African Journals Online
Journal of the South African Veterinary Association

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Volume 71, Issue 3, September 2000

Feline panleukopenia virus revisited : molecular characteristics and pathological lesions associated with three recent isolates : article
Van Vuuren, M.Steinel, A.Goosen, T.Lane, E.Van der Lugt, J.Pearson, J.Truyen, U
140-143

Abstract: The low incidence of clinical signs or pathological lesions compatible with feline panleukopenia in cats has created the perception among practitioners that the disease has disappeared since the emergence of canine parvovirus type 2 in the late 1970s.Three parvoviruses that were recently isolated from a domestic cat and 2 cheetahs in cell culture or detected by means of the polymerase chain reaction were shown to be typical feline parvoviruses. Phylogenetic comparison with other FPV isolates did not reveal a particular African cluster.

A study to evaluate the field efficacy of ivermectin, fenbendazole and pyrantel pamoate, with preliminary observations on the efficacy of doramectin, as anthelmintics in horses : article
Davies, J.A.Schwalbach, L.M.J.
144-147

Abstract: The efficacy of ivermectin, fenbendazole, pyrantel pamoate and doramectin was evaluated under field conditions at 2 sites in the Free State Province of South Africa. The study involved 25 horses at each site, divided into 5 groups of equal size. Ivermectin, fenbendazole and pyrantel pamoate were administered orally at doses of 0.2, 10 and 19 mg/kg respectively. Doramectin was administered by intramuscular injection at a dose of 0.2 mg/kg. Treatment efficacy was based on the mean faecal egg count reduction 14 days post treatment. At site A a faecal egg count reduction of 100 % was found after treatment with ivermectin, fenbendazole and doramectin. A 96.1 % reduction was found after treatment with pyrantel pamoate. At site B ivermectin and doramectin produced a 100 %reduction in faecal egg counts, fenbendazole produced an 80.8 % reduction and pyrantel pamoate a 94.1 %reduction. Doramectin produced a 100 %reduction in faecal egg counts at both sites, despite not being registered for use in horses. In addition, the results indicated reduced efficacy of fenbendazole at site B, which suggested benzimidazole resistance. Larval cultures showed that cyathostomes accounted for between 86 and 96 %of pre-treatment parasite burdens at both sites. Other helminths identified in the faecal samples were Strongylus spp. and Trichostrongylus axei.

A preliminary evaluation of a sheep blowfly trap in the Western Cape : article
Scholtz, A.J.Cloete, S.W.P.Laubscher, J.M.De Beer, E.F.
148-152

Abstract: An insecticide-free sheep blowfly trapping system, utilising a synthetic lure, was evaluated at 4 localities in the Western Cape. Control sites, where no suppression was practised, were identified for each locality. The blowfly population was monitored for 48 hours monthly at each of the localities. Five to 7 suppression traps at the respective localities were identified for this purpose. Three to 10 traps were set monthly for monitoring in the control areas. Trapping resulted in the suppression (P <0.01) of the Lucilia population at Caledon, where a large area of approximately 50 km 2 was trapped. The suppression area of all the localities was =850 ha. At Elsenburg, blowfly numbers were low. There was a strong suggestion of a general reduction in the Lucilia numbers at this locality. Trapping failed to reduce Lucilia numbers at Tygerhoek and Langgewens. Lack of control over the influx of Lucilia from adjacent sheep-producing areas probably contributed to this result. The observed response at Elsenburg was probably due to its situation in a predominantly wine-growing area. Most of the blowflies recovered from the control traps during the month with the highest yield at the respective localities belonged to the genus Lucilia. The results obtained at Caledon and published reports suggest that large-scale trapping of Lucilia spp. may play a role in an integrated pest management system for blowflies.

Clinical, cardiopulmonary and haemocytological effects of xylazine in goats after acute exposure to different environmental temperature and humidity conditions : article
Mogoa, E.G.M.Stegmann, G.F.Guthrie, A.J.Swan, G.E.
153-159

Abstract: This study was carried out to assess the influence of xylazine administration on clinical, cardiopulmonary and haemocytological variables after acute exposure to different environmental conditions. Xylazine hydrochloride was administered intravenously at 0.1 mg/kg body mass to 6 clinically healthy, castrated male goats. All animals were exposed for 60 min to 3 sets of climatic conditions: 14 ºC, 33 %relative humidity; 24 ºC, 55 %RH, and 34 ºC, 65 % RH. The variables that were measured for a period of 60 min after xylazine administration were sedation, analgesia, salivation, urination, ventilation rate, heart-rate, mean arterial blood pressure, oesophageal temperature, haematocrit, mean corpuscular volume and mean corpuscular haemoglobin concentration. Xylazine induced sedation, analgesia, salivation and urination independently of the 3 environmental conditions. Environment had no influence on the onset, duration and recovery from sedation. In the 14 ºC environment, xylazine resulted in a significant decrease in ventilation and heart-rate from baseline values. Significant changes in mean arterial blood pressure, haemoglobin concentration, mean corpuscular volume, haematocrit and red cell count were observed in the 3 environments. Total plasma protein was significantly altered at 24 ºC and 34 ºC. Acute exposure of goats to different environmental conditions had no significant influence on the clinical, cardiopulmonary and haemocytological variables. Physiological changes induced by xylazine were therefore independent of the environment.

