Between January 1982 and December 1989 more than 5,000 clinical cases of bovine parasitic otitis were examined. Clinical signs were mild in early cases and were characterised by dullness, anorexia and occasional head shaking, but were severe in long standing cases where the major presenting clinical signs were dark brown aural discharges which soiled the hair below and in front of the ear, emaciation, central nervous signs, recumbency and death.

Aim:Echinococcosis or hydatidosis (due to the larval stage of Echinococcus spp.) and cysticercosis (due to the larval stage of Taenia hydatigena) pose a significant economic losses due to slaughter condemnation and risk to public health in developing countries such as Tanzania where sanitation is poor and people live in close proximity with each other and with animals. This study was conducted to determine the prevalence of and to identify the predisposing factors for echinococcosis and cysticercosis in sheep and goats at three slaughter slabs located in the livestock-wildlife interface areas of Ngorongoro, Tanzania.Materials and Methods:A cross-sectional based survey was conducted, from January 2013 to April 2013, whereby a total of 180 animals comprising 90 goats and 90 sheep of both sexes were examined at postmortem for the evidence of larval stages of Echinococcus spp. (hydatid cyst) and T. hydatigena (Cysticercus tenuicollis) through visual inspection, incision and palpation of organs and viscera.Results:The prevalence of echinococcosis was 22.2% and 16.6%, in goats and sheep, respectively, while the overall infection rates for cysticercosis were 61.1% in goats and 42.2% in sheep. The result of this study revealed that goats and sheep in Malambo slaughter slab had significantly higher prevalence of T. hydatigena (C. tenuicollis) and hydatid cysts (p<0.05) compared to other slab points. T. hydatigena (C. tenuicollis) cysts were more frequently detected in the omentum than other visceral organs among the animals examined.Conclusion:In conclusion, the observed high prevalence of the two metacestodes larval stages leads to high condemnation rates of edible offals and raises significant public health concerns. This underscores for the need to undertake more extensive epidemiological investigations to better determine the causal factors, economic impact, and public health importance of the disease in this livestock-wildlife interface setting.

Nicotine used at approximately 2 ppm in 0.25% toxaphene dip wash was found to be 95% effective in the treatment and control of bovine parasitic otitis after dipping clinically affected cattle twice weekly for twelve weeks. Only three of 64 clinically affected animals failed to recover completely following the above treatment regime. The viable nematodes, Rhabditis bovis, which were easily isolated from dip tanks prior to treatment, could no longer be isolated 48 hours following dip tank treatment with nicotine. The above results are very significant since the control of bovine parasitic otitis would greatly enhance the productivity of cattle.

The prevalence of taeniasis was determined during the period January to April 2013 in a cross-sectional study of non-descript domestic dogs from the livestock–wildlife ecosystem of Ngorongoro, Tanzania. Taeniid eggs were determined by screening faecal samples using the formalin-ether sedimentation technique. Predisposing factors for dog infection were assessed in relation to demographic, husbandry and management data. Of the 205 faecal samples screened, 150 (73.2%) were positive for taeniid eggs. The prevalence of dogs harbouring taeniid eggs was 80%, 30.2% and 75.3% in the less than 1 year, 1–3 years and greater than 3 years of age groups, respectively. Age group and sex prevalence in dogs did not differ significantly (P > 0.05), although the females showed a marginally higher prevalence (73.8%) in comparison to the males (72.7%). Taeniid eggs were significantly more likely to be found in the faeces of dogs located in Waso (80.6%) and Endulen (75%) than in Malambo (63.2%, P < 0.05). The study revealed that dogs owned and raised by agro-pastoralists were at a lower risk of acquiring Taenia spp. infection (P = 0.001) than those that were raised by pastoralists. The majority of dog owners were not aware of the predisposing factors and the mode of transmission of taeniids. Dogs were frequently fed on viscera, trimmings and the heads of slaughtered animals, and they were not treated for parasitic infections. The findings of this study indicate that taeniasis is prevalent among non-descript dogs in Ngorongoro, underscoring the need for further research and active surveillance to better understand the transmission cycle of Taenia spp. in a wider geographical area in Tanzania.