K-99~+ E. COLI FROM NEW-BORN CALVES

摘要

By picking up 4-6 colonies suggestive of E. coli faecal lample, 417 E. coli isolates from 105 diarrhoeic calves and 93 from 25 non-diarrhoeie calves were collected. Of these M. celi isolates, 88 could be serogrouped and were found to belong to 0129 (13.6%), 04 (12.5%), 076 (6.8%), 0123, 091 (5.6%), 0101, 0149, 0109, 061 (4.5%), 0138, 043, 045 (3.4%), 09 (1.1%) and untypable strains (10.2%). Of these 88 isolates grown in Minca media and Tryptic media, only 12 E. coli could show presence of K99 surfaceantigen on the basis of slide agglutination test. K99 antigencould not be detected in any of the 25 E. coli isolates recovered from non-diarrhoeal eases. Two salmonella stralns belonging to Sal, dublin were also isolated from diarrhoeic ealves.