Experimental infections with coccidiosis and serum antibody quantitation in two breeds of goats

Abstract

Two goat breeds, Anglonubian and Saanen were obtained at an early age and reared coccidia-free until they were 1 month old. They were then infected with 200,000 sporulated oocysts comprising mainly Eimeria christenseni (49%), E. apsheronica (29%) and lesser proportions of E. arloingi, E. hirci, E. ninakohlyakimovae and E. alijevi. Following patency, the number of faecal oocysts per gram were determined for each animal and body weights taken weekly. An ELISA was developed to assay antibody titres in pre- and post-infection sera of each individual kid. Cleaned unsporulated oocysts were sonified and the resulting soluble antigen used. Anglonubians shed significantly more oocysts daily (P less than 0.01) and also suffered greater retardation in growth. Initially both breeds had very similar growth rates, however post-infection weekly body weight gain among the Anglonubians was on average 1100 g compared to 1300 g for the Saanens. Antibody titres post-infection increased significantly among the Saanens (P less than 0.01) and also all but one among the Anglonubians recorded an increase in antibody titres. Unsuckled kid serum was devoid of any antibody activity.