鸡马立克氏病毒和网状内皮增生病毒感染肉鸡时的相互作用

Interaction of Marek’s Disease Virus and Reticuloendotheliosis Virus in Co-infected Broilers

为了研究鸡马立克氏病病毒(MDV)和网状内皮增生病病毒(REV)共感染时的相互作用,分别在REV母源抗体阳性(REV-Ab+)和阴性(REV-Abˉ)及经MDV疫苗CVI988株免疫和不免疫的商品代肉鸡,比较了二种病毒在病毒血症水平和特异抗体效价上的相互影响。结果表明,在未经CVI988株免疫鸡,REV病毒血症对MDV强毒接种后的病毒血症水平及抗体效价无明显影响,但REV病毒血症显著抑制了CVI988疫苗免疫为鸡提供的抵抗力和抗体效价,因而提高了强毒MDV感染后的病毒血症的程度。另一方面,MDV感染会显著减弱REV-Ab+鸡对REV感染的抵抗力,提高REV-Ab+鸡在感染REV后的病毒血症水平并抑制对它的抗体效价。分析表明,MDV和REV共感染主要通过抑制鸡体的免疫功能来影响另一种病毒的复制及其致病作用。

To understand the interaction between Marek＇s disease viruses （MDV） and Reticuloendothe -liosis viruses （REV） in co-infected chickens, their mutual influences on vriremia levels and specific antibody titiers were studied in REV maternal antibody positive （REV-ab^＋） or negative （REV-ab^-） commercial broilers vaccinated with or without MDV vaccine CVI988. The results indicated that REV viremia did not influence the MDV viremia level and antibody titers after inoculation with virulent MDV in unvaccinated chickens. In chickens vaccinated with CVI988, however, REV viremia could significantly inhibit antibody titers （p〈0.01） and resistance to MDV, and compromised protective effect of CVI988 vaccine from MDV viremia in vaccinated birds. In another hand, MDV infection could decrease the resistance to REV infection in REV-ab^＋ chickens. REV inoculation caused no REV viremia in REV-ab^＋ chickens without MDV viremia but caused high titers of REV viremia in REV-ab^＋ chickens with MDV viremia. MDV viremia also decreased antibody responses to REV inoculation in REV-ab^＋ chickens. Analysis of the data suggested that co-infection of MDV and REV could influence each other＇s pathogenicity mainly through their inbibitory effects on chicken＇s immune functions.