title: Prevalence and antimicrobial resistance among Campylobacter spp. in Louisiana retail chickens after the enrofloxacin ban.
abstract: Effective in September 2005, enrofloxacin, a fluoroquinolone group antimicrobial, was withdrawn from use in the U.S. poultry farms. In this 1-year study initiated in October 2006, we isolated and characterized Campylobacter spp. from Louisiana retail conventionally raised (n = 141) and organic (n = 53) chickens as a comparison to evaluate the postban bacterial resistance to antimicrobials. Campylobacter was present in 43.3% of the chickens; similar rates were observed among conventional and organic chickens. A total of 165 Campylobacter isolates were recovered, with Campylobacter jejuni being the predominant species (66.7%). No apparent seasonal trend was deduced from the prevalence data. Further, the two main conventional and one organic chicken brands did not carry significantly different rates of Campylobacter (p > 0.05). The most common resistance observed was to tetracycline (31.5%), followed by erythromycin (20%) and ciprofloxacin (6.1%). No resistance to gentamicin was identified. All Campylobacter isolates recovered from organic chickens (n = 48) were susceptible to ciprofloxacin, compared to 8.5% resistance rate for those from conventional chickens (n = 117). Additionally, the resistance rate to erythromycin was significantly higher in Campylobacter isolates from conventional chickens (23.9%) than those from organic chickens (10.4%; p < 0.05). Our results demonstrated a low prevalence and low ciprofloxacin resistance rate of Campylobacter in Louisiana retail chickens after the enrofloxacin ban. Further studies involving a larger sample size over time are warranted to better assess the effects of banning enrofloxacin use in poultry and the levels of fluoroquinolone-resistant Campylobacter.
authors.affiliation: Department of Food Science, Louisiana State University Agricultural Center, Baton Rouge, Louisiana 70803, USA.
authors.forename: Feifei
authors.initials: F
authors.lastname: Han
authors.forename: Shofiyah Ika
authors.initials: SI
authors.lastname: Lestari
authors.forename: Shuaihua
authors.initials: S
authors.lastname: Pu
authors.forename: Beilei
authors.initials: B
authors.lastname: Ge
mesh_terms: D000822:Animal Husbandry / Q000379:methods; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002167:Campylobacter / Q000187:drug effects* / Q000302:isolation & purification; D002169:Campylobacter Infections / Q000188:drug therapy / Q000382:microbiology / Q000635:transmission / Q000662:veterinary*; D016123:Campylobacter jejuni / Q000187:drug effects / Q000302:isolation & purification; D002645:Chickens; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial; D000077422:Enrofloxacin; D024841:Fluoroquinolones / Q000008:administration & dosage / Q000494:pharmacology; D005506:Food Contamination / Q000032:analysis* / Q000517:prevention & control; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D011201:Poultry Diseases / Q000188:drug therapy* / Q000382:microbiology / Q000635:transmission; D015995:Prevalence; D011897:Random Allocation
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D000077422:Enrofloxacin