Antimicrobial resistant coliforms across four poultry production systems in Arusha and Moshi, Tanzania

Abstract

Introduction: resistance to antimicrobials poses a threat to human and animal health. This study aimed to determine the prevalence of resistant coliforms in poultry cloacal samples collected from different poultry systems in Arusha and Moshi districts, Tanzania. Methods: ten administrative wards were randomly chosen in Moshi and Arusha urban districts, with a random selection of one representative farm in each ward per production system (extensive, semi-intensive, intensive, and broiler systems). Per farm, 10 chickens were sampled using cloacal swabs. Samples were tested for the presence of coliforms using MacConkey agar without or with tetracycline, ciprofloxacin, ceftazidime, and Imipenem. R software was used for data analysis. Results: of the 80 farms targeted, samples were collected from 79 farms representing a total of 746 samples, of which 648 (86.8%) had coliforms corresponding to 74 of the 79 sampled farms. There was no significant difference in the overall prevalence of coliforms between Moshi (86%) and Arusha districts (87%) (p=0.81). The overall proportions of resistant coliforms in Arusha and Moshi varied depending on each antimicrobial type. The prevalence of coliforms resistant to tetracycline (95%) across all farm types in both districts was higher compared to ciprofloxacin (72%), imipenem (71%), and ceftazidime (84%) (p<0.0001). The median counts of coliform resistance (in log cfu) ranged from 4 to 10, with no significant distinctions between antimicrobial types. Conclusion: there is a widespread presence of antimicrobial resistant coliforms in poultry production systems. High tetracycline resistance was observed across all farm types in both districts.