Bacteria resistance to antibiotics has become a worldwide problem impacted partly by antibiotics use in livestock production. The present study investigated the pattern and mechanisms of resistance in 21 bacteria species isolated from a river used as a waste-dump by a poultry farm in Ogbomoso, southwestern Nigeria. | O. O. ADELOWO, O. E. FAGADE Turk J Biol 36 (2012) 37-45 © TÜBİTAK doi: Phylogenetic characterization, antimicrobial susceptibilities, and mechanisms of resistance in bacteria isolates from a poultry waste-polluted river, southwestern Nigeria Olawale Olufemi ADELOWO1, Obasola Ezekiel FAGADE2 1 Department of Pure and Applied Biology, Ladoke Akintola University of Technology, PMB 4000, Ogbomoso - NIGERIA 2 Environmental Microbiology and Biotechnology Laboratory, Department of Botany and Microbiology, University of Ibadan, Ibadan - NIGERIA Received: Abstract: Bacteria resistance to antibiotics has become a worldwide problem impacted partly by antibiotics use in livestock production. The present study investigated the pattern and mechanisms of resistance in 21 bacteria species isolated from a river used as a waste-dump by a poultry farm in Ogbomoso, southwestern Nigeria. Bacteria were isolated on nutrient agar supplemented with 50 μg/mL of tetracycline, their identities were determined by PCR amplification, and sequencing of their 16s rRNA genes and their susceptibility to 6 antimicrobials determined by broth dilution. The molecular basis of resistance among the isolates was also investigated by the PCR amplification of class 1 and 2 integrons, tetA, tetB, tetC, tetD, tetE, tetG, tetL, tetW, tetM, tet37, blaTEM, aadA1, strA, strB, sul2, sul3 and a 550bp gene fragment encoding a multidrug resistance efflux transporter of the resistance nodulation division (RND) family. All the isolates were resistant to the tested antimicrobials with MIC ranging from 512 256 >512 >256 ND Brev. diminuta XW2a 16 512 256 >512 >128 HAE1 B. cereus XW2b 512 512 >256 ND C. cellulans XW31 >64 32 128 256 >512 64 ND Alc. faecalis XW5 32 512 256 ND St. maltophilia XW61 512 >256 >512 512 HAE1 R. ornithinolytica XW721 128 256 >512 256 >512 >256 HAE1 C. freundii XW722 128 512 512 64 16 512 256 >512 >256 No .