Characteristics and performance of village animal health workers and veterinary assistants in northern Malawi : article
Huttner, K.Leidl, K.Jere, F.B.D.Pfeiffer, D.U.
160-165

Abstract: Fourty-two village animal health workers called keymen (KM) and 84 veterinary assistants (VA) involved in a Basic Animal Health Service (BAHS) Programme in northern Malawi were interviewed during 1998. The general characteristics and perceptions of both groups were analysed using uni- and multivariate techniques. Detailed sales and treatment patterns of six KMand 12 VAwere evaluated for the period September 1996 to August 1997. Results indicated an overall job-satisfaction for 82 % of KM and 83 % of VA. Estimated weekly involvement in livestock service delivery, particularly of KM, was 3.7 days on average. Total annual drug sales of KM and VA between 1996 and 1997 on average were equivalent to US$ 124 and US$ 218 respectively. Most livestock remedies were issued for treatment of calves, followed by adult cattle, chickens and small ruminants. The changes suggested by VA and KM in order to improve field performance focused on regular refresher training by the BAHS programme.

Routine veterinary anaesthetic management practices in South Africa : article
Joubert, K.E.
166-172

Abstract: A survey of the routine anaesthetic management of dogs and cats during sterilisation by veterinarians in South Africa was conducted. This report describes the premedication, induction and maintenance agents most commonly used in dogs and cats. Information about monitoring of patients during the procedure and who is responsible for induction of anaesthesia and monitoring was obtained. Questionnaires were analysed with regard to demographic data, practice size, continuing education, the number of surgical procedures and sterilisations performed per week and an estimate of yearly mortality. Acetylpromazine is the most commonly used premedication in dogs and xylazine in cats. Thiopentone in dogs and alphaxalone/alphadolone in cats were the induction agents most commonly used. Alphaxalone/alphadolone in cats and halothane in dogs are the most commonly used maintenance agents. Records of anaesthesia are poorly kept and monitoring of patients is poorly performed. Respiratory rate is the parameter most commonly monitored (90.7 %), and in most cases is the sole parameter. On average 10.34 ± 8.25 cats were operated per week, of which 5.45 ±5.60 were sterilised; 17.79 ±11.61 dogs were operated per week, of which 8.65 ±7.10 were sterilised. In total, 190 patients died under anaesthesia, a mortality rate of 1:1243. Just over 50 % of practitioners had attended continuing education courses during their careers.

The spread of weeds into sensitive areas by seeds in horse faeces : article
Van Dyk, E.Neser, S.
173-174

Abstract: The possible spread by horse faeces of plants that may become weeds in sensitive areas was investigated. It was found that the period 24-48 hours after ingestion of seeds included in rations was the retention time for seeds passing through the digestive system of the horse. The ability of seeds to germinate was not influenced by exposure to digestive fluids or sea-water. A feeding regime of compound feeds is suggested.

Ectoparasites of dogs belonging to people in resource-poor communities in North West Province, South Africa : article
Bryson, N.R.Horak, I.G.Hohn, E.W.Louw, J.P.
175-179

Abstract: A total of 344 dogs belonging to people in resource-poor communities in North West Province, South Africa, was examined for ectoparasites, and all visible arthropods were collected from the left side of each dog. By doubling these numbers it was estimated that the dogs harboured 14 724 ixodid ticks, belonging to 6 species, 1028 fleas, belonging to 2 species, and 26 lice. Haemaphysalis leachi accounted for 420 and Rhipicephalus sanguineus for 14 226 of the ticks. Pure infestations of H. leachi were present on 14 dogs and of R. sanguineus on 172 dogs. Small numbers of Amblyomma hebraeum, R. appendiculatus, R. evertsi evertsi and R. simus were also collected. The predominance of R. sanguineus accounts for the high prevalence of canine ehrlichiosis (Ehrlichia canis) within the survey region, compared to canine babesiosis (Babesia canis), which is transmitted by H. leachi, and is a much rarer disease.

