Lesions and Bacteriological Findings in Colibacillosis of Calves

Abstract

SUMMARY This paper records the gross lesions and the histological and bacteriological findings in a series of 25 calves, of which some died from colibacillosis and others were killed either in extremis or immediately after diarrhoea was first observed. The results of an experiment to determine the effects of post-mortem autolysis on the interpretation of the pathological findings are also recorded. The lesions included pulmonary oedema, oedema in the abomasum and enteritis which varied in its severity and distribution. The E. coli strains isolated from the majority of the calves were identified as serotypes 015 : K?, 026 : K60(B), 035 : K? and 078 : K80(B) but some calves yielded strains which failed to type. Nine of the calves were septicaemic and in six the E. coli were confined to the intestine. In the remainder, E. coli were isolated from the intestine and some other organs, principally the spleen. These findings are discussed in relation to the role of endotoxin in the pathogenesis of colibacillosis.