Prof. Bekele MegerssaMisrak Netsere2023-12-092023-12-092023http://etd.aau.edu.et/handle/123456789/526Broiler meat is a popular animal source food that can pose risks to human health as it may be contaminated with harmful microorganisms and antimicrobial residues. Investigations of those risks of broiler meat are limited in the study area. Thus, a cross-sectional study was carried out on selected Bishoftu farms, from January to July 2022, to investigate the microbial load, to isolate and identify selected bacterial pathogens and their antimicrobial resistance profile as well as detection and quantification of antibiotic residues of backyard broilers meat. A one hundred twenty broiler carcass samples were randomly collected and analyzed using TEMPO® for enumeration of microbial load, 3MTM Molecule for detection of Campylobacter, BIOLOG® for E. coli O157:H7 and Salmonella isolation and identification. The VITEK 2XL was used for antimicrobial resistance profiling, whereas a High-Performance Liquid chromatograph coupled with a triple quadrupole mass spectrometer (HPLC-ESI-MS/MS) was used for the detection and quantification of antibiotic residues. This study has revealed, 120 (100%) E. coli and total aerobic bacteria, 114 (95 %) coliform, and 105 (87.5%) S. aureus contaminations found in the samples were above the limit of Ethiopian standard requirements. In all the farms at least one bacteria pathogen was detected with an overall ratio of Campylobacter 75 (62.5%), E. coli O157:H7 27 (22.5%) and Salmonella 20 (16.7%). Of the isolates of E. coli O157:H7 and Salmonella, 11 (40.7%) and 13 (65%) were multi-drug resistant with three extensively drug resistance (XDR) and one pan drug resistance (PDR) Salmonella isolates respectively. Regarding antibiotic residues, 4 (3.3%), 22 (18.3%), and 30 (25%) of the samples analyzed contained detectable levels of residues of sulfadiazine, oxytetracycline and enrofloxacin respectively, while none was detected with tetracycline residue. Among these, 26 (21.67%) and 1(0.8%) of the samples respectively had oxytetracycline and enrofloxacin residues above the EU Maximum Residue Limits. These indications of high pathogenic bacteria contamination and antibiotic residues with multi-drug resistance on broiler meats might be due to unregulated slaughter facilities and irrational veterinary antibiotic uses. To mitigate the health risks of consumers, the establishment of standard slaughterhouses, applications of food safety procedures and raising awareness in rational use of drugs for broiler meat producers are vital.enAntibiotic residuesAntibiotic resistancesBacteria countCampylobacterEscherichia coli O157:H7 and SalmonellaThesis