U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, Dixon, CA, USA.
California Animal Health and Food Safety Laboratory, University of California Davis, Turlock, CA, USA.
Transbound Emerg Dis. 2022 May;69(3):1095-1107. doi: 10.1111/tbed.14068. Epub 2021 May 6.
Augmentation of wild populations with captive-bred individuals presents an inherent risk of co-introducing novel pathogens to naïve species, but it can be an important tool for supplementing small or declining populations. Game species used for human enterprise and recreation such as the ring-necked pheasant (Phasianus colchicus) are commonly raised in captivity and released onto public and private wildlands as a method of augmenting naturalized pheasant populations. This study presents findings on pathogen exposure from three sources of serological data collected in California during 2014-2017 including (a) 71 pen-reared pheasants sampled across seven game bird breeding farms, (b) six previously released pen-reared pheasants captured at two study sites where wild pheasants occurred and (c) 79 wild pheasants captured across six study sites. In both pen-reared and wild pheasants, antibodies were detected against haemorrhagic enteritis virus (HEV), infectious laryngotracheitis (ILT), infectious bursal disease virus (IBDV), paramyxovirus type 1 (PMV-1) and Pasteurella multocida (PM). Previously released pen-reared pheasants were seropositive for HEV, ILT, and PM. Generalized linear mixed models accounting for intraclass correlation within groups indicated that pen-reared pheasants were more than twice as likely to test positive for HEV antibodies. Necropsy and ancillary diagnostics were performed in addition to serological testing on 40 pen-reared pheasants sampled from five of the seven farms. Pheasants from three of these farms tested positive by PCR for Siadenovirus, the causative agent of both haemorrhagic enteritis in turkeys and marble spleen disease of pheasants, which are serologically indistinguishable. Following necropsy, owners from the five farms were surveyed regarding husbandry and biosecurity practices. Farms ranged in size from 10,000 to more than 100,000 birds, two farms raised other game bird species on premises, and two farms used some form of vaccination. Biosecurity practices varied by farm, but the largest farm implemented the strictest practices.
利用圈养繁殖个体来增加野生种群存在将新病原体引入无经验物种的固有风险，但它可以成为补充小型或减少的种群的重要工具。用于人类企业和娱乐的狩猎物种，如环颈雉（Phasianus colchicus），通常在圈养中饲养，并释放到公共和私人荒地中，作为增加归化雉种群的一种方法。本研究介绍了 2014-2017 年在加利福尼亚州收集的三种血清学数据来源的病原体暴露发现，包括(a) 在七个猎鸟养殖场采集的 71 只圈养雉鸡，(b) 在两个野生雉鸡发生的研究地点捕获的六只先前释放的圈养雉鸡，(c) 在六个研究地点捕获的 79 只野生雉鸡。在圈养和野生雉鸡中，均检测到针对出血性肠炎病毒（HEV）、传染性喉气管炎（ILT）、传染性法氏囊病病毒（IBDV）、副粘病毒 1 型（PMV-1）和多杀性巴氏杆菌（PM）的抗体。先前释放的圈养雉鸡对 HEV、ILT 和 PM 呈血清阳性。考虑到组内的类内相关性，广义线性混合模型表明，圈养雉鸡对 HEV 抗体检测呈阳性的可能性是野生雉鸡的两倍多。除了血清学检测外，还对来自七个农场中的五个农场的 40 只圈养雉鸡进行了尸检和辅助诊断。来自其中三个农场的雉鸡通过 PCR 检测出禽腺病毒呈阳性，该病毒是火鸡出血性肠炎和雉鸡大理石脾病的病原体，这两种疾病在血清学上无法区分。尸检后，对五个农场的所有者进行了有关饲养和生物安全措施的调查。这些农场的规模从 10000 只到 100000 多只不等，其中两个农场在现场饲养其他狩猎鸟类物种，两个农场使用某种形式的疫苗接种。生物安全措施因农场而异，但最大的农场实施了最严格的措施。
