Burns Theresa E, Kelton David, Ribble Carl, Stephen Craig
Department of Population Medicine, University of Guelph, 21 Stone Road, Guelph, Ontario N1G 2W1, Canada.
Avian Dis. 2011 Sep;55(3):350-7. doi: 10.1637/9646-010411-Reg.1.
Understanding normal movement patterns and husbandry practices of poultry production systems is important for understanding the dynamics of disease spread, and for controlling outbreaks of highly infectious diseases, such as highly pathogenic avian influenza. To learn about these patterns in the noncommercial or "backyard" poultry-keeping sector, an open-ended questionnaire was administered to 18 backyard-flock owners in British Columbia, Canada, and responses were analyzed descriptively. Six participants reported that they visited premises that were part of the commercial poultry system in the last year; however, bird movements between commercial and noncommercial farms were always unidirectional, from commercial to backyard. Bird movements into and out of participants' flocks occurred multiple times per month (two flocks), three times per year (five flocks), once or twice a year (nine flocks) and every 3-5 yr (two flocks). Visitors had direct contact with three participants' flocks multiple times per week; for other flocks, visitors had direct contact three times or less per year. Fourteen participants rarely had direct contact with other backyard flocks, three had contact more than once per week, and one had contact every 3 mo. Participants stated that the health of their birds was excellent (7), very good (3), good (6), O.K. (1), and all right (1), and used a median of two biosecurity practices to maintain health in their flock. Our findings suggest that bird movements are not likely to transmit disease from backyard to commercial flocks; however, human movements between backyard and commercial premises could transmit diseases. Within the backyard-flock sector, the majority of small flocks appear to pose little risk of disease transmission because they are maintained in semi-isolation from other flocks; however, a minority of flocks has high contact levels with other flocks and could be important in disease spread.
了解家禽生产系统的正常运动模式和饲养方式对于理解疾病传播动态以及控制高传染性疾病（如高致病性禽流感）的爆发至关重要。为了了解非商业性或“后院”家禽养殖部门的这些模式，我们对加拿大不列颠哥伦比亚省的18位后院鸡群养殖户进行了开放式问卷调查，并对调查结果进行了描述性分析。6名参与者报告称，他们在过去一年中参观过商业家禽系统的场所；然而，商业农场和非商业农场之间的禽类流动始终是单向的，从商业农场流向后院。进出参与者鸡群的禽类流动每月发生多次（两个鸡群）、每年发生三次（五个鸡群）、每年发生一到两次（九个鸡群）以及每3至5年发生一次（两个鸡群）。访客每周多次与三名参与者的鸡群有直接接触；对于其他鸡群，访客每年有三次或更少的直接接触。14名参与者很少与其他后院鸡群有直接接触，三名参与者每周有一次以上的接触，一名参与者每三个月有一次接触。参与者表示他们鸡群的健康状况极佳（7人）、非常好（3人）、良好（6人）、尚可（1人）以及还可以（1人），并且平均采用两种生物安全措施来保持鸡群健康。我们的研究结果表明，禽类流动不太可能将疾病从后院鸡群传播到商业鸡群；然而，后院和商业场所之间的人员流动可能会传播疾病。在后院鸡群部门内，大多数小群鸡似乎疾病传播风险很小，因为它们与其他鸡群保持半隔离状态；然而，少数鸡群与其他鸡群有高度接触，可能在疾病传播中起重要作用。
