Antibiotic-resistantSalmonella speciesandEscherichia coliin broiler chickens from farms, abattoirs and open markets in selected districts of Zambia

Abstract

30Salmonella species and Escherichia coli are major bacterial enteropathogens of global 31 public health importance that cause foodborne diseases, thereby contributing to increased 32 human morbidity and mortality. Both pathogens have also been found to contribute towards 33 the spread of antimicrobial resistance through the food chain, especially in poultry. The aim of 34 this study was to determine the occurrence of antibiotic-resistant Salmonella sp. and E. coli in 35 broiler chickens at farm level, abattoirs and open markets in selected districts of Zambia. A 36 cross-sectional study was undertaken in seven districts of Zambia to determine the resistance 37 profiles of Salmonella sp. and E. coli obtained from broiler chickens at farms, abattoirs and 38 open markets. A total of 470 samples were collected, including litter, cloacal swabs and carcass 39 swabs. Samples were inoculated into buffered peptone water, sub-cultured onto MacConkey 40 and Xylose Lysine Deoxycholate agar plates. Identification of Salmonella sp. and E. coli was 41 done using the API-20E kit and confirmation by 16S rDNA sequencing. Confirmed isolates 42 were tested against a panel of 10 antibiotics using the Kirby-Bauer disc-diffusion method and 43 interpreted according to the Clinical Laboratory Standards Institute guidelines. Analysis of the 44 antibiotic susceptibility test results was done using WHONET 2018 software. Overall, 4 45 Salmonella spp. and 280 E. coli were isolated. One of the Salmonella sp. was resistant to 46 ampicillin (25%), amoxicillin/clavulanic acid (25%) and cefotaxime (25%). E. coli antibiotic 47 resistance was highest to tetracycline (81.4%) and lowest to imipenem (0.7%). The antibiotic 48 susceptibility profile revealed 55% (154/280) multidrug resistant E. coli, with the highest 49 multidrug resistance profile (20.7%) in the ampicillin-tetracycline-50 trimethoprim/sulfamethoxazole drug combination. Furthermore, 4.3% (12/280) of the isolates 51 showed Extensive Drug resistance. The levels of antimicrobial resistance to E. coli and 52Salmonella observed in market-ready chickens is of public health concern.3 53

Antibiotic-resistant Salmonella species and Escherichia coli in broiler chickens from farms, abattoirs, and open markets in selected districts of Zambia

“…In this study, the highest multi-drug resistance (MDR) was observed to the following antibiotics ampicillin, tetracycline, and trimethoprim/sulfamethoxazole. These findings were in agreement with other studies done in Iran, USA, India, Brazil, Thailand, and Southern African, [1,16,36,[43][44][45] that revealed MDR in Enterobacteriaceae, including Salmonella spp. and E. coli.…”

“…This is similar to what was reported in India in which resistance was 18% amoxicillin-clavulanic acid, 18% ampicillin, 20% cefotaxime [36] and those reported in the United States in which they found the resistance of 1% amoxicillin-clavulanic acid, 26% ampicillin, and 0% Ceftriaxone. [16] The frequency and extent of Salmonella spp. resistance to antimicrobial drugs varies based on their usage in animal production and humans as well as on ecological differences in the epidemiology of Salmonella spp.…”

“…Carcass swabs were collected from under the wings of the chicken where the bacterial population is thought to concentrate during processing. [16]…”

Detection of Extended-Spectrum Beta-Lactamase (ESBL)-Producing Enterobacteriaceae from Diseased Broiler Chickens in Lusaka District, Zambia

“…The chicken population is estimated to be 94 million broilers, 15 million village chickens, and 5.8 million layers [1]. Moreover, poultry products in Zambia, like in other developing African countries, form an integral part of the human diet in many households, as they are cheaper source of animal protein and are easier to produce compared with other foods of animal origin [2,3].…”

Detection of Extended-Spectrum Beta-Lactamase (ESBL) Producing Enterobacteriaceae from Diseased Broiler Chickens in Lusaka District, Zambia

“…The chicken population is estimated at 94 million broilers,15 million village chickens, and 5.8 million layers [1]. Moreover, poultry products in Zambia, like in other developing African countries, form an integral part of the human diet in many households, as it is a cheaper source of animal protein and is easier to produce compared to other foods of animal origin [2,3].…”