Abstract:

Escherichia coli are zoonotic bacteria important to both public health and veterinary medicine. This study was carried out to identify the different diarrheal E. coli pathotypes and determine their resistance to selected antibiotic drugs in comparison to the non-pathotypes. A total of 288 faecal samples were collected from cattle and chickens. 24 STEC and four EPEC were detected in cattle and chicken faeces respectively. The 24 STEC either carried only six/ (8 %), stX2 (37.5 %), or both six/ and stX2 (42 %), stX2 and eaeA (12.5 %) genes. Ten (41.7%) STEC were antibiotic resistant as follows: ciprofloxacin (12.5%), chloramphenicol (8.3%), nalidixic acid (8.3%) and tetracycline (33.3%). Of the four EPEC, only two were resistant, one to ciprofloxacin and the other to tetracycline. Comparison of antimicrobial resistance (AMR) between E. coli pathotypes and non-pathotypes showed that non-pathotypes were more resistant (79.8%) than the pathotypes (42.9%). In conclusion, the fact that only EPEC was identified in healthy chickens and STEC in healthy cattle suggest presence of host preference factors for these pathotypes. Presence of such virulent pathotypes indicates a potential threat in the human food chain. Antibiotic resistant pathotypes were observed suggesting that healthy cattle & chicken faeces present a high risk of spreading antimicrobial resistant pathogenic E. coli to man, as well as indicating improper use of antimicrobial drugs. 1 therefore recommend that; monitoring of hygiene in slaughter places and dairy processing plants, and continued surveillance of emerging AMR among the pathogenic strains especially in the healthy animals be carried out. Studies should be carried out to establish the relationship between pathotype carriage and host preference, and the distribution of antibiotic resistance genes among E. coli pathotypes of chickens, cattle and humans.