Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA.
Appl Environ Microbiol. 2012 Apr;78(8):2698-705. doi: 10.1128/AEM.07723-11. Epub 2012 Feb 3.
The objectives of this study were to compare and characterize the prevalence of antimicrobial-resistant (AR) Campylobacter in conventional and antimicrobial-free (ABF) production systems on farms, at slaughter, and in the environment. Fecal and environmental samples were collected from ABF farms (pigs, 1,239; environment, 797) and conventional farms (pigs, 1,650; environment, 1,325). At slaughter, we collected samples from carcasses, including postevisceration swabs, postchill swabs, and mesenteric lymph nodes from ABF systems (postevisceration swabs, 182; postchill swabs, 199; mesenteric lymph nodes, 184) and conventional systems (postevisceration swabs, 272; postchill swabs, 271; mesenteric lymph nodes, 255) at separate processing facilities. We also sampled the processing plant environment, including truck and lairage floor swab samples (ABF, 115; conventional, 90). Overall, a total of 2,908 Campylobacter isolates, including Campylobacter coli (farm, 2,557, 99.8%; slaughter, 341, 98.3%) and Campylobacter jejuni (farm, 4, 0.2%; slaughter, 6, 1.7%), were isolated in the study. There was no significant difference in the prevalence of Campylobacter between ABF and conventionally raised pigs (farrowing, P = 0.20; nursery, P = 0.06; finishing, P = 0.24) and the environment (P = 0.37). At slaughter, Campylobacter was isolated from all of the stages, including postchill. The highest frequencies of resistance were exhibited against tetracycline (ABF, 48.2%; conventional, 88.3%). Ciprofloxacin-resistant C. coli isolates were observed in conventionally raised (17.1%) and ABF (1.2%) pigs (P = 0.11). Antimicrobial use data from conventional farms indicated significant associations between oxytetracycline use and tetracycline resistance in the nursery pigs (P = 0.01), between tiamulin exposure and azithromycin and erythromycin resistance in nursery (P < 0.01) and finishing (P < 0.01) pigs, and between enrofloxacin exposure and ciprofloxacin and nalidixic acid resistance in farrowing (P < 0.01) and nursery (P < 0.01) pigs. Identical antimicrobial resistance profiles were observed in the pigs and their environments on farms and at slaughter. In summary, our results highlight the persistence and dissemination of AR Campylobacter from farm to slaughter in ABF and conventionally raised pigs and their environments.
本研究的目的是比较和描述常规和无抗生素（ABF）生产系统中农场、屠宰场和环境中抗微生物药物耐药（AR）弯曲杆菌的流行情况。从 ABF 农场（猪，1239 份；环境，797 份）和常规农场（猪，1650 份；环境，1325 份）采集粪便和环境样本。在屠宰时，我们从胴体采集样本，包括剖腹后拭子、冷藏后拭子和肠系膜淋巴结，来自 ABF 系统（剖腹后拭子，182 份；冷藏后拭子，199 份；肠系膜淋巴结，184 份）和常规系统（剖腹后拭子，272 份；冷藏后拭子，271 份；肠系膜淋巴结，255 份）在不同的加工设施中。我们还对加工厂环境进行了采样，包括卡车和畜栏地板拭子样本（ABF，115 份；常规，90 份）。在这项研究中，共分离出 2908 株弯曲杆菌，包括弯曲杆菌科（农场，2557 株，99.8%；屠宰场，341 株，98.3%）和空肠弯曲杆菌（农场，4 株，0.2%；屠宰场，6 株，1.7%）。ABF 和常规饲养的猪（分娩，P = 0.20；保育，P = 0.06；育肥，P = 0.24）和环境（P = 0.37）之间的弯曲杆菌流行率无显著差异。在屠宰时，从所有阶段都分离出了弯曲杆菌，包括冷藏后。对四环素的耐药率最高（ABF，48.2%；常规，88.3%）。在常规饲养（17.1%）和 ABF（1.2%）猪中观察到对环丙沙星的耐药空肠弯曲杆菌分离株（P = 0.11）。常规农场的抗生素使用数据表明，在保育猪中，土霉素的使用与四环素的耐药性呈显著相关（P = 0.01），在保育猪（P < 0.01）和育肥猪（P < 0.01）中，替米考星暴露与阿奇霉素和红霉素的耐药性呈显著相关，在分娩猪（P < 0.01）和保育猪（P < 0.01）中，恩诺沙星暴露与环丙沙星和萘啶酸的耐药性呈显著相关。在农场和屠宰场，猪及其环境中观察到相同的抗生素耐药谱。总之，我们的研究结果突出了 ABF 和常规饲养的猪及其环境中从农场到屠宰场的抗微生物药物耐药弯曲杆菌的持续存在和传播。
