Prevalence of antibodies to Brucella spp. in cattle, sheep, goats, horses and camels in the State of Eritrea; influence of husbandry systems.

Samples from 2427 cattle, 661 goats, 104 sheep, 98 camels and 82 horses were screened for brucella infections by the Rose Bengal Test and positive reactors confirmed by the complement fixation test. In cattle, the highest individual seroprevalence was in dairy herds kept under the intensive husbandry system, with an individual prevalence of 8.2% and unit (herd) seroprevalence of 35.9%. This was followed by the pastoral husbandry system in the Western Lowlands with 5.0% individual but a higher unit (vaccination site) prevalence of 46.1%. The lowest was in the mixed crop-livestock system in the Southern Highlands with individual 0.3% and unit (village) prevalence of 2.4%. In sheep and goats, no positive animals were detected in the mixed crop-livestock areas. In the Eastern Lowlands individual prevalences of 3.8% (goats) and 1.4% (sheep) and unit prevalence of 33.3% (goats) and 16.7% were found, while 14.3% of individual goats and 56.3% of the units in the Western Lowlands were positive. No positive horses were found. The present study documents the first serological evidence of Brucella spp. infection in camels (3.1%) in Eritrea.