Seroprevalence of brucellosis in domestic ruminants in livestock-wildlife interface: A case study of Ngorongoro Conservation Area, Arusha, Tanzania

Abstract

A limited study was conducted to determine prevalence of brucellosis in domestic ruminants kept in a free range grazing system in Ngorongoro Conservation Area (NCA) which is a world heritage site in which pastoralists communities have been living harmoniously with wildlife for decades. Blood samples from 200 cattle, 87 goats and 13 sheep were collected by venipuncture into plain vacutainer tubes. Rose Bengal Plate Test (RBPT) and Microagglutination Test were used to detect antibodies against brucellosis in sera obtained from sampled blood. It was observed that 14.28% adult cows, 7.54% heifers, 2.38% bulls, 11.9 does, 10.7% bucks, and 10% ewes showed positive reactions to RBPT. When same samples were tested with MAT, 10.05% adult cows, 7.54% heifers, 2.38% bulls, 13.8% does, 14.3% bucks, and 3% ewes tested positive. Based on these serological tests it was concluded that brucellosis is endemic in pastoral livestock in NCA and that the reported increase in human brucellosis among pastoralists living in the NCA might be associated with domestic ruminants which are the sole source of food and income for the pastoralist in the area. Wildlife-domestic animals interaction phenomenon in NCA can as well be viewed as a significant means with which zoonoses are maintained in such ecosystem.

Key words: Prevalence, brucellosis, livestock-wildlife interface, other zoonoses