Fowl typhoid (FT) is a septicemic disease caused by Salmonella Gallinarum (S. Gallinarum) and is responsible for severe economic losses in Korea. In this study, 49 aminoglycosides (AMG)-resistant S. Gallinarum were analyzed to determine the phenotypic and genotypic characteristics. Thirty-six (73.5%) out of 49 AMG-resistant S. Gallinarum exhibited resistance to at least one agent in three or more of antimicrobial categories as multidrug-resistant (MDR) isolates. Among the AMG-resistant isolates exhibiting MDR, 21 (58.3%) and 11 (30.6%) of the isolates harbored ant(2")-I, which encodes an aminoglycoside adenylyltransferase, and blaTEM-1, which is a β-lactamase-encoding gene, respectively. The qnrB, cmlA, and sul1 and sul2 genes, which are related to resistance to quinolones, chloramphenicol and sulfonamides, respectively, were detected in 8.3~22.2% of the AMG-resistant isolates that exhibited MDR. Twenty-four (66.6%) of 36 AMG-resistance S. Gallinarum exhibiting MDR carried class 1 integrons with aadA genes cassettes. Several plasmid replicon types, such as B/O, FIIA, FIB, and Frep were considered to play a prominent role in S. Gallinarum, and the presence of these genetic characteristics remain a serious concern to the selection of antimicrobials for the treatment of FT.

• Jeom Joo Kim(College of Veterinary Medicine, Chungbuk National University)
• In Pil Mo(College of Veterinary Medicine, Chungbuk National University)
• Young Ju Lee(College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University) Corresponding Author.