African Journals Online
Journal of the South African Veterinary Association

Volume 73, Issue 2, June 2002

Preliminary results on the use of diagnostic ultrasonography as a management tool to quantify egg production potential in breeding ostrich (Struthio camelus australis) females : article
Lambrechts, H.Cloete, S.W.P.Swart, D.Greyling, J.P.C. 48-52

Abstract: An ostrich breeding flock, joined as individual breeding pairs (n = 136 pairs), was used to investigate the possibility of diagnostic ultrasonography as a method to predict the reproductive performance of ostrich females during a breeding season. Follicular activity was easily detected and quantified by using diagnostic ultrasonography. One to 8 follicles were recorded in 25 % of females scanned at the beginning of the 9-month breeding season. At the end of the breeding season, 1-3 follicles were observed in 28.7 % females. Females in which follicular activity was observed came into production earlier than those in which no follicles were observed, with the mean (±SE) number of days to the production of the 1st egg being 22.3 ± 12.5 and 87.4 ± 7.2 days, respectively. Females in which follicular activity was observed at the beginning of the breeding season, produced on average 181 % more eggs during the 1st month of the breeding season (P < 0.01) than females in which no follicular activity was observed (6.67 ± 0.70 vs 2.37 ± 0.41 eggs). Egg production over the first 2 months of breeding and over the entire breeding season were similarly affected (P <0.01), with the mean number of eggs produced over the first 2 months of the breeding season being 14.7 ± 1.5 for females with observed follicular activity and 7.4 ± 0.9 eggs for females with no observed follicular activity. Females in which follicular activity was observed at the end of the breeding season produced on average 108 % more eggs (P<0.01) during the last month of the breeding season than females in which no follicular activity was observed (2.77 ± 0.43 vs. 1.33 ± 0.27 eggs). There was a tendency (P = 0.06) for egg production over the last 2 months to be similarly affected (6.10 ± 0.85 vs 4.19 ± 0.54 eggs). No relationship with egg production over the entire breeding season was found for the end-of-the-breeding-season observations. Diagnostic ultrasonography can thus be used as a management tool to identify reproductively healthy ostrich females and also females with a higher egg production potential over a period of 2 months after or prior to assessment. Future studies should focus on the development of the technique to predict reproductive performance over entire breeding seasons for selection purposes.

The breed prevalence of Dog Erythrocyte Antigen 1.1 in the Onderstepoort area of South Africa and its significance in selection of canine blood donors : article
Van der Merwe, L.L.Jacobson, L.S.Pretorius, J.G. 53-56

Abstract: The blood group antigen Dog Erythrocyte Antigen (DEA) 1.1 is clinically the most important canine blood group as DEA 1.1 antibodies are capable of causing acute haemolytic, potentially life-threatening transfusion reactions. Dogs do not have naturally occurring antibodies to DEA 1.1 but are rapidly sensitised by the first incompatible transfusion. The prevalence of DEA 1.1 in the general dog population is estimated at 42-46 %. Canine blood donors registered with the Onderstepoort Animal Blood Bank (n = 93) as well as potential donors (n = 140) were typed for DEA 1.1 using a monoclonal antibody card kit. All dogs came from the Onderstepoort area, near Pretoria, Gauteng province, South Africa. Overall prevalence of DEA 1.1 was 47 %. Prevalence was 47 % in purebred dogs and 48 % in mongrels. Distinct breed differences were noted with less than 20 % of German shepherd dogs and Boxers and greater than 75 % of Rottweilers, Great Danes, St Bernards and Dalmations testing DEA 1.1 positive. Knowledge of local breed differences will increase effectiveness of blood donor recruitment.

Induction of photosensitivity in sheep with Erodium moschatum (L.) L'Hérit : article
Stroebel, J.C. 57-61

