Search

Limb deformities were detected in 135 out of 885 ostrich chicks, giving a prevalence of 15.3%. Tibiotarsal rotation affected 73% of the chicks with limb deformities, whereas rolled toes accounted for 36%. The right leg was more often affected than the left leg. The incidence of limb deformities was highest in 2- to 3-week-old ostrich chicks. The incidence of limb deformities was highest at the beginning of the breeding season and lowest towards the end, when it was relatively warmer. The mean serum manganese and zinc levels in deformed ostrich chicks were higher than the levels reported for normal chicks.

Thirty-seven ostrich chicks raised artificially had their weights, lengths of metatarsus and heights measured weekly from hatching to the 16th week. Despite weight loss during the first week due to utilization of egg yolk by the chicks, the chicks showed and exponential growth up to the twelfth week with an overall mean weekly weight gain of 1.3 kg. Female chicks showed a superior mean weekly gain of 1.6 kg compared to 1.2 kg for males. The metatarsal length grew rapidly at a weekly rate of 2.5 cm, but began to decline in the 11th week even though the weights and heights of the chicks were still increasing. The correlation coefficient between body weight and metatarsal length was 0.97. Individual chicks also maintained their respective heavy or light weight hierarchies throughout the study period. Thus isolation of chicks into groups by weight and raising them separately could have a role in the artificial rearing of ostrich chicks. Furthermore, ostrich chick rearing may be improved by regularly weighing chicks as a means of detecting changes in the growth patterns.

Four adult ostriches developed sudden onset paresis and were unable to stand up when disturbed. After treatment with selenium and vitamin E, one of the birds could stand and move normally. The others died and post mortem examination revealed pale patches in the thigh muscles. Histopathological examination showed degeneration of skeletal muscles as seen in nutritional myopathy. Serum selenium and vitamin E levels were low whereas aspartate aminotransferase and creatine kinase levels were very high. All remaining birds on the farm were given multimineral and vitamin E supplement and no more cases were seen.

Mushi, E.Z., Isa, J.F.W., Chabo, R.G., Binta, M.G., Sakia, R.M. and Kapaata, R.W., 1998. Culicoides associated with dairy cows at Sebele, Gaborone, Botswana. Tropical Animal Health and Production, 30(5), 305^307 Culicoides spp. (Diptera: Ceratopogonidae) are important as vectors of viral diseases such as bluetongue, African horse sickness, equine encephalosis and bovine ephemeral fever (Meiswinkel et al., 1994). Culicoides of many species have been recorded from southern Africa but Botswana has remained unsampled for biting midges (Meiswinkel et al., 1994). We report on the abundance and species composition of Culicoides collected in a light trap placed next to a herd of dairy cows at Sebele, Gaborone, Botswana. This is the ¢rst report on the collection and identi¢cation of Culicoides associated with dairy cows in Botswana. The collection site was at Sebele, near Gaborone, at 24833’S, 25857’E and an altitude of 994 m. Most of the rain falls in summer from November to March and averages above 500 mm annually (Botswana Metereological Services). A single 220 volt 8 W ultraviolet down-draught suction light insect trap obtained from the Onderstepoort

Impaction of the proventriculus, gizzard, and sometimes intestines due to sand was confirmed at postmortem in 25 cases involving ostriches (Struthio camelus). Although there was no age predisposition, impaction was more common in juvenile over 3 mo old. Clinical signs included sternal recumbency, outstretched neck, debility, and inability to stand. Palpation of the impacted stomachs gave a gritty sensation. Depletion of coronary fat was a consistent postmortem finding. The most common material causing impaction was sand. This report highlights impaction as one of the major causes of debility and death in intensively farmed ostriches. High levels of alkaline phosphatase coupled with low levels of plasma glucose, protein, and albumin detected in impacted ostriches may be useful diagnostic antemortem indicators of the syndrome.