Comparative occurrence of ESBL/AmpC beta-lactamase-producing Escherichia coli and Salmonella in contract farm and backyard broilers.

The present study was conducted to detect the occurrence of beta-lactamase and biofilm-producing Escherchia coli and Salmonella in apparently healthy broiler birds reared in household and contract poultry farms. In total, 150 cloacal swabs were collected from apparently healthy broiler birds of various age groups reared in backyard (n = 100) and contract farms (n = 50) in West Bengal (India). The isolation rate of ESBL producers was significantly more (P < 0·05) reared in contract poultry farms than those reared in backyard. Majority of the E. coli isolates possessed blaCTX-M followed by blaSHV and blaTEM . Majority of the Salmonella strains possessed blaTEM followed by blaCTX-M , and no blaSHV was detected. The selected sequences of the PCR products were found cognate with blaCTX-M-1 , blaCTX-M-2 , blaCTX-M-9 , blaCTX-M-14 , blaCTX-M-15 , blaSHV-12 and blaTEM-52 . The study detected 46·8% of E. coli and 42·5% of Salmonella strains as biofilm producers. Beta-lactamase-producing Enterobacteriaceae strains showed resistance against tetracycline, chloramphenicol, doxycycline, co-trimoxazole and ampicillin and sensitivity to imipenem-EDTA, colistin and gentamicin. The study revealed the partial clonal relationship of ESBL sequences possessed by the poultry isolates of the present study and local clinical isolates available in the database. The study made consumer awareness about careful handling of live birds or poultry meat to avoid the zoonotic transmission of antimicrobial-resistant Enterobacteriaceae.

Multi-drug resistant, biofilm-producing high-risk clonal lineage of Klebsiella in companion and household animals.

Antimicrobial resistance is a global emergency which needs one health approach to address. The present study was conducted to detect the prevalence of beta-lactamase and biofilm-producing Klebsiella strains in rectal swabs (n = 624) collected from healthy dogs, cats, sheep and goats reared as companion or household animals in India. The dogs and cats were frequently exposed to third- or fourth-generation cephalosporins for therapy. The sheep and goats were occasionally exposed to antibiotics and had environmental exposure. Phenotypical ESBL (n = 93) and ACBL (n = 88)-producing Klebsiella were isolated significantly more (P < 0·05) from companion animals than household animals. Majority of the Klebsiella possessed blaCTX-M-15 . The sequences blaCTX-M-15.2 , blaCTX-M-197 and blaCTX-M-225 are reported first time from the companion animals. All ACBL-producing isolates possessed blaAmpC . The present study detected 65·8% of Klebsiella strains as biofilm producers possessing the studied biofilm associated genes. The isolates showed phenotypical resistance against chloramphenicol, tetracycline, doxycycline, co-trimoxazole, ampicillin, cefotaxime/clavulanic acid. The present study showed that companion and household animals (dogs, cats, sheep, goats) may act as a carrier of ESBL/biofilm-producing, multi-drug resistant, high-risk clonal lineage of Klebsiella.

Characterization of beta-lactamase and biofilm producing Enterobacteriaceae isolated from organized and backyard farm ducks.

