Bacterial contamination of dead-in-shell embryos in ostrich hatcheries and antimicrobial resistance patterns of isolated Escherichia coli

Authors

1 Department of Avian Diseases, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran

2 Department of Clinical Sciences, Faculty of Veterinary Medicine, Islamic Azad University, Garmsar Branch, Garmsar, Iran

3 Department of Microbiology, Faculty of Veterinary Medicine, Islamic Azad University, Garmsar Branch, Garmsar, Iran

Abstract

BACKGROUND:The bacterial contamination of fertile eggs is
the most common cause of embryonic death in ostrich hatchery
units leading to financial loss in ostrich industry. OBJECTIVES:
The aim of this research was to investigate the bacterial
contamination status, with emphasis on Escherichia coli, of
ostrich hatcheries and the antimicrobial resistance profile of
isolated Escherichia coli. METHODS:Atotal of 120 ostrich eggs
with dead embryos, at weekly intervals, were collected from
three ostrich hatcheries. The dead embryos were sent to
laboratory and samples were collected aseptically from different
organs. Bacterial detection and identification were performed by
using standard bacteriological and biochemical techniques.
Antimicrobial susceptibility test was carried out by agar diskdiffusion
method against 27 antimicrobial agents. RESULTS:
Different types of bacteria were isolated from 56 eggs (46.7%).
Twenty-four ostrich eggs were shown to carry E. coli. In some
eggs, in addition to yolk sac, E. coli was also isolated from
meconium, liver, or heart blood which increased the total number
of E. coli isolates to 32. All E. coli isolates were susceptible to
trimethoprim + sulphamethoxazole, danofloxacin, and flumequine,
whereas all were resistant to carbenicillin and erythromycin.
Resistance to other agents was variable. Multi-drug
resistance pattern was found among all E. coli isolates and
included 2 to 12 drugs. Thirty-two E. coli isolates generated 30
different resistance profiles against 27 antimicrobial drugs.
CONCLUSIONS: This was the first comprehensive report
regarding the bacterial, particularly Escherichia coli, contamination
of dead-in-shell ostrich embryos and antimicrobial resistance
status of the Escherichia coli isolates from ostrich eggs in
Iran.

Keywords