Long Kathleen E, Ouckama Rachel M, Weisz Alexandru, Brash Marina L, Ojkić Davor
A Maple Leaf Foods, 70 Heritage Drive, New Hamburg, Ontario, Canada N3A 2J4.
B Maple Lodge Hatcheries, 101 Fox Road, Port Hope, Ontario, Canada L1A 3V6.
Avian Dis. 2018 Jun;62(2):247-258. doi: 10.1637/11802-012018-Case.1.
Sixty-four cases of white chick syndrome (WCS) in broiler breeders producing affected progeny were reported from seven hatcheries in Ontario, Canada, between 2009 and 2016, with 43 of those originating from two hatcheries owned by a single company. WCS cases were identified by the presence of typical chicks in the hatchery that were generally weak with pale to white down, enlarged abdomens, and occasionally brown wiry fluff on the dorsum of the neck. Affected embryos and chicks had characteristic gross and histologic liver lesions, and livers were positive for chicken astrovirus (CAstV) RNA by real-time reverse transcriptase PCR. Affected broiler breeder flocks experienced egg production drops of 0% to 21% and hatchability drops of 0% to 68.4%. The amino acid sequence of the region encoding the capsid gene of WCS viruses demonstrated all Ontario CAstV to be in Group B, Subgroup Bii.
2009年至2016年间，加拿大安大略省的7家孵化场报告了64例种鸡感染白羽鸡综合征（WCS）并产出受影响后代的病例，其中43例来自同一家公司旗下的两家孵化场。在孵化场中，典型的患病雏鸡表现为普遍虚弱、绒毛颜色从浅色到白色、腹部肿大，偶尔颈部背面有棕色硬毛状绒毛，据此可识别出WCS病例。受影响的胚胎和雏鸡有典型的肝脏大体病变和组织学病变，通过实时逆转录聚合酶链反应检测，肝脏中鸡星状病毒（CAstV）RNA呈阳性。受影响的种鸡群产蛋量下降了0%至21%，孵化率下降了0%至68.4%。WCS病毒衣壳基因编码区的氨基酸序列表明，安大略省所有的CAstV均属于B组Bii亚组。
