DETERMINATION OF ANTIMICROBIAL RESISTANCE AND CHARACTERIZATION OF ASSOCIATED GENES IN SALMONELLA AND Escherichia coli IN POULTRY AND ITS ENVIRONMENT
Loading...
Date
2022
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR
Abstract
A study was conducted to monitor the presence, antimicrobial resistance (AMR)
phenotype and genotype of Salmonella and E. coli in the entire commercial broiler supply
by collecting 232 samples from Broiler breeder farms (BBF), hatcheries, commercial
broiler farms (CBF) and retail meat shops (RMS). It was evident that enrichment in TTB
followed by colony PCR was rapid and specific; however, BGA and XLT4 were more
specific media for isolation of Salmonella. The overall presence of Salmonella and E.
coli in complete poultry supply chain was 20 and 72 per cent, respectively. A significant
higher (P<0.05) presence of Salmonella was observed in RMS (46%) followed by CBF
(19%), and hatcheries (10%). The presence of E. coli in BBF, hatcheries, CBF and RMS
were 48, 83, 70 and 91 per cent, respectively. Antimicrobial resistance based on disc
diffusion assay and MIC revealed that all the E. coli and Salmonella isolates were
resistant to at least one of the antibiotics and 75 & 76 per cent of the isolates were
multidrug resistant (MDR) respectively. In complete poultry supply chain E. coli and
Salmonella showed highest resistance to doxycycline (97 & 94%), followed by
fluoroquinolone, gentamicin, β lactam, sulphonamides and colistin and lesser resistance
to phenicols and neomycin. All E. coli and Salmonella isolates were screened for the
presence of 35 antimicrobial resistant (AMR) genes belonging to seven groups of
antibiotics by PCR and it was observed that the overall presence of AMR genes among
the E. coli and Salmonella isolates was 69 and 60 per cent respectively. Among the AMR
genes, highest presence was recorded for tetA (69%), followed by blaTEM, mcr2-5,
aac(6’)-Ib-cr, qnrS, qnrD, cmlA1, sul1, catA2, qnrB, blaCTX-M, blaSHV, mcr-1, catA1,
blaOXA and OqxAB in Salmonella and qnrB, qnrS, blaTEM, aac(6’)-Ib-cr, blaCTX-M, mcr1-5
(19.59%), qepA, mcr-4, cmlA1, sul1, catA1, blaSHV, catA2, qnrD, blaOXA and sul2, blaCTXM
group2, gropu9, &gropu8/25 in E. coli. There was fair to significant correlation
between AMR phenotype and genotype. AMR E. coli and Salmonella and genes
encoding AMR were present throughout the poultry supply chain, however CBF and
RMS were the major focal points of AMR. No significant difference in presence of AMR
E. coli could be observed during the crop cycles in CBF, as presence was observed at all
the intervals indicating the need for efficient monitoring and control strategies for
effective prevention of AMR in complete poultry supply chain.