The use of spleen antigen in the tube agglutination test for diagnosis of anaplasmosis in cattle.

An antigen was prepared from the spleen of an infected bovine calf and was used in the tube agglutination test. Cases having rare and very low parasitaemia as well as the carrier cases were detected by this procedure and no non-specific reaction was observed with other haemoprotozoan infections. The maximum titre obtained with the Anplasma positive sera was 1:20, about 60 per cent showed a titre of 1:10 and 90 per cent showed a titre of 1:5 or more. The test provided satisfactory results in detecting the cases even at the early phase of the infection. The test also proved useful in judging the efficacy of a drug employed to destroy the carrier status.