Biochemical and serological characterization of <i>Escherichia coli</i> isolated from colibacillosis and dead-in-shell embryos in poultry in Zaria, Nigeria

Abstract

This study was designed to determine the isolation rate, serotypes and biochemical profiles of E. coli from colibacillosis and dead-in-shell embryos in Zaria, Northern-Nigeria. The isolation rate of E. coli from hatcheries studied were 4.67% and 7.50% from farms of Simtu Agricultural Company and National Animal Production Research Institute (NAPRI) Shika Zaria, Nigeria respectively. Twenty E. coli isolates from clinical cases of colibacillosis were also used for this study. The Simtu farm E. coli isolates showed 97.5% motility, while isolates from both NAPRI and clinical colibacillosis cases were 100% motile. The results of carbohydrate fermentation were variable without any specific pattern, except for few sugars that had 100% fermentation especially the lactose, ducitol, rhamnose, and xylose of E. coli isolates from clinical cases of colibacillosis. The major serotypes recorded from clinical cases of colibaccillosis were O8:K50 and O9:K30. Serotypes obtained from the dead-in-shell embryos were O78:K80, O8:K50, O9:K30, and O26:K60. Untypable isolates made up the greater percentage of E. coli strains studied. The antibiotic susceptibility testing showed that most of the isolates were resistant to more than one antibiotic. Majority of the isolates were sensitive to ciprofloxacin (85%) of the clinical cases and 100% of each of the Simtu and the NAPRI. farms. In conclusion, this study has revealed the involvement of several E. coli serotypes in colibaccillosis and dead-in-shell embryos. It is recommended that measures aimed at reducing the emergence of resistant strains of E. coli be instituted in all the farms.

Keywords: Escherichia coli, Serotypes, biochemical profiles, and dead-in-shell embryos

Nigerian Veterinary Journal Vol. 27 (2) 2006: pp. 33-40