title: Identification and prevalence of tetracycline resistance in enterococci isolated from poultry in Ilishan, Ogun State, Nigeria.
abstract: BACKGROUND
  Tetracycline is one of the most frequently used antibiotics in Nigeria both for human and animal infections because of its cheapness and ready availability. The use of tetracycline in animal husbandry could lead to horizontal transfer of tet genes from poultry to human through the gut microbiota, especially enterococci. Therefore, this study is designed to identify different enterococcal species from poultry feces in selected farms in Ilishan, Ogun State, Nigeria, determine the prevalence of tetracycline resistance/genes and presence of IS256 in enterococcal strains.
  
  
  METHODS
  Enterococci strains were isolated from 100 fresh chicken fecal samples collected from seven local poultry farms in Ilishan, Ogun State, Nigeria. The strains were identified by partial sequencing of 16S rRNA genes. Antibiotic susceptibility of the isolates to vancomycin, erythromycin, tetracycline, gentamicin, amoxycillin/claulanate, and of loxacin were performed by disc diffusion method. Detection of tet, erm, and van genes and IS256 insertion element were done by polymerase chain reaction amplification.
  
  
  RESULTS
  Sixty enterococci spp. were identified comprising of Enterococcus faecalis 33 (55%), Enterococcus casseliflavus 21 (35%), and Enterococcus gallinarium 6 (10%). All the isolates were resistant to erythromycin (100%), followed by tetracycline (81.67%), amoxicillin/clavulanic acid (73.33%), ofloxacin (68.33%), vancomycin (65%), and gentamicin (20%). None of the enterococcal spp. harbored the van and erm genes while tet(M) was detected among 23% isolates and is distributed mostly among E. casseliflavus. IS256 elements were detected only in 33% of E. casseliflavus that were also positive for tet(M) gene.
  
  
  CONCLUSIONS
  This study provides evidence that tetracycline resistance gene is present in the studied poultry farms in Ilishan, Ogun State, Nigeria and underscores the need for strict regulation on tetracycline usage in poultry farming in the studied location and consequently Nigeria.
authors.affiliation: Department of Pharmaceutical Microbiology, University of Ibadan, Nigeria, Vienna, Austria; Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety (AGES), Vienna, Austria.
authors.forename: Funmilola A
authors.initials: FA
authors.lastname: Ayeni
authors.affiliation: Department of Microbiology, University of Lagos, Akoka Yaba Lagos, Nigeria; Department of Bioscience and Biotechnology, Babcock University, Ilishan_Remo, Nigeria.
authors.forename: Bamidele Tolulope
authors.initials: BT
authors.lastname: Odumosu
authors.affiliation: Department of Bioscience and Biotechnology, Babcock University, Ilishan_Remo, Nigeria.
authors.forename: Adekola E
authors.initials: AE
authors.lastname: Oluseyi
authors.affiliation: Institute of Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety (AGES), Vienna, Austria.
authors.forename: Werner
authors.initials: W
authors.lastname: Ruppitsch
keywords: Enterococci; poultry; resistance; tet(M)