Cross-Sectional Study for Detection and Risk Factor Analysis of ESBL-Producing Avian Pathogenic Escherichia coli Associated with Backyard Chickens in Pakistan.

The increasing incidence of extended-spectrum β-lactamase (ESBL)-producing (.) in backyard chicken farming in Pakistan is of serious concern. This study aimed to assess the prevalence, antimicrobial resistance patterns and risk factors associated with ESBL avian pathogenic (APEC) isolated from backyard chickens in the Jhang district, Punjab, Pakistan. In total, 320 cloacal swabs were collected from four breeds of backyard chicken (Aseel, Golden, Misri and Necked Neck). ESBL were phenotypically identified using double disc synergy test (DDST) and corresponding genes were confirmed by multiplex polymerase chain reaction (mPCR). Out of the 320 samples, 164 (51.3%) were confirmed as while 74 (45.1%) were characterized as ESBL . The frequency of isolation of ESBL was highest in Aseel chickens (35.1%). Of the 164 confirmed , 95.1%, 78.6%, 76.8%, 71.3%, 70.1%, 68.9%, 60.4% and 57.3% were resistant against tylosin, doxycycline, cefotaxime, enrofloxacin, colistin, trimethoprim/sulfamethoxazole, chloramphenicol and gentamicin, respectively. The ESBL gene types detected and their corresponding proportions were (54.1 %, 40/74), , (12.2%, 9/74) and co-existence ( and ) were shown in 33.8% (25/74). The gene sequence showed homology to from clinical isolates. The mean multiple antibiotic resistance index (MARI) was found to be higher among ESBL (0.25) when compared to non-ESBL (0.17). Both free-range husbandry management system ( = 0.02, OR: 30.00, 95% CI = 1.47-611.79) and high antimicrobial usage in the last 6 months ( = 0.01, OR: 25.17, 95% CI = 1.81-348.71) were found significantly associated with isolation of ESBL-producing in the tested samples using binary logistic regression analysis. This study confirmed the potential of backyard chickens as a reservoir for ESBL in the Jhang district, Punjab, Pakistan.