Tsiouris Vasileios, Mantzios Tilemachos, Kiskinis Konstantinos, Guérin Jean-Luc, Croville Guillaume, Brellou Georgia D, Apostolopoulou Emmanouela P, Petridou Evanthia J, Georgopoulou Ioanna
Unit of Avian Medicine, Clinic of Farm Animals, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54627 Thessaloniki, Greece.
IHAP, Université de Toulouse, INRAE, ENVT, 31300 Toulouse, France.
Vet Sci. 2022 Mar 25;9(4):160. doi: 10.3390/vetsci9040160.
Inclusion body hepatitis (IBH) is an economically important disease of chickens, with a worldwide distribution, caused by Fowl Aviadenoviruses (FAdVs). Currently, the increased number of cases, the virulence of the isolate strains, as well as the lack of cross-species protection highlight that detailed in-field data are fundamental for the development of successful control strategies. This case report provides a detailed clinicopathological investigation of an unusual IBH outbreak in a commercial broiler farm in the region of Macedonia, Greece. The farm consisted of 64,000 birds, originated from the same breeder stock and placed in three different houses (Flock A-C). At 20 days of age, a sudden increase in daily mortality was recorded in Flock A. It is worth mentioning that, although all flocks were serologically (indirect ELISA) and molecularly (RT-PCR) positive for FAdV, the mortality rate, attributed to IBH, was much higher in Flock A compared to others. The clinical manifestation included non-specific symptoms such as depression, inappetence, yellowish mucoid diarrhea, and lack of uniformity. At necropsy, typically, enlarged, pale, and friable livers were dominant, while sporadically lesions were recorded in the pancreas, kidneys, skeletal muscles, and lymphoid organs. The histopathological examination of liver samples showed multifocal inflammation, necrosis, and the presence of basophilic/ eosinophilic inclusion bodies in hepatocytes. In addition, the loss of the architecture of pancreatic lobules and the presence of fibrosis and foci of mononuclear cell aggregates were suggestive of chronic pancreatic inflammation. PCR analysis confirmed the presence of FAdV, belonging to species E, serotype FAdV-8b. Performance and financial calculations revealed that IBH increased Feed Conversion Ratio (FCR), feed cost/chick as well as feed cost/kg live weight, whereas the Livability (%) and the European Production Efficiency Factor (EPEF) were decreased in the most severely affected flocks (Flock A). This study is the first report of the detection and identification of FAdV serotypes associated with IBH in commercial broiler flocks in Greece. However, there is still a lack of information about the circulating FAdV serotypes in the country, and therefore epidemiological studies are needed to establish control strategies for IBH.
包涵体肝炎（IBH）是一种在经济上对鸡具有重要影响的疾病，在全球范围内均有分布，由禽腺病毒（FAdVs）引起。目前，病例数量的增加、分离毒株的毒力以及缺乏跨物种保护表明，详细的现场数据对于制定成功的控制策略至关重要。本病例报告提供了对希腊马其顿地区一个商业肉鸡场发生的一次不寻常的IBH疫情的详细临床病理学调查。该养殖场有64000只鸡，来自同一批种鸡，饲养在三个不同的鸡舍（鸡群A - C）。在20日龄时，鸡群A的日死亡率突然上升。值得一提的是，尽管所有鸡群在血清学（间接ELISA）和分子学（RT - PCR）检测中FAdV均呈阳性，但与其他鸡群相比，鸡群A中归因于IBH的死亡率要高得多。临床表现包括抑郁、食欲不振、黄色黏液样腹泻和生长不均一等非特异性症状。尸检时，通常可见肝脏肿大、苍白且易碎，同时在胰腺、肾脏、骨骼肌和淋巴器官中偶尔也有病变记录。肝脏样本的组织病理学检查显示多灶性炎症、坏死以及肝细胞中存在嗜碱性/嗜酸性包涵体。此外，胰腺小叶结构的破坏以及纤维化和单核细胞聚集灶的存在提示存在慢性胰腺炎症。PCR分析证实存在属于E种、血清型为FAdV - 8b的FAdV。生产性能和财务计算表明，IBH增加了饲料转化率（FCR）、每只鸡的饲料成本以及每千克活重的饲料成本，而在受影响最严重的鸡群（鸡群A）中，成活率（%）和欧洲生产效率因子（EPEF）有所下降。本研究是希腊商业肉鸡群中与IBH相关的FAdV血清型检测与鉴定的首次报告。然而，该国关于流行的FAdV血清型仍缺乏信息，因此需要进行流行病学研究以制定IBH的控制策略。
