Sun Yani, Du Taofeng, Liu Baoyuan, Syed Shahid Faraz, Chen Yiyang, Li Huixia, Wang Xinjie, Zhang Gaiping, Zhou En-Min, Zhao Qin
Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Scientific Observing and Experimental Station of Veterinary Pharmacology and Veterinary Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, 712100, China.
BMC Vet Res. 2016 Nov 22;12(1):261. doi: 10.1186/s12917-016-0892-4.
From 2014 to 2015 in China, many broiler breeder and layer hen flocks exhibited a decrease in egg production and some chickens developed hepatitis syndrome including hepatomegaly, hepatic necrosis and hemorrhage. Avian hepatitis E virus (HEV) and avian leucosis virus subgroup J (ALV-J) both cause decreasing in egg production, hepatomegaly and hepatic hemorrhage in broiler breeder and layer hens. In the study, the seroprevalence of avian HEV and ALV-J in these flocks emerging the disease from Shandong and Shaanxi provinces were investigated.
A total of 1995 serum samples were collected from 14 flocks with hepatitis syndrome in Shandong and Shaanxi provinces, China. Antibodies against avian HEV and ALV-J in these serum samples were detected using iELISAs. The seroprevalence of anti-avian HEV antibodies (35.09%) was significantly higher than that of anti-ALV-J antibodies (2.16%) (p = 0.00). Moreover, the 43 serum samples positive for anti-ALV-J antibodies were all also positive for anti-avian HEV antibodies. In a comparison of both provinces, Shandong chickens exhibited a significantly higher seroprevalence of anti-avian HEV antibodies (42.16%) than Shaanxi chickens (26%) (p = 0.00). In addition, the detection of avian HEV RNA and ALV-J cDNA in the liver samples from the flocks of two provinces also showed the same results of the seroprevalence.
In the present study, the results showed that avian HEV infection is widely prevalent and ALV-J infection is endemic in the flocks with hepatitis syndrome from Shandong and Shaanxi provinces of China. These results suggested that avian HEV infection may be the major cause of increased egg drop and hepatitis syndrome observed during the last 2 years in China. These results should be useful to guide development of prevention and control measures to control the diseases within chicken flocks in China.
2014年至2015年期间，中国许多肉种鸡和蛋鸡群产蛋量下降，部分鸡只出现肝炎综合征，包括肝脏肿大、肝坏死和出血。禽戊型肝炎病毒（HEV）和禽白血病病毒J亚群（ALV-J）均可导致肉种鸡和蛋鸡产蛋量下降、肝脏肿大和肝出血。本研究对山东和陕西出现该疾病的鸡群中禽HEV和ALV-J的血清流行率进行了调查。
从中国山东和陕西的14个患有肝炎综合征的鸡群中总共采集了1995份血清样本。使用间接酶联免疫吸附测定法（iELISA）检测这些血清样本中抗禽HEV和ALV-J的抗体。抗禽HEV抗体的血清流行率（35.09%）显著高于抗ALV-J抗体的血清流行率（2.16%）（p = 0.00）。此外，43份抗ALV-J抗体呈阳性的血清样本抗禽HEV抗体也均为阳性。在两省的比较中，山东鸡抗禽HEV抗体的血清流行率（42.16%）显著高于陕西鸡（26%）（p = 0.00）。此外，对两省鸡群肝脏样本中禽HEV RNA和ALV-J cDNA的检测也显示出与血清流行率相同的结果。
在本研究中，结果表明禽HEV感染在中国山东和陕西患有肝炎综合征的鸡群中广泛流行，而ALV-J感染为地方流行。这些结果表明，禽HEV感染可能是中国过去两年观察到的产蛋下降和肝炎综合征增加的主要原因。这些结果对于指导制定中国鸡群疾病防控措施应是有用的。
