Abstract: The purpose of the current study was to compare different serological test for diagnosis of brucellosis in vaccinated sheep. A total of 40 sheep that belonged to a governmental farm at El-Badary city, Assiut Governorate, Egypt were subjected to study during the period from May 2009 to January, 2010. Sheep (8-12 months old) that proved free from brucella infection were vaccinated and included in the study. A total of 190 blood serum samples were aseptically collected from animals under investigation before vaccination and at days 30, 90, 150 and 240 post-vaccination. Generally the number of positive reactors after vaccination where higher by using Buffered Acidified Plate Antigen Test (BAPA), Rose Bengal Plate Test (RBPT) and Rivanol Test (Riv. T) than Competitive Enzyme Linked Immunosorbent Assay (cELISA). The number of positive reactors was 12, 10, 16 and 16 at 30, 90, 150 and 240 days, respectively by using BAPA, RBPT and Riv. T. On the other hand, the numbers of positive reactors were 7, 3, 13 and 13 at 30, 90, 150 and 240 days, respectively by using cELISA. It could be concluded that differentiation between naturally infected sheep with brucellosis and vaccinated ones still acts as a major problem in sheep herds at 1st month post vaccination. Conventional tests cannot differentiate between vaccinated and infected sheep. The cELISA test gives accurate results at 90 days or more post vaccination.
Al-Hassan M. Mustafa, Mahmoud R. Abd Ellah, Essam El-Din M. Elbauomy and Ali H. Sadiek, 2012. Comparative Studies of Different Serological Tests for Diagnosis of Brucellosis in Vaccinated Sheep with Special Reference to Competitive ELISA. Veterinary Research, 5: 31-36.