Serological diversity, molecular characterisation and antimicrobial sensitivity of avian pathogenic Escherichia coli (APEC) isolates from broiler chickens in Kashmir, India
S. N. Magray A F , S. A. Wani B , Z. A. Kashoo B , M. A. Bhat C , S. Adil D , S. Farooq B , M. A. Rather A , Z. A. Kabli A , M. T. Banday D and Y. Nishikawa E
+ Author Affiliations
- Author Affiliations
A Disease Investigation Laboratory for Sheep and Goat, Department of Sheep Husbandry, Government of Jammu and Kashmir, Nowshera, Srinagar, 190011, India.
B Bacteriology Laboratory, Division of Veterinary Microbiology and Immunology, Faculty of Veterinary Sciences and Animal Husbandry, SKUAST-Kashmir, Shuhama, Srinagar, 190006, India.
C Division of Veterinary Microbiology and Immunology, Faculty of Veterinary Sciences and Animal Husbandry, R.S. Pora, SKUAST-Jammu, 181102, India.
D Division of Livestock Production and Management, Faculty of Veterinary Sciences and Animal Husbandry, SKUAST-Kashmir, Shuhama, Srinagar, 190006, India.
E Department of Food and Human Health Sciences, Graduate School of Human Life Science, Osaka City University, Osaka 558-8585, Japan.
F Corresponding author. Email: snmagraymicrobiol@gmail.com
Animal Production Science 59(2) 338-346 https://doi.org/10.1071/AN17065
Submitted: 4 February 2017 Accepted: 29 October 2017 Published: 8 January 2018
Abstract
The present study has determined the serological diversity, virulence-gene profile and in vitro antibiogram of avian pathogenic Escherichia coli (APEC) isolates from broiler chickens in India suspected to have died of colibacillosis. The virulence-gene profile of APEC was compared with that of the Escherichia coli isolates from faeces of apparently healthy chickens, called avian faecal E. coli (AFEC). In total, 90 representative isolates of APEC and 63 isolates of AFEC were investigated in the present study. The APEC were typed into 19 serogroups, while some isolates were rough and could not be typed. Most prevalent serogroup was O2 (24.44%). Among the eight virulence genes studied, the prevalence of seven genes (iss, iucD, tsh, cva/cvi, irp2, papC and vat) was significantly higher in APEC than in AFEC isolates. However, there was no significant difference between APEC and AFEC isolates for possession of astA gene. The most frequent gene detected among the two groups of organisms was iss, which was present in 98.88% and 44.44% of APEC and AFEC isolates respectively. The in vitro antibiogram showed that the majority (96.6%) of APEC isolates were resistant to tetracycline, while 82.2% were resistant to cephalexin, 78.8% to cotrimoxazole, 68.8% to streptomycin and 63.3% to ampicillin. However, most of them (84.45%) were sensitive to gentamicin. Thus, it is concluded that APEC from the broiler chickens carried putative virulence genes that attributed to their pathogenicity. Furthermore, the majority of APEC isolates were found to be multi-drug resistant, which, in addition to leading treatment failures in poultry, poses a public health threat.
Additional keywords: antibiogram, PCR, virulence genes.
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