Escherichia coli O157 prevalene among cows in suburbs of HCMC

Abstract

To estimate the prevalence of E. coli O157 on suburb cow herds in Ho Chi Minh City, fecal samples were collected once from 6 randomly selected cow farms in the period March 2010 through April 2010. A total of 122 fecal samples from dairy and beef cows at stock farms in Vĩnh Lộc A commune - Bình Chánh district and Thủ Đức district of Ho Chi Minh City were collected. Samples were cultured for E. coli O157 in SMAC and MAC. The colorless colonies in SMAC (nonsorbitol fermenters) were selected from the plate of SMAC and first confirmed by agglutination with E. coli O157 antiserum coated latex test (Oxoid Ltd). The positive results from O157 testing were confirmed as E. coli by The API- 20E® kit (BioMerieux). Throughout three months of surveillance, a total of 48 O157-positive isolates were obtained from 122 samples of bovine feces. Of these 48 isolates, 47 isolates were biochemically identified as E.coli O157. The result showed the prevalence of O157 E. coli was 38.52%