Prevalence, molecular fingerprinting and drug resistance profile of enterovirulent Escherichia coli isolates from free-ranging yaks of Tawang district, Arunachal Pradesh, India.
Of 273 samples (rectal swab) collected from free-ranging yaks of Tawang district, Arunachal Pradesh, 42 Shiga toxin-producing Escherichia coli (STEC), six enteropathogenic E. coli (EPEC) and 27 enterotoxigenic E. coli (ETEC) strains were isolated. All the STEC and EPEC strains were further investigated for respective stx variants (for STEC only) and additional putative virulence factors. The 27 ETEC strains were also screened for characteristic enterotoxin gene(s) and colonization factors. Occurrence of ETEC was significantly (p < 0.05) higher in the diarrheic yaks and yaks of less than 1 year of age. Majority of enterovirulent E. coli isolates were resistant to amikacin, azithromycin, chloramphenicol, colistin, doxycycline, furazolidone, nalidixic acid, nitrofurantoin, streptomycin and tetracycline. Dendrogram, constructed with molecular fingerprinting profiles obtained from RAPD (Randomly Amplified Polymorphic DNA) and ERIC (Enterobacterial Repetitive Intergenic Consensus) PCR, placed the isolates in different clusters irrespective of their serotypes, virulence gene and drug resistance pattern. Collectively, the study indicates that yaks, being a potential reservoir of multidrug resistant STEC and EPEC, may represent significant risk to public health in this region. Higher recovery of ETEC isolates from yaks with diarrhea points out that ETEC may be a major determinant for repeated occurrence of diarrhea in yaks.
National Research Centre on Yak, ICAR, Dirang, 790101 West Kameng, Arunachal Pradesh, India. samiranvet@gmail.com
Samiran
S
Bandyopadhyay
Chandan
C
Lodh
Mihir
M
Sarkar
Monoj K
MK
Ghosh
Asit K
AK
Bera
Debasish
D
Bhattacharyya
Dipak K
DK
Mondal
Kishore K
KK
Baruah
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology; D016172:DNA Fingerprinting / Q000662:veterinary; D004269:DNA, Bacterial / Q000235:genetics; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D024901:Drug Resistance, Multiple, Bacterial; D054308:Enteropathogenic Escherichia coli / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D054307:Enterotoxigenic Escherichia coli / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D007194:India; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D015995:Prevalence; D019105:Random Amplified Polymorphic DNA Technique / Q000662:veterinary; D017422:Sequence Analysis, DNA / Q000662:veterinary; D054323:Shiga-Toxigenic Escherichia coli / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D037521:Virulence Factors / Q000235:genetics / Q000302:isolation & purification
D004269:DNA, Bacterial; D037521:Virulence Factors