Abstract：
To investigate the prevalence of avian hepatitis E virus (HEV) in chickens and gather evidence of viral vertical transmission, we collected 288 cloacal swabs and 288 yolks samples from 12 farms with clinically healthy chickens in 4 different areas in Tai\'an City, Shandong Province, China (i.e., Daiyue District, Xintai City, Feicheng City, and Ningyang County). We also collected 240 samples from 2 breeder farms (from each of which 30 chicks, 30 dead embryos, 30 live embryos, and 30 hatching eggs were taken). PCR detection revealed that the positive rates of cloacal swabs and yolks were 6.25% (18/288) and 4.51% (13/288), respectively. Besides, avian HEV was detected with higher positive rates in the chicks (11.67%), hatching eggs (10.00%), live embryos (13.33%), and dead embryos (26.67%) from 2 breeder farms. Sequence and genetic evolution analyses revealed that the nucleotide homology of the isolated strains was 76.4to 83.9% compared with 4 reported genotypes, but the isolated strains were located in a separate branch, indicating they were potential novel genotypes. In conclusion, those results indicate that the latent infection of avian HEV novel genotypes has been widespread in chicken farms in Tai\'an City, and provide reliable evidence of the possible vertical transmission of avian HEV.
摘要：
调查禽戊型肝炎病毒（HEV）在鸡中的流行情况，并收集病毒垂直传播的证据，我们收集了来自12个农场的288个泄殖腔拭子和288个蛋黄样本，在泰安市4个不同地区的临床健康鸡，山东省,中国(即，黛岳区,新泰市,肥城市,和宁阳县）。我们还从2个饲养场收集了240个样本(每个饲养场30只小鸡，30个死亡胚胎,30个活胚胎,取30个孵化卵)。PCR检测显示，泄殖腔拭子和蛋黄的阳性率分别为6.25％（18/288）和4.51％（13/288）。分别。此外,禽类HEV在雏鸡中检测到较高的阳性率（11.67％），孵化卵(10.00%)，活胚胎(13.33%),和2个饲养场的死胚胎(26.67%)。序列和遗传进化分析表明，与4种报道的基因型相比，分离菌株的核苷酸同源性为76.4％至83.9％。但是分离的菌株位于一个单独的分支中，表明它们是潜在的新型基因型。总之,这些结果表明，禽HEV新型基因型的潜伏感染在泰安市的养鸡场中普遍存在，并为禽类HEV可能的垂直传播提供可靠的证据。
