Poultry play an important role in meeting the protein demand through the supply of chicken meat and eggs, and antimicrobial-resistant bacteria can be transmitted from poultry to humans through the food chain. In this study, 716 E. coli isolates were collected from poultry industry in Korea during the period from 2016-2018. Among the cephalosporin antimicrobial, the rate of resistance to first-cephalosporins (cefazolin and cephalexin) was more than 18.0% but secondcephalosporins (cefoxitin and cefuroxime) and four-cephalosporins (cefepime) was less than 10.0%, without any differences based on the poultry. In quinolone antimicrobial, the rate of resistance to nalidixic acid was more than 46.0% in all poultry but ciprofloxacin was more than 44.0% in broiler farm and chicken meat and less than 18.0% in layer farm and egg. In addition, the rate of resistance to ampicillin and tetracycline was more than 30.0% without any differences in poultry, but the rate of resistance to amoxicillin - clavulanate, trimethoprim - sulfamethoxazole, imipenem and gentamicin was higher in broiler farm and chicken meat than in layer farm and egg. MDR was detected in 120 (60.6%), 113 (79.6%), 80 (37.0%), and 75 (46.9%) isolates from broiler farm, chicken meat, layer farm, and egg, respectively, with an overall prevalence of 54.2% (388/716).

• Kwang Won Seo(College of Veterinary Medicine, Kyungpook National University)
• Young Ju Lee(College of Veterinary Medicine, Kyungpook National University) Corresponding Author