection and subgroup 2: treated with fenbendazole on days 35 and 42 post infection). The first sub-groups treated on day 35 post infection were slaughtered on day 42 post infection and the second subgroups were treated on days 35 and 42 post infection and slaughtered on day 49 post infection. Two female mice were infected a day after mating and were slaughtered together with the offspring on day 64 post-infection. Ten infected control mice were given 1 ml distilled water orally as placebo, and five of these were slaughtered on day 42 post infection. The results showed that the mean reproductive capacity index of this strain (RCI) in Balb C mice was 110. There was a significant reduction ( P<0.01) in larval counts in the single treatment groups (day 35) and in the double treatment groups (days 35 and 42) for both anthelmintics when compared the number of parasites in the control groups. After a single treatment, levamisole reduced the infection by 79.9% and fenbendazole by 76.7%. Following double treatments, levamisole reduced the infection by 95.5% and fenbendazole by 99.1%. There was evidence that the infected pregnant mice transmitted the parasite to their offspring. It is not certain whether the parasite was transmitted congenitally or transmammary. Alternative ways of controlling the parasite in crocodile farms in Zimbabwe are discussed.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Research Board of the University of Zimbabwe.mn201

The epidemiology of rabies in Zimbabwe. 2. Rabies in jackals (Canis adustus and Canis mesomelas)

The epidemiology of rabies in Canis adustus (the side-striped jackal) and Canis mesomelas (the black-backed jackal) in Zimbabwe is described using data collected from 1950-1996. Cases in the two species made up 25,2% of all confirmed cases, second only to domestic dogs. Since the species of jackal cases was not recorded on rabies submission forms, the country was divided into areas according to species dominance and jackal cases were assigned to either C. adustus or C. mesomelas dominant zones or a sympatric zone where the relative status of the species is not known. Jackal rabies in both species is maintained in the commercial farming sector. Jackal rabies in the C. adustus zone occurs as dense epidemics, which begin at a single focus and spread centrifugally. The foci were initiated by rabid dogs, but once initiated the epidemic is maintained by C. adustus independently of other species. The extent of outbreaks in the C. adustus zone was limited by geographical (Ianduse type and jackal species interface) boundaries. Jackal rabies in C. adustus zones showed two seasonal peaks with the main peak occurring during late summer and the second peak during winter. In the C. mesomelas zone jackal rabies was more sparse but it occurred during most years. C. mesomelas is also able to maintain rabies independently of other species, although the epidemiology of the disease in this species is unclear. Transmission of rabies cycles between the two jackal species zones does not appear to occur as epidemics terminate when crossing the C. adustus and C. mesomelas interface boundaries.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Mycoplasma-associated polyarthritis in farmed crocodiles (Crocodylus niloticus) in Zimbabwe

Outbreaks of polyarthritis in farmed crocodiles (Crocodylus niloticus) on five farms in Zimbabwe are described. Cases were reported only among the rearing stock aged 1-3 years. No breeding stock suffered. Morbidity was about 10% and the mortality even lower. All the sick animals consistently displayed swollen limb joints as well as progressive lameness and paresis. The synovial structures in subacute cases contained mycoplasmas and excess turbid mucus which, at a later stage of the disease, became yellowish, inspissated and sterile. Cellular changes in the joint capsule included oedema, necrosis of the superficial layers of membrane, lymphocytic infiltration and fibrosis. Evidence of pneumonia was observed only at necropsies. Fifteen isolates of Mycoplasma were cultured from the clinical specimens collected from the four sick and three dead crocodiles. The affected joints of all these animals yielded Mycoplasma in pure culture, but the culture from lungs yielded post-mortem invaders also. The sick animals were treated with a single intramuscular injection of long-acting tetracycline(10 mg/kg), and oxytetracycline mixed in feed at 550 mg/kg was fed for 10 d. The treatment appeared to be effective in ameliorating the clinical signs, but in some cases inflammatory swelling persisted. All 15 the isolates conformed to the characteristics of the genus Mycoplasma, and were serologically indistinguishable in growth-inhibition (GI) tests. Although these isolates shared the main biochemical characteristics of Mycoplasma capricolum, they differed serologically. Also goats were refractory to experimental infection with crocodile strains. In crocodile yearlings, however, the disease was reproduced with an isolate from one of the affected farms. The source of infection remained elusive. The farmers suspected poultry meat fed to the crocodiles to be the source. However, GI tests failed to identify the isolates as one of the pathogenic glucose-metabolizing avian mycoplasmas. This appears to be a first report of isolation of Mycoplasma from crocodiles and also of its association in disease.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

The epidemiology of rabies in Zimbabwe. 1. Rabies in dogs (Canis familiaris)

The epidemiology of rabies in dogs in Zimbabwe is described using data from 1950, when rabies was re-introduced after a 37 -year absence, to 1996. Dogs constituted 45,7% of all laboratory-confirmed rabies cases and were the species most frequently diagnosed with the disease. Slightly more cases were diagnosed from June to November than in other months. From 1950 to the early 1980s, most dog cases were recorded from commercial farming areas, but since the early 1980s most have been recorded from communal (subsistence farming) areas. This change appears to be due to improved surveillance in communal areas and not to any change in the prevalence of rabies. Dog rabies therefore appears to be maintained mainly in communal area dog populations, particularly the large communal area blocks. Urban rabies was not important except in the city of Mutare. Where dog rabies prevalence was high, the disease was cyclic with periods between peak prevalence ranging from 4- 7 years. Dog rabies cases were, on the whole, independent of jackal rabies and rabies in other carnivores. There was a significant negative relationship between the annual number of rabies vaccine doses administered nationally to dogs and the annual number of dog rabies cases lagged by one year, indicating that the past levels of immunisation coverage have had a significant effect on the number of rabies cases. However, dog vaccination coverage has clearly not been adequate to prevent the regular occurrence of rabies in dogs.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Jackal rabies in Zimbabwe

