Veterinary Diagnostic Laboratory and Department of Veterinary Population Medicine College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108.
U.P. Pt. Deen Dayal Upadhyaya Veterinary Science University and Cattle Research Institute (DUVASU), Mathura, UP 281001, India.
Avian Dis. 2020 Dec 1;64(4):471-477. doi: 10.1637/0005-2086-64.4.471.
Since August 2014, the University of Minnesota Veterinary Diagnostic Laboratory has received cases of turkey enteritis that are clinically different from previously described cases of poult enteritis syndrome and light turkey syndrome. The birds develop dark green and extremely foul-smelling diarrhea starting at 8-10 wk of age, which may last up to 15-16 wk of age. The affected turkey flocks show poor uniformity, and feed conversion and market weights are reduced. Multiple-age farms are affected more often than the single-age farms. Morbidity varies from flock to flock and in some cases reaches 100%. At necropsy, undigested feed with increased mucus is observed in the intestines along with prominent mucosal congestion and/or hemorrhage. Microscopically, lymphocytic infiltrates expand the villi in duodenum and jejunum to form lymphoid follicles, which are often accompanied by heterophils. Next generation sequencing (Illumina Miseq) on a pool of feces from affected birds identified genetic sequences of viruses belonging to Astroviridae, Reoviridae, Picornaviridae, Picobirnaviridae, and Adenoviridae. On testing pools of fecal samples from apparently healthy (16 pools) and affected birds (30 pools), there was a higher viral load in the feces of affected birds. Picobirnavirus was detected only in the affected birds; 20 of 30 pools (66.7%) were positive. These results indicate that a high viral load of turkey picobirnavirus alone, or in association with novel picornaviruses, may be a cause of this new type of turkey enteritis.
自 2014 年 8 月以来，明尼苏达大学兽医诊断实验室收到了一些与以前描述的雏鸡肠炎综合征和轻型火鸡综合征不同的火鸡肠炎病例。这些鸡在 8-10 周龄时开始出现深绿色且气味极难闻的腹泻，可持续至 15-16 周龄。受影响的火鸡群均匀度较差，饲料转化率和上市体重降低。多龄农场比单龄农场更容易受到影响。发病率因鸡群而异，在某些情况下可达 100%。剖检时，可见肠道中未消化的饲料伴有增多的黏液，同时伴有明显的黏膜充血和/或出血。组织学上，十二指肠和空肠的绒毛被淋巴细胞浸润，形成淋巴滤泡，常伴有嗜中性粒细胞。对来自受影响鸟类粪便的混合样本进行下一代测序（Illumina Miseq），鉴定出属于星状病毒科、呼肠孤病毒科、小核糖核酸病毒科、细小病毒科和腺病毒科的病毒的遗传序列。在对来自明显健康（16 个样本池）和受影响鸟类（30 个样本池）的粪便样本进行测试时，受影响鸟类粪便中的病毒载量更高。仅在受影响的鸟类中检测到细小病毒科；30 个样本池中有 20 个（66.7%）呈阳性。这些结果表明，火鸡细小病毒科的高病毒载量，或与新型小核糖核酸病毒科一起，可能是这种新型火鸡肠炎的原因。