Abstract: Erodium moschatum is an exotic weed in the southern and southwestern coastal areas of the Western Cape Province (WCP), South Africa. It has been suspected as the cause of photosensitivity in sheep. However, attempts to induce photosensitivity by dosing it to sheep have thus far been unsuccessful. During August 1999, 2 sheep suffering from severe photosensitivity were presented for clinical examination to the Western Cape Provincial Veterinary Laboratory (WCPVL). One sheep was sacrificed for autopsy. Except for skin lesions associated with photosensitivity, no icterus or other lesions were present. Histopathological examination of affected skin revealed epidermal necrosis while the liver had no microscopic lesions. It was therefore concluded that the sheep might have been suffering from primary photosensitivity. The farmfrom which the sheep came, situated in the Malmesbury district, WCP, was visited to determine the source of the photodynamic agent. The flock from which the sheep originated had been grazing in a camp where E. moschatum was growing abundantly and had been heavily grazed. Some remaining Erodium in the camp was collected, pulped and dosed over a period of 7 days to an adult sheep. Another sheep was dosed simultaneously with Erodium growing on the premises of the WCPVL. Both sheep developed mild photosensitivity, which was confirmed by histopathological examination of skin biopsies. It was concluded that E. moschatum can induce photosensitivity (probably the primary type) in sheep if ingested in large quantities.

Prevalence of coagulase-negative staphylococci in bovine mastitis in Zimbabwe : article
Kudinha, T.Simango, C. 62-65

Abstract: This study was carried out to determine the prevalence of coagulase-negative staphylococci in clinical and subclinical mastitis in commercial and small-scale farms in Zimbabwe. Thirty five quarter milk samples from clinical mastitis cases and 371 quarter milk samples from cows with subclinical mastitis were cultured for bacterial pathogens. The most frequent pathogens isolated in clinical mastitis were the enteric bacteria (31.4 %), followed by coagulase negative staphylococci (22.9 %) and then Staphylococcus aureus (17.1 %), whereas in subclinical mastitis S. aureus (34.2 %) and coagulase-negative staphylococci were (33.2 %) the most common. Bacillus species were only isolated in milk samples from subclinical mastitis. Coagulase-negative staphylococci were observed in mixed infections with other bacteria in only 2.2 % of the 406 milk samples from clinical and subclinical mastitis where they were isolated together with Bacillus species in 6 of the 9 mixed infection cases. About 95 % of the milk samples from which 131 coagulase-negative staphylococci were isolated had correspondingly high somatic cell counts. The coagulase-negative staphylococci isolated most frequently were S. chromogenes (7.9 %), S. epidermidis (7.4 %) and S. hominis (5.9 %). They were all associated with high somatic cell counts. All the coagulase-negative staphylococci isolates were susceptible to cloxacillin and erythromycin, and more than 90 %of the isolates were susceptible to neomycin, penicillin and streptomycin. The highest resistance was to tetracycline (17.6 %), followed by lincomycin (13.7 %). About 8 % of the isolates were resistant to both penicillin and streptomycin.

Collection of preputial material by scraping and aspiration for the diagnosis of Tritrichomonas foetus in bulls : article
Irons, P.C.Henton, M.M.Bertschinger, H.J. 66-69

Abstract: Two trials were carried out to assess the diagnostic sensitivity and practicability of preputial scraping as a method of collecting preputial material from bulls infected with Tritrichomonas foetus. In the 1st trial, preputial material was collected by simultaneous scraping and aspiration from 3 infected and 1 uninfected bull 10 times over a 5-week period. In the 2nd trial, samples from 5 infected bulls were collected by both sheath washing and scraping on 6 occasions, while 8 uninfected animals were sampled 3 times. Samples were cultured using a modified Trichomonas culture medium (Oxoid). In the first trial, 29 of 30 samples from infected bulls were found to be positive. In the second trial, 83 % of samples collected by both methods tested positive. In neither trial were any samples from the control bulls found to be positive. Scraping was found to be quick and safe, and offered advantages over preputial washing in that urine contamination was easily avoided, samples were smaller and more concentrated and contamination was reduced. It may, however, be subject to greater operator variability than sheath washing. It is concluded that preputial scraping is as effective as washing and represents a suitable alternative for the collection of material for direct examination and culture of Tritrichomonas foetus.

A questionnaire survey of the management and use of anthelmintics in cattle and antelope in mixed farming systems in Zimbabwe : article
Madzingira, O.Mukaratirwa, S.Pandey, V.S.Dorny, P. 70-73

