Prevalence and antimicrobial resistance in Campylobacter from different stages of the chicken meat supply chain in Morogoro, Tanzania

Abstract

Poultry are recognized as a main reservoir of Campylobacter spp. However, longitudinal studies investigating the persistence of Campylobacter on broilers and retail chciekn meat in Tanzania are rare. The aim of the current work was to evaluate the prevalence and antimicrobial susceptibility of Campylobacter spp. isolated from broiler farms and retail chicken meat. Eight hundred samples were collected from broilers aged 1 week to slaughter and retail chicken carcasses, consisting of 600 fecal droppings and 200 carcass rinses. The overall Campylobacter prevalence was 43.3% (381/880). The isolation rate of Campylobacter from chicken faeces was 41.5%, from carcasses at the farm was 51.0% and from carcasses from retail stores was 37.5%. Biochemical testing by hippurate hydrolysis identified 72.4% of all isolates as C. jejuni, 20.5% as C. coli, and 7.1% as other Campylobacter spp. Multiplex polymerase chain reaction confirmed 75.1% of all isolates as C. jejuni, 17.8% as C. coli, 4.2% as both, and 2.9% as other Campylobacter spp. Antimicrobial susceptibility testing using disk diffusion assay and broth micro-dilution method revealed resistance to: ampicillin (41% and 44%, respectively), ciprofloxacin (56 and 59%), erythromycin (17 and 18%), gentamicin (6% and 12%), streptomycin (20 and 23%), and tetracycline (62 and 63%). Resistance to azithromycin (9%), chloramphenicol (7%) and nalidixic acid (72%) was determined using the disk diffusion assay only. Up to 5% and 4% of all isolate tested were pan-susceptible, while, 67% and 40% showed multidrug resistance using the disk diffusion assay and the broth microdilution method, respectively. These results reinforce the need of efficient strategy implementation to control and reduce Campylobacter in chickens at production and slaughter levels, and the necessity to reduce the use of antimicrobials in poultry sector.

Keywords: Campylobacter, poultry and poultry meat, Isolation rate, antimicrobial resistance