Reactions of maternal antibody to inactivated growth and its immunosuppressive effect by reticuloendotheliosis virus infection

Chinese. 确定经禽网状内皮增生病病毒（REV）细胞适应毒免疫的种鸡提供的母源抗体在雏鸡抗REV感染中的保护性免疫作用。分别对有母源抗体和无母源抗体的雏鸡人工感染REV野毒，比较它们的生长速度和对新城疫病毒（NDV）和禽流感病毒(AIV)灭活苗免疫后的抗体反应。在没有REV母源抗体的商品代肉鸡，