Abstract: A survey of the management of mixed farming of cattle and antelope and use of anthelmintics was conducted on eleven farms between August and December 1999 by a self-administered questionnaire. Seventeen antelope species ranging from grey duikers (Sylvicapra grimmia) to eland (Taurotragus oryx) occurred on the farms. Impala (Aepyceros melampus) was the most abundant antelope on the farms. Seventy-five per cent of the antelope species on the farms were grazers and mixed feeders and shared grazing with cattle. Most farmers (n =8) did not consider the stocking density for cattle and antelope as an important management factor. Fifty-four per cent of the farmers (n = 6) routinely dewormed both cattle and antelopes. Albendazole and fenbendazole were the most commonly used drugs for deworming cattle (72.7 %) and antelope species (54.5 %). The deworming of antelope was carried out during the dry season, using albendazole-, fenbendazole-and rafoxanide-medicated supplementary feed blocks. Doramectin injections were given to antelopes on two farms. Cattle were dewormed preventively and according to the general body condition of the animal. Few farmers (n = 4) followed the recommended deworming programme for cattle in Zimbabwe and only one farmer followed a specified dosing programme for game. However, results from the survey on the deworming of game indicate that farmers perceived helminth infections in antelope to be important.

Protective effect of clenbuterol on duodenal epithelium during food restriction in rats : research communication
Cardoso, L.A.Ferreira, M.L. 74-76

Abstract: The aim of the study was to examine the effect of the _2-adrenoceptor, clenbuterol, on the duodenal epithelium of food-restricted rats. Clenbuterol was administered as a dietary admixture (4 mg/kg diet) to three groups of male Wistar rats (n =8) housed individually in metabolic cages and fed ad libitum for 15 days at 110 %and 160 %of the estimated requirement for energy maintenance. Untreated groups at each energy intake level were also included. Samples of the duodenum were examined by light microscopy. Compared with control animals, clenbuterol treatment significantly increased body mass in all diet groups, although it induced no changes in mean food intake. Gastrointestinal (GIT) dry mass was increased by clenbuterol only in the most severely-restricted-diet group. In this group, clenbuterol treatment increased GIT tissue nitrogen (23 %), more than it did in the ad libitum group (13 %). In all treated groups, clenbuterol induced significant hypertrophy of duodenal enterocytes and circular muscle layers, and the diameter of lymphatic vessels increased. In the clenbuterol-treated, restricted-diet groups the height of the brush borders of enterocytes increased. It is concluded that clenbuterol has a protective effect on the intestinal structure in rats on restricted as well as ad libitum diets.

Apparent idiopathic interface disease in a Boer billy goat : short communication
Yeruham, I.Zamir, S.Perl, S.Garazi, S. 77-78

Abstract: An apparently idiopathic interface disease in a 2-year-old Boer billy goat is described. Clinical features of the disease were the presence of a pruritic multiple focally disseminated dermatitis with flat-topped, angular, scaly plaques and papules with corrugated surfaces in the skin of virtually the entire body. The aetiology of the disorder in the described case is unknown.

The use of liposomal amphotericin B in the management of Xylohypha bantiana mycosis in a dog : case report
Leisewits, A.L.Rademeyer, C.Picard, J. 79-82

Abstract: Xylohypha bantiana is a rare neurotropic fungal infection reported in humans, dogs and cats. In dogs it has only been identified on post mortem examination and thus no successful treatments have previously been reported. Amphotericin B is a potent antifungal drug with a low therapeutic index because of its nephrotoxicity. Liposomal encapsulation of the drug has resulted in much safer use in humans. This article reports a case of Xylohypha bantiana infection in a dog that was diagnosed antemortally and managed with liposomal amphotericin B, which resulted in the prolongation of quality of life for an infection that invariably results in rapid death.

Renal T-cell lymphoma with cerebral metastasis in a dog with chronic canine ehrlichiosis : case report
Lane, E.P.Lobetti, R.G. 83-85

Abstract: A renal T-cell lymphoma with exclusive cerebral metastasis was diagnosed in a 5-year-old Staffordshire bull terrier bitch euthanased for aggression. This is the first recorded case of primary renal lymphoma in a dog. Immune suppression, due to chronic canine monocytic ehrlichiosis, mayaccount for the unusual primary site and metastatic patternof the tumour.

A severe case of contagious ecthyma in Tswana goats : case report
Baipoledi, E.K.Nyange, J.F.C.Hyera, J.M.K. 86-87

Abstract: The first severe case of caprine contagious ecthyma (parapox) in Tswana goats is described from Botswana. Affected animals were indigenous adult Tswana goats. The case involved a flock of 12 goats of which 4 (33.3 %) were very severely affected but none died. The lesions were confined to the head and included swollen lips, swollen submandibular lymph nodes, gingivitis, glossitis, ulceration on lip and gum mucosae and scab formation on ulcerated areas. No lesions were found on other parts of the body. This case was clinically indistinguishable from bluetongue.