Class 1 integrons and Salmonella genomic island 1 among Salmonella enterica isolated from poultry and swine.
Two hundred eleven Salmonella enterica strains representing 35 serotypes isolated from healthy poultry (n=103) and swine (n=108) were used in this study. The occurrence and characteristics of class 1 integrons were investigated. Salmonella genomic islands (SGIs) and the horizontal transfer of integrons were assessed. One hundred eighty-six isolates (88%) were resistant to at least one antimicrobial and 140 isolates (66%) were multidrug resistant. The intI1 gene was present in 54 isolates (25.6%), of which 33 (15.6%) carried gene cassettes with sizes ranging from 0.7 to 2.3 kb. Sequence analysis revealed 11 distinct integron profiles in which resistance genes bla(PSE-1), dfrA1, dfrA12, aadA2, aadA4a, and silB were present. The gene cassette array dfrA12-aadA2 was the most prevalent among the isolates whereas most integrons were located on conjugative plasmids. SGI1 variants (SGI1-A and -F) were present in nine isolates belonging to serovars Albany, Emek, Kedougou, and Kingston.
Khemtong
Sirintip
S
Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.
Chuanchuen
Rungtip
R
D000822:Animal Husbandry; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D044404:Genomic Islands; D032023:Integrons; D011200:Poultry / Q000382:microbiology*; D019779:Salmonella enterica / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D013552:Swine / Q000382:microbiology*
D000900:Anti-Bacterial Agents