Diversity in Biochemical Characteristics and Antibiotics Resistant Patterns Among Escherichia coli of Poultry Isolates

Abstract

A stronger association has earlier been reported between drug resistant human isolates of Escherichia coli and poultry isolates of E. coli than between drug-resistant and drug-susceptible human isolates of E. coli, in their phylogenic distribution, virulence and genotypes. It has been suggested that many of the drug-resistant human isolates were more likely to have originated in poultry (or a similar non-human reservoir). In this study, biochemical and antibiotic susceptibility tests were carried out on one hundred and fifty poultry isolates of Escherichia coli using Microscan® Dried Gram-negative Breakpoint Combo Pannels. The microscan panel analysed bacterial isolates for 24 biochemical tests and 23 to 25 antimicrobial agents following 16-20 hours of incubation at 35-37° C. Four different biotypes of E. coli were obtained. The biotypes showed variation in sucrose, adonitol, urea, H₂S, eusculin hydrolase, voges-proskeur, citrate and galactosidase tests. Resistance to antimicrobials varied from 5 to 21 of the 25 drugs tested. The carbapems (imipenem and meropenem) were very effective, while the isolates recorded very high resistance against ampicillin and tetracycline. There was variation in antibiotic resistant-patterns both within and across biotypes. Poultry industry may be contributing to the evolution of new biotypes and drug resistance among bacteria in Nigerian.

Keywords: Antibiotic resistance, Biochemical characteristics, Escherichia coli, Diversity, Poultry.