Prevalence of eaeA and qacEΔ1 genes in Escherichia coli isolated from omphalitis in baby chicks

Document Type : Original Article

Authors

1 Bacteriology, Immunology and Mycology Department, Faculty of Veterinary Medicine, Benha University

2 Animal Health Research Institute, Dokki Lab., Giza

3 Animal Health Research Institute, Dakahlia branch

Abstract

A total of two hundred diseased Saso chicks with omphalitis were examined (1400 samples) for the isolation of E. coli
from different organs (liver, caecum, spleen, heart, lung, yolk sac and cloacal swab). Results showed that 64 cases were
positive with an incidence of 32%. Fifty isolates (25%) of E. coli were recovered from chicks could be sero-grouped in
19 O groups with the most predominant serotype was O91 20 % (10 out of 50 isolates), O26 10% (5 strains out of 50) O78
8% (4 strains out of 50), and 7 strains untypable E. coli 14%. Among E. Coli O groups were found to be resistant to
Amoxicillin 93.02% followed by Tetracycline 74.42%, Enrofloxacin 46.51%, Erythromycin 30.32%, Ciprofloxacin
27.91%, Norofloxacin and Streptomycin 20.93% and Gentamycin 6.98%. While they were found to be sensitive for
Gentamycin, Streptomycin, Ciprofloxacin, Tetracycline, Erythromycin, Norofloxacin, Enrofloxacin, and Amoxicillin as
the following: 88.37%, 46. 51%, 34.89%, 23.26%, 18.60%, 9.30%, 9.30% and 6.98%, respectively. The incidence rate
of eaeA gene of E. coli was 15.79%. Quaternnary ammonium compound (qacEΔ1) gene also was detected in E. coli with
incidence rate 63.16%.

Keywords