This study was undertaken to detect the occurrence of beta-lactamase and biofilm producing Enterobacteriaceae in healthy ducks. A total 202 cloacal swabs were collected from ducks kept in organized (n = 92) and backyard (n = 110) farms in West Bengal (India). The ducks had no history of antibiotic intake. Among the 87 phenotypically beta-lactamase producing Escherichia coli, 19 (17·43%), 6 (5·05%) and 15 (13·76%) isolates possessed blaTEM , blaSHV and blaCTX-M respectively. Whereas, 5 (38·46%) Salmonella isolates were found to harbour blaCTX-M . In K. pneumoniae 10 (33·33%), 3 (13·33%), 4 (13·33%) isolates possessed blaTEM , blaSHV and blaCTX-M respectively. The sequences of selected PCR products were found 98% cognate with blaCTX-M-9, blaSHV-12 and blaTEM-1 . Beta-lactamase producing E. coli isolates belonged to 14 different serogroups such as O1, O2, O3, O5, O7, O8, O35, O83, O84, O88, O119, O128, O145 and O157. Moreover, 87 E. coli (79·82%), six Samonella (46·15%) and 13 K. pneumoniae (43·33%) isolates were detected as AmpC producers possessing blaAmpC . Majority of E. coli (46·79%), Salmonella (46·15%) and K. pneumoniae (70%) isolates were detected as biofilm producers and possessed the associated genes (csgA, sdiA, rcsA, rpoS). Significantly higher occurrence of beta-lactamase and biofilm producing Enterobacteriaceae isolates was detected in backyard ducks than organized farms. SIGNIFICANCE AND IMPACT OF THE STUDY: Consumption of antibiotic through feed or during therapy is considered as potential reason for generation of antimicrobial resistant bacteria in birds. This study provides valuable evidence that exposure to contaminated environment may be an additional source for generation of antimicrobial resistant bacteria in backyard ducks. The backyard ducks are reared by marginal farmers in India who cannot offer antibiotics to them either through feed or during therapy due to high cost. The study also reveals a significant correlation between biofilm formation and possession of antimicrobial resistance genes in the bacterial isolates from the ducks.

Isolation, molecular characterization and antibiotic resistance of Shiga Toxin-Producing Escherichia coli (STEC) from buffalo in India.

In total, 363 Escherichia coli were isolated from 165 faecal samples of healthy buffaloes in West Bengal, India. Twenty-four of these isolates (6·61%) were found to carry at least one gene characteristic for Shiga toxin-producing Escherichia coli (STEC). These STEC strains belonged to 13 different O-serogroups. The stx1 gene was present in 23 (95·8%) of total STEC isolates, whereas 20 (83·3%) STEC isolates carried the gene stx2. Twelve strains of E. coli (50% of total STEC isolates) possessed enterohaemolysin (ehxA) gene in combination with others. Fourteen (58·33%) isolates found to possess saa gene. However, no E. coli was detected harbouring gene for intimin protein (eaeA). Of 23 stx1 -positive isolates, seven (30·43%) were positive for genes of the stx1C subtype. Of the 20 isolates with the stx2 gene, 25% (5/20) possessed stx2C and 10% (2/20) possessed stx2d gene. The phylogenetic analysis after RAPD of STEC strains revealed six major clusters. The isolated STEC strains were resistant most frequently to erythromycin (95·83%), cephalothin (62·5%), amikacin (54·17%), kanamycin (45·83%) and gentamicin (41·67%) group of antibiotics. No ESBL-producing (blaCTXM , blaTEM , blaSHV ) or quinolone resistance gene (qnrA) was detected in the STEC isolates.

Comparative possession of Shiga toxin, intimin, enterohaemolysin and major extended spectrum beta lactamase (ESBL) genes in Escherichia coli isolated from backyard and farmed poultry.

The present work was conducted to compare the occurrence of Escherichia coli possessing virulence and ESBL genes in backyard and farmed poultry. Three hundred and sixty samples from the poultry kept in backyard system and 120 samples from the farmed birds were collected from West Bengal, India. Among the E. coli isolates of backyard poultry (O2, O10, O25, O55, O60, O106, UT), none of them possessed any of the Shiga toxin genes and eight E. coli isolates (8/272; 2.9%) harboured eaeA gene alone. Whereas among the E. coli isolated from the farmed poultry (O17, O20, O22, O102, O114, O119, rough, UT), four isolates (4/78, 5.1%) harboured stx 1/stx 2 gene and 11 isolates (11/78, 14.1%) possessed eaeA gene. None of the E. coli isolates from the backyard poultry harboured any studied ESBL gene. Whereas 29.4% of E. coli isolates from the farmed poultry were found to possess the ESBL genes.