Derksen T, Lampron R, Hauck R, Pitesky M, Gallardo R A
A Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, 1089 Veterinary Medicine Drive VM3B, Davis, CA 95616.
B Department of Pathobiology and Department of Poultry Science, Auburn University, 302J Poultry Science Building, 260 Lem Morrison Drive, Auburn, AL 36849.
Avian Dis. 2018 Mar;62(1):1-5. doi: 10.1637/11672-050917-Reg.1.
Raising backyard chickens is an ever-growing hobby in the United States. These flocks can be a substrate for respiratory disease amplification and transmission to commercial facilities. Five hundred fifty-four chickens from 41 backyard flocks were sampled in this study. ELISA kits were used to detect antibodies against avian influenza (AI), infectious laryngotracheitis (ILT), Newcastle disease (ND), infectious bronchitis (IB), Ornithobacterium rhinotracheale (ORT), Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS). All visited flock owners answered a biosecurity questionnaire that assessed biosecurity measures. The questionnaire revealed that backyard poultry owners lack simple biosecurity measures such as use of dedicated shoes, their chicken sources are unreliable, and few of them benefit from veterinary oversight. Only one flock had a clear vaccination history against ND and IB. ORT, ND, IB, MS, MG, and ILT were the most seroprevalent in backyard poultry flocks with 97% (41/42), 77.5% (31/40), 75% (30/40), 73% (31/42), 69% (29/42), and 45% (19/42), respectively. The vaccinated flock was not considered in these calculations. When examining the distance between backyard flocks and the nearest commercial poultry facility, ND and MG were significantly more likely to be found in backyard flocks close to (<4 miles) whereas ORT was significantly more likely in backyard chickens located far from (>4 miles) commercial poultry. Birds purchased directly from National Poultry Improvement Plan hatcheries showed a reduced ND, MG, and MS antibody prevalence. Wearing dedicated shoes decreased MS antibody-positive birds. Finally, history of wild bird contact had a clear effect on an increased seroprevalence of NDV and MG. Serological results suggest that backyard poultry flocks have the potential to serve as a reservoir or amplifier for poultry respiratory diseases. The information generated in this project should direct extension efforts toward emphasizing the importance of small flock biosecurity and chick acquisition sources.
在美国，饲养后院鸡已成为一种日益流行的爱好。这些鸡群可能成为呼吸道疾病传播和扩散到商业养殖场的媒介。本研究对来自41个后院鸡群的554只鸡进行了采样。使用酶联免疫吸附测定（ELISA）试剂盒检测针对禽流感（AI）、传染性喉气管炎（ILT）、新城疫（ND）、传染性支气管炎（IB）、禽气管鸟杆菌（ORT）、鸡毒支原体（MG）和滑膜支原体（MS）的抗体。所有受访的鸡群主人都回答了一份生物安全调查问卷，该问卷评估了生物安全措施。问卷显示，后院家禽主人缺乏一些简单的生物安全措施，如使用专用鞋，他们的鸡源不可靠，而且很少有人能得到兽医的监管。只有一个鸡群有明确的新城疫和传染性支气管炎疫苗接种史。ORT、ND、IB、MS、MG和ILT是后院家禽群中血清阳性率最高的疾病，分别为97%（41/42）、77.5%（31/40）、75%（30/40）、73%（31/42）、69%（29/42）和45%（19/42）。计算中未考虑已接种疫苗的鸡群。在检查后院鸡群与最近的商业家禽养殖场之间的距离时，发现距离商业家禽养殖场较近（<4英里）的后院鸡群中，ND和MG的感染率显著更高，而距离较远（>4英里）的后院鸡群中ORT的感染率显著更高。直接从国家家禽改良计划孵化场购买的鸡，其ND、MG和MS抗体阳性率较低。穿专用鞋可降低MS抗体阳性鸡的比例。最后，与野生鸟类接触的历史对新城疫病毒（NDV）和MG血清阳性率的增加有明显影响。血清学结果表明，后院家禽群有可能成为家禽呼吸道疾病的储存宿主或放大器。本项目所产生的信息应指导推广工作，强调小型鸡群生物安全和雏鸡获取来源的重要性。
