Prevalence of Brucella antibodies in sheep and springbok (Antidorcas marsupialis) reared together in the Karas region, Namibia

Abstract

An outbreak of brucellosis in sheep in 2009 on a farm in the adjacent Hardap Region of Namibia and the lack of information on the brucellosis status of springbok prompted a serological investigation of brucellosis in sheep and springbok in the Karas Region, Namibia as these two species are utilized for meat. The main aim of the study was to find out if springbok reared with sheep are infected with brucellosis. Sera collected from sexually mature naïve sheep (n=332) and from springbok (n=345) on 11 randomly selected commercial farms and from adult sheep (n=472) and springbok (n=9) on eight commercial farms identified as positive for Brucella melitensis between 2008 and 2010 tested negative for Brucella antibodies. However, 10% (95% CI: 2.78-26.0) of the tested sheep on one farm tested positive for B. ovis antibodies confirming the presence of this agent in the region. On the eight exposed farms, both sheep and springbok tested negative for Brucella antibodies, providing evidence that control measures that were implemented following the detection of the disease had been effective. It was concluded that sheep and springbok on the eleven farms had not been exposed to Brucella melitensis and B. abortus infections and that on previously positive farms the infection had been eliminated in sheep and had not spread to springbok.

Key words: springbok, sheep, Brucella melitensis, Brucella abortus, Brucella ovis, Namibia