Seroprevalence of bluetongue in sheep and goats in Kerala

Abstract

A study was conducted to assess the seroprevalence of BT in sheep and goats in Kerala, employing AGID, T-ELISA and dot-ELTSA tests. A total of 1010 samples collected from all the 14 districts of the State were screened for the presence of group specific antibodies to BTV. Seropositive samples were obtained from 12 out of the 14 districts. Both sheep and goats were found to harbour antibodies to BTY. Based on the results of the 1- ELISA test, the highest prevalence was observed in Thrissur district (21.10 per cent) and the lowest in Ernakulam district (1.25 per cent). Higher prevalence rates were observed in organized farms. The overall prevalence of the disease in the state was found to be 7.82 per cent. Of the tests employed, AGID test was found to be the least sensitive: The maximum number of positive samples were detected by I-ELISA. To check the validity of the I-ELISA results C-I~:LISA was done and there was good correlation between the results of the two tests as only four samples were detected as false positive in the C-ELISA. Dot-ELISA was found to be a simple, quick and specific test with detection levels comparable to T-ELlSA and could be used in the field conditions. Screening of the cattle population also should be done to get a better picture of the disease in the State as they comprise the largest reservoir of BTV in nature.