Heterologous Versus Homologous Antigens in the Serological Diagnosis of Small Ruminant Brucellosis

C.M.Roushdy1, A.M.Selim2, F.K..Hamouda2, E.M.El-bauomy1"


To elucidate controversial issue about variances between heterologous (B. abortus) and its counterpart homologous (B. melitensis) antigens used in serological examination of brucellosis in sheep and goats, sera of 250 sheep and 160 goats from seven Egyptian governorates were examined using both antigens in microplate serum agglutination (MAT) and complement fixation tests (CFT). The usefulness of melitensis antigen for diagnosis of small ruminant brucellosis was evaluated using a panel of selected immunoassays (BAPA, modified RB 8%, RB 3%, MAT and CFT with both abortus and melitensis antigens). The diagnostic sensitivity (D-se) and diagnostic specificity (D-sp) of such immunoassays were estimated. The significance and interaction of animal species, test categories as factors affecting results were assessed and results discussed. Kappa agreement between both antigens was substantial. No significant differences (p > 0.05) between groups of sheep and goats in MAT were found. Contrariwise, CFT showed significant difference (p < 0.05) between different groups of sheep and goats except between (sheep CFT melitensis and goat CFT abortus).

Key words

Heterologous B.abortus antigen, Homologous B. melitensis antigen, CFT, MAT, Small ruminants.