自然感染鸭坦布苏病毒蛋鸭卵巢的病理学观察

Pathological Observation on the Ovary of Laying Ducks after Natural Infection with Duck Tembusu Virus

鸭坦布苏病毒(DTMUV)感染是引起蛋鸭产蛋下降的疾病,给禽类养殖业带来极大的经济损失。本研究对DTMUV感染病鸭卵巢的病毒定位及产生的病理损伤进行观察,以了解DTMUV对病鸭卵巢的病理损伤。主要运用病理剖检、常规石蜡切片及HE染色、免疫组织化学等技术对自然感染DTMUV的病鸭进行研究。结果显示:感染蛋鸭临床表现主要以产蛋量骤然下降为特征,严重病例站立不稳,倒地抽搐,最后衰竭而死。剖检眼观病变表现为卵泡充血、出血,破裂,组织病理学变化主要是生长卵泡和成熟卵泡的颗粒细胞增生、凋亡或坏死;卵泡周围有大量空泡状细胞和小动脉增生,增生的动脉平滑肌细胞坏死,大量炎性细胞浸润;免疫组织化学检测结果显示增生的空泡状细胞为上皮细胞,DTMUV主要位于卵泡的颗粒细胞内。综上表明,DTMUV主要分布在颗粒细胞内,颗粒细胞发生增生、凋亡或坏死,导致卵泡闭锁,进而引起蛋鸭产蛋量下降,为阐明DTMUV的感染机制提供理论基础。

Duck tembusu virus(DTMUV)infection is a disease that causes a decline in laying ducks and brings great economic losses to the poultry breeding industry.In this study,the virus location and pathological damage of DTMUV-infected duck ovaries were observed to understand the effect of DTMUV on ovarian damage.Pathological necropsy,routine paraffin sections,HE staining,and immunohistochemistry were used to study diseased ducks naturally infected with DTMUV.The clinical manifestations of laying ducks were mainly characterized by a sudden drop in egg production.In severe cases,they could not stand steady,fell to the ground and convulsed,and finally died of exhaustion.Necropsy showed that follicles were hemorrhage and rupture.Histopathological changes were mainly the proliferation,apoptosis or necrosis of granulosa cells in growing follicles and mature follicles;there were a large number of vacuolar cells and small arteries around the follicles.Arterial smooth muscle cell necrosis and a large number of inflammatory cells infiltrated;immunohistochemical examination results showed that the proliferating vacuolar cells are epithelial cells,and DTMUV is mainly located in the granular cells of the follicles.According to the observation results,DTMUV is mainly distributed in the granulosa cells.The granulosa cells proliferate,apoptosis or necrosis,which leads to follicle atresia,and causes the egg production of laying ducks to decrease.It provided a theoretical basis for elucidating the pathogenic mechanism of DTMUV infection.