Virulence Genes and Antimicrobial Resistance Profile of Escherichia Coli Isolates from Diarrhoeic Neonatal Dromedary Camels

Abstract

In the present study, Escherichia coli were isolated from rectal swabs of total 48 (20.68%) diarrhoeic neonatal dromedary camels during the five years study period in an organised farm. The PCR for amplification of virulence genes revealed that 31 (64.58%) isolates harboured at least one virulence gene. The detection rates of stx1, stx2, eae, F41, K99 and sta virulence genes were 4.16%, 2.08%, 35.41%, 14.58%, 18.75% and 16.66%, respectively. Based on occurrence of these virulence genes the isolates were pathotyped into shigatoxigenic E. coli (STEC) (6.25%), enteropathogenic E. coli (EPEC) (20.83%) and enterotoxigenic E. coli (ETEC) (29.16%). Atypical combinations of EPEC+ETEC (8.33%) were also detected. The E. coli isolates from all three neonatal camels having acute haemorrhagic enteritis and mortality were found to be of STEC type. In antibiotic sensitivity test, most prevalent resistance was observed against amoxicillin, cloxacillin, erythromycin and lincomycin whereas lowest resistance was observed against gentamicin and amikacin. Findings of this study indicate that neonatal camels are the probable reservoir of multidrug resistant and zoonotic STEC. Young age (below 7 days), housing system with loose sandy ground and winter season were identified as important risk factors for high incidence of neonatal camel calf diarrhoea in the present study.