Survey of canine babesiosis in South Africa : article
Collett, M.G.
180-186

Abstract: A questionnaire, designed to obtain qualitative information on a number of variables concerning canine babesiosis (biliary fever) in South Africa, was sent to 510 veterinary practices in late 1993. Of the 157 practices that responded, all were presented with cases of babesiosis and most were situated in Gauteng, the Western Cape and KwaZulu-Natal. Apart from the Western Cape, a winter-rainfall region, the prevalence of babesiosis cases in dogs was highest in summer. Most of the respondent practices treated between 1000 and 5000 sick dogs that included 100 to 500 babesiosis cases each year. Respondents identified cerebral babesiosis, enterorrhagia, `red' or haemoconcentrated babesiosis, acute renal failure and pulmonary babesiosis or `shock lung', amongst others, as the most prevalent forms of complicated (`atypical') babesiosis. Diminazene, imidocarb and trypan blue were the most popular antibabesials. Trypan blue was most often used in shocked patients, whereas diminazene and imidocarb were preferred when there was a high parasitaemia in the absence of shock. At least 19 antibabesial treatment regimens were used in practices. These comprised the use of single doses of antibabesial drugs; split doses with repeat injections, and combined drug variations, some of which are undesirable due to possible sterilisation of Babesia infection or potential toxicity. Side-effects were most commonly associated with imidocarb use. Ninety-six percent of respondents used supportive treatment (e.g. corticosteroids, vitamins and `liver support') in all cases of babesiosis. The use of blood transfusion as supportive treatment varied according to practice and severity of the case. Most practices never cross-matched blood to be transfused, and transfusion reactions were rare. Diminazene was most frequently incriminated in cases where drug `resistance' or relapses occurred. Cerebral and `red' cases resulted in high mortality. Treatment of babesiosis costs the dog-owning public in South Africa more than R20 million each year. Information on the distribution and possible complicating role of Ehrlichia canis was obtained. Development of a vaccine was the first research priority identified.

Helicopter-based censusing of domestic dogs in Gauteng Province, South Africa : article
Reilly, B.K.Van der Vyver, F.
187-191

Abstract: Decision support in veterinary epidemiology often depends on density estimates of domestic animals. These estimates are usually based on ground surveys of various types. Ground surveys are difficult to undertake in the informal housing settlements that are frequently encountered in developing countries. In addition, they are time-consuming and expensive. In this study, field experience in enumerating wildlife from helicopters was used to count domestic animals in Gauteng Province, South Africa. Data for domestic dogs are analysed for precision and accuracy and the technique evaluated in terms of its value for decision support.

The measurement of glucocorticoid concentrations in the serum and faeces of captive African elephants (Loxodonta africana) after ACTH stimulation : research communication
Stead, S.K.Meltzer, D.G.A.Palme, R.
192-196

Abstract: Conventionally, the assessment of adrenal responses to stress relies on blood sample collection. However, blood collection from animals is impossible without restraint or immobilisation that influences results. This study was undertaken to validate recently established enzyme immunoassays that measure faecal glucocorticoid metabolites in elephants, and to perform a preliminary investigation into the biological relevance of this non-invasive method for use in assessing the degree of stress in this species. Four juvenile African elephants were injected i.m. with 2.15 mg synthetic adrenocorticotrophic hormone (Synacthén, Novartis, Switzerland). Blood and faecal samples were collected over 4 h and 7 d respectively. Concentrations of serum cortisol and faecal cortisol metabolites were determined using immunoassay. Variability of basal and peak values in blood and faeces was observed among the elephants. After ACTH injection, serum cortisol concentrations increased by 400-700 %. An 11-oxoaetiocholanolone enzyme immunoassay (EIA) proved best suited to measure cortisol metabolites (11,17-dioxoandrostanes) when compared to a cortisol and corticosterone EIA in faecal samples. Concentrations of faecal 11,17-dioxoandrostanes increased by 570-1070 %, reaching peak levels after 20.0-25.5 h. Greater levels of glucocorticoid metabolites were measured in faecal samples from elephants kept in small enclosures compared to levels in the faeces of animals ranging over a larger area. The results of this preliminary study suggest that non-invasive faecal monitoring of glucocorticoid metabolites is useful in investigating adrenal activity in African elephants.

Dirofilaria repens in a cat with acute liver failure : case report
Schwan, E.V.Miller, D.B.De Kock, D.
197-200

Abstract: Acute liver failure was diagnosed in a 12-year-old cat. Fine needle aspirate cytology revealed high numbers of unsheathed microfilariae and a hepatocellular reaction with no evidence of bacterial infection. The microfilariae were identified as those of Dirofilaria repens by acid phosphatase staining. The high number of microfilariae seen in both the blood and the liver aspirate samples as well as the favourable response to ivermectin amongst other drugs administered, is suggestive that D. repens was the cause of the liver insult. A positive result obtained with an antigen-capture ELISA (Dirochek ®) for Dirofilaria immitis antigen was interpreted as false. This is the 1st report of Dirofilaria repens for South Africa.

Bovine mastitis therapy and why it fails : continuing education
Du Preez, J.H.
201-208

Abstract: Treatment of bovine mastitis depends on the cause, the clinical manifestation and the antibiotic susceptibility of the agent. Mastitis therapy is commonly unsuccessful owing to pathological changes that occur in the udder parenchyma as a result of the inflammatory reaction to mastitogenic bacteria, pharmacokinetic properties of antimicrobial mastitis drugs, mastitogenic bacterial and related factors, and poor animal husbandry and veterinary interventions.