Prevalence and Subtypes of Ciprofloxacin-Resistant Campylobacter spp. in Commercial Poultry Flocks before, during, and after Treatment with Fluoroquinolones

Abstract

Five commercial broiler chicken flocks were treated with either difloxacin or enrofloxacin for a clinically relevant infection, as instructed by a veterinarian. Campylobacters were isolated from individual fecal samples and from samples associated with the broiler environment before, during, and after treatment. Ciprofloxacinresistant Campylobacter jejuni and/or C. coli strains were detected pretreatment in four flocks, but they constituted a very small proportion of the campylobacters present. When the broilers were treated with a fluoroquinolone, a rapid increase in the proportion of ciprofloxacin-resistant campylobacters was observed. During treatment nearly 100% of campylobacters were resistant, and in some flocks a high proportion of resistant strains persisted for up to 4 weeks after treatment. Prior to treatment a variety of campylobacter subtypes were present. During and after treatment considerable changes in both species and subtype prevalence were observed, but no single fluoroquinolone-resistant clone became dominant. Instead, resistant C. coli strains or a mixture of resistant C. coli and C. jejuni strains became dominant, whereas susceptible C. jejuni strains had usually been dominant prior to treatment. The resistant subtypes which emerged and became dominant were not always the same as those detected pretreatment.

The Dynamics of Antimicrobial-Resistant Campylobacter jejuni on Japanese Broiler Farms

“…was observed on broiler flocks prior to treatment and the percentage of FQ-resistant isolates increased during treatment with FQ. The FQ-resistant Campylobacter subtypes which emerged either during or after treatment did not necessarily belong to the same subtypes which had been prevalent before treatment [5]. Though drugs had never been used on the flocks studied, fluctuation of antimicrobial resistant C. jejuni isolates was observed in the present study.…”

“…A similar change of the predominant clone [13] and the colonisation phenotypes [20] in chickens were reported. Humphrey et al [5] have reported that a small proportion of FQresistant Campylobacter spp. was observed on broiler flocks prior to treatment and the percentage of FQ-resistant isolates increased during treatment with FQ.…”

Detection of fluoroquinolone resistance by mutation in gyrA gene of Campylobacter spp. isolates from broiler and laying (Gallus gallus domesticus) hens,from Rio de Janeiro State, Brazil

“…strains isolated from poultry reveals the impact of the use of these antibiotics in poultry production (ENDTZ et al, 1991;SMITH et al, 1999;ENGBERG et al, 2004;HUMPHREY et al, 2005). Resistance levels vary according to the country, variable factors including the permission to use this drug in poultry production (CHEN et al, 2010).…”

β-Lactamase-Mediated β-Lactam Resistance in Campylobacter Species: Prevalence of Cj0299 ( bla OXA-61 ) and Evidence for a Novel β-Lactamase in C . jejuni

“…Bacterial strains were isolated between 2000 and 2006 from chicken flocks in the United Kingdom, during studies OZO501 and VMO2200 funded by the Department for Environment, Food and Rural Affairs (9,10,19; N. C. Elviss, L. K. Williams, F. Jorgensen, S. A. Chisholm, A. J. Lawson, C. Swift, R. J. Owen, D. J. Griggs, M. M. Johnson, T. J. Humphrey, and L. J. V. Piddock, submitted for publication). In total, 1,288 Campylobacter isolates were studied; 967 of the isolates were C. jejuni, 319 were C. coli, and 2 were C. lari.…”