The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Relationship between burden of infection in ungulate populations and wildlife/livestock interfaces

In southern African transfrontier conservation areas (TFCAs), people, livestock and wildlife share space and resources in semi-arid landscapes. One consequence of the coexistence of wild and domestic herbivores is the risk of pathogen transmission. This risk threatens local livelihoods relying on animal production, public health in the case of zoonoses, national economies in the context of transboundary animal diseases, and the success of integrated conservation and development initiatives. The level of interaction between sympatric wild and domestic hosts, defining different wildlife/livestock interfaces, characterizes opportunities of pathogen transmission between host populations. Exploring the relationship between infection burden and different types of wildlife/ domestic interfaces is therefore necessary to manage the sanitary risk in animal populations through control options adapted to these multi-host systems. Here, we assessed the infection burdens of sympatric domestic cattle (Bos taurus/Bos indicus) and African buffalo (Syncerus caffer) at an unfenced interface and compared the infection burdens of cattle populations at different wildlife/ livestock interfaces in the Great Limpopo TFCA. Patterns of infection in ungulate populations varied between wild and domestic hosts and between cattle populations at different wildlife/livestock interfaces. Foot-and-mouth disease, Rift Valley fever and theileriosis infections were detected in buffalo and cattle at unfenced interfaces; bovine tuberculosis was only present in buffalo; and brucellosis and lumpy skin disease only in cattle. At unfenced interfaces, cattle populations presented significantly higher Theileria parva and brucellosis prevalence. We hypothesize that cattle populations at wildlife/livestock interfaces face an increased risk of infection compared to those isolated from wildlife, and that the type of interface could influence the diversity and quantity of pathogens shared. Additional host behavioural and molecular epidemiological studies need to be conducted to support this hypothesis. If it is confirmed, the management of wildlife/livestock interfaces will need to be considered through the prism of livestock and public health.The European PARSEL project (No. Food 2007 137-950) and by the Ministère Français des Affaires Etrangères through the French Embassy in Zimbabwe (RP-PCP grants 2008 and 2009).http://journals.cambridge.org/action/displayJournal?jid=HYGam201

Rabies in southern Africa

The first confirmed outbreak of rabies in Africa, believed to have followed the importation of an infected dog from England in 1892, occurred in the eastern Cape Province of South Africa, and was brought under control in 1894. An unconfirmed epidemic of rabies in dogs occurred in western Zambia in 1901. By the following year the disease had apparently spread along a major trade route, to cause an outbreak in Zimbabwe which engulfed most of the country before being eradicated in 1913. The existence of endemic rabies of viverrids (mongooses and genets) was confirmed in South Africa in 1928, and since then the viverrid disease has continued to occur widely on the interior plateau of the country with spill-over of infection to cattle and a variety of other animals. From about 1947 onwards, an invasive form of dog rabies spread from southern Zambia and/or Angola into Namibia, across northern and eastern Botswana into Zimbabwe and the northern Transvaal by 1950, entered Mozambique in 1952, and spread from there to Swaziland in 1954. Dog rabies extended from southern Mozambique into Natal in 1961 to cause a major epidemic which was brought under control in 1968. The disease re-entered northern Natal from Mozambique in 1976 and since then dog rabies has proved difficult to control in the peri-urban settlements of Natal-KwaZulu. The disease spread from Natal to Lesotho in 1982, and into the Transkei region of the eastern Cape Province in 1987, to reach the Ciskei by 1990. The spread of the disease in dogs was followed by the emergence of rabies of jackals and cattle in central Namibia, northern Botswana, Zimbabwe and the northern Transvaal. A unique outbreak of rabies in kudu antelope occurred in central Namibia from 1977 to 1985, apparently involving oral spread of infection between individuals. A few cases of rabies in the bat-eared fox were recognized each year in Namibia from 1967 onwards, and from the 1970s the occurrence of the disease in the fox has emerged as a distinct problem in the northern Cape Province and spread to the west coast. The rabies-related viruses, Lagos bat, Mokola and Duvenhage, associated with bats, shrews and rodents in Africa, are known to have caused isolated cases of disease in South Africa, and on one occasion a small outbreak involving six cats and a dog in Bulawayo, Zimbabwe. However, the results of monoclonal antibody tests on numerous specimens indicate that the rabies-related viruses are not a major cause of disease in southern Africa.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn2014mn201

Oral rabies vaccination of jackals : progress in Zimbabwe

Work on the development of an oral vaccination system for jackals is underway at the Veterinary Laboratory (Diagnostics and Research Branch), Zimbabwe. It is anticipated that the system will be used to control the large rabies epidemics that occur in jackals in Zimbabwe.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Gousiekte in African buffalo (Syncerus caffer)

Three African buffalo (Syncerus caffer) that died after capture and translocation from Mutirikwe Recreational Park in southern Zimbabwe showed macroscopic and microscopic lesions of cardiomyopathy compatible with a diagnosis of gousiekte. The buffalo had had access to Pavetta schumanniana, a plant that is known to cause gousiekte. Death was attributed to cardiac failure as a result of previous consumption of the plant, exacerbated by the stress of translocation

Vaccination to control an outbreak of Mycoplasma crocodyli infection

Details of a severe outbreak of M. crocodyli infection in farmed crocodiles are reported. The outbreak was suspected to have been precipitated by translocation-related stress on the animals brought from a farm with a known history of M. crocodyli infection. Resorting to the use of an autogenous vaccine proved more effective in alleviating the disease manifestations than antibiotic therapy. Prospects of vaccination in the face of an outbreak are discussed.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201