A serological investigation was carried out in some ruminant species including cattle (100), sheep (200) and goats (200) in Alexandria Province. Serum samples were randomly selected then tested for the presence of antibodies against Brucella by using the Rose Bengal test (RBT) supplied by Veterinary Vaccine Institute, Abbasia, Egypt and only positive samples were confirmed by Complement Fixation test (CFT). It was found that the seroprevalence of Brucella antibodies in the examined serum samples of cattle, sheep and goats was 6, 6 and 7 %, respectively. The effect of some epidemiological factors including seasons of the year and sex groups on the occurrence of infection in ruminant animals were studied. The obtained results clarified that occurrence of Brucella infection was higher in females than in males with highest seasonal incidence occurring in spring season. Our study revealed that brucellosis is endemic at high levels in all ruminant species in the study area and questions the efficacy of the control measures in that place. The high intensity of infection transmission among ruminants combined with high livestock and human density and widespread marketing of unpasteurized milk and dairy products may explain the increasing rates of human brucellosis. The public health importance of brucellosis was discussed and an effective integrated human-animal control strategy is urgently needed.
Key words: Brucella, ruminant, Serology