Diseases of indigenous chickens in Bokaa village, Kgatleng district, Botswana.

This study examined flock size and management, level of internal and external parasite burden and seroprevalence of antibodies to poultry pathogens in indigenous chickens in Bokaa village, Kgatleng district, Botswana. The mean flock size was 22.6 +/- 6.85 with a range of 11-34. The mean body weights of cocks and hens were 2.28 +/- 0.56 kg and 1.70 +/- 0.38 kg, respectively. Housing and commercial poultry feed were not provided. Ascaridia galli, Heterakis gallinarum and Syngamus trachea were found in some birds. Although the chickens were not vaccinated against any poultry diseases, serum antibodies to Newcastle disease, infectious bursal disease and infectious bronchitis were detected.

Impaction of the stomachs in farmed ostriches (Struthio camelus) in Botswana.

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.

Yolk sac utilization in ostrich (Struthio camelus) chicks.

The mass of residual yolk sac expressed as a percentage of initial mass of the egg from which the chick hatched decreased sharply in the first 2 days post-hatching. A gradual reduction occurred between 3 and 10 days after which a sharp decline was noted between 11 and 13 days post-hatching. The highest number of chicks with unabsorbed yolk sac was noted on day 5 post-hatching followed by days 6 and 7. Chick mortality followed the same pattern. The dynamics, causes and clinical consequences of yolk sac utilization are discussed.

Serum biochemical values of farmed ostrich (Struthio camelus) in Botswana.

Reference biochemical values for serum analytes of 126 clinically normal farmed ostriches on one farm in Botswana were established. These included sodium, potassium, chloride, total protein, albumin, urea, creatinine, uric acid, cholesterol, total bilirubin, conjugated bilirubin, glucose, triglyceride, calcium, phosphorus, manganese, copper, zinc, alkaline phosphatase, gamma glutamyl transferase and creatinine kinase. The values obtained in this study can be used as reference values.

Haemoproteus columbae in domestic pigeons in Sebele, Gaborone, Botswana.

Mature and immature stages of Haemoproteus columbae gametocytes, an avian haemosporidian protozoan parasite were found in 75% of blood smears prepared from 30 healthy domestic pigeons in Sebele location, Gaborone, Botswana. Parenteral administration of an immuno-suppressive dose of dexamethasone, lowered the level of parasitaemia, the packed cell volume and the heterophil:lymphocyte ratio in the test pigeons. However, both the dexamethasone-treated and the control pigeons remained clinically normal.

Helminth parasites of domestic pigeons (Columba livia domestica) in Sebele, Gaborone, Botswana.

Twelve adult domestic pigeons from Sebele, Gaborone, Botswana, were examined for the presence of helminth parasites. The cestode genus Raillietina and two species of nematodes, Dispharynx spiralis and Ascaridia columbae were recovered. Most pigeons (75 %) were infected with Raillietina spp. often in concurrence with A. columbae.

Seroprevalence of Toxoplasma gondii and Chlamydia psittaci in domestic pigeons (Columbia livia domestica) at Sebele, Gaborone, Botswana.

High antibody titres to Toxoplasma gondii and Chlamydophila psittaci were demonstrated in serum collected from domestic pigeons at average titres of 1:128 and 1:64 respectively. The public health implications of these findings are discussed.

Detection of Mycoplasma gallisepticum and Mycoplasma synoviae antibodies in the sera of indigenous chickens by rapid serum agglutination test at Mmopane, Gaborone, Botswana.

The mean flock size was ten chickens per rural farmer. Antibodies to Mycoplasma gallisepticum and Mycoplasma synoviae were detected in 57.88% and 67.33% of the chicken sera respectively.

Seroprevalence of infectious bursal disease in non-vaccinated indigenous and exotic chickens on selected farms around Gaborone, Botswana.

Sera from nine out of 30 (30.0%) apparently healthy unvaccinated indigenous (Tswana) chickens had precipitating antibodies to infectious bursal disease (IBD) virus using the agar gel precipitation test. Similarly, sera from 11 out of 49 (22.4%) chickens of exotic breeds with no history of vaccination against IBD were positive for antibodies against the virus.

Coccidia oocysts in the faeces of farmed ostrich (Struthio camelus) chicks in Botswana.

Coccidia oocysts were demonstrated in the faeces of 53 (about 34%) of 156 apparently healthy ostrich chicks. Young chicks had the highest proportion of infestation while those more than 9 weeks old had no oocysts at all in their faeces. These coccidia may be considered no pathogenic since the infected chicks grew normally without any evidence of diarrhoea.

Antibodies to Newcastle disease virus in the sera of indigenous chickens in Oodi, Kgatleng, Botswana.

A serological survey was conducted to determine the prevalence of antibodies to Newcastle disease virus in apparently healthy and unvaccinated adult indigenous chickens. Haemagglutination inhibiting antibodies to Newcastle disease virus were found in the sera of 51 out of 89 (57.3%) chickens sampled.

The impact of traditional management on seasonal internal parasite burdens and productivity of indigenous Tswana goats in southern Botswana.

Data collected monthly over a period of two years were live weight, packed cell volume (PCV), nematode faecal egg counts (FECs) and coccidial oocyst counts from faecal analyses for 100 mixed age (3-7 years) indigenous Tswana does. The aims of this experiment were to determine seasonal FECs and coccidial oocysts in these goats and quantify the relationships of these burdens to liveweight and PCV. FECs significantly (P < 0.05) varied with season, with the warmer seasons viz spring, summer and autumn having higher log (x + 1) parasite burdens than the cooler winter, while seasonal trends for coccidial oocysts were not obvious. PCV was also significantly (P < 0.05) lower in the warmer seasons than winter. FECs and coccidial oocysts in all seasons were less than the mean log (x + 1) of 3.3 inferred to reduce production in small stock. Correlation coefficients were strongly negative: -0.95 for FECs and liveweight and -0.84 for FECS and PCV, indicating that these worms had a negative impact on productivity. A further study should be conducted to quantify the effects of controlling these parasites during the warm seasons on productivity.

Seasonal fluctuation of parasitic infestation in donkeys (Equus asinus) in Oodi village, Kgatleng District, Botswana.

During the period March to September 2000, a study was conducted in Oodi village, Kgatleng District, Botswana, to investigate the seasonal fluctuation of internal, external and blood parasites of donkeys. Twelve adult donkeys were randomly selected from a farmer with a herd of 15 donkeys. Monthly visits were made to the farmer when the donkeys were examined for parasites. The only ectoparasites recovered from the donkeys were instars of various tick species. The most prevalent tick was Rhipicephalus evertsi evertsi (98.4%), followed by Amblyomma hebraeum and Hyalomma species. The only haemoparasite seen on microscopy was Babesia equi at low parasitaemia in 26.8% of the donkeys. However, no clinical babesiosis was evident. Coprological examination showed the presence of strongyle eggs in moderate numbers. Very low numbers of coccidia oocysts were found in the faecal samples. High tick numbers and worm egg counts coincided with the warm, wet months in contrast to the low numbers recovered during the cold, dry months. An interview conducted by the authors indicated that donkeys were nutritionally marginalised by owners. Supplementary feeding was therefore recommended, especially during the winter months when grazing is poor.

Helminth parasites of indigenous chickens in Oodi, Kgatleng District, Botswana.

Thirteen adult indigenous chickens from Oodi, Kgatleng district, Botswana, were examined for helminth parasites. Two species of nematodes, Ascaridia galli and Heterakis gallinarum, and species of the cestode genus Raillietina, were recovered. A. galli and H. gallinarum were the most commonly seen parasites. The nematode A. galli occurred concurrently with Raillietina spp.

Parasites of domestic pigeons (Columba livia domestica) in Sebele, Gaborone, Botswana.

The following parasites were found in apparently healthy pigeons kept in Sebele: a haemoprotozoan, Haemoproteus columbae (80%); endoparasite metazoan nematodes, Ascaridia columbae (30%) and Dispharynx spiralis (10%); a cestode, Raillietina sp. (80%) and coccidian oocysts (40%); 2 ectoparasites, namely the pigeon fly, Pseudolynchia canariensis (50%) and the louse, Columbicola columbae (30%). The pigeons also had highantibody titres, (1:256) to the protozoan parasite Toxoplasma gondii (100%). The latter infection in these domestic pigeons has public health implications.

A note on endoparasites of wild ostriches (Struthio camelus) in the Mokolodi Nature Reserve, Gaborone, Botswana.

A study was undertaken to investigate the prevalence of endoparasites of wild ostriches at Mokolodi Nature Reserve, Gaborone, over a 7-month period. Large numbers of strongyle eggs were recovered from faecal material in April and September and a decline in the strongyle egg counts was evident during June and July. Noteworthy was the absence of helminth eggs in faecal samples collected from chicks and coccidia oocysts from any of the ostriches.

Growth rate of ostrich (Struthio camelus) chicks under intensive management in Botswana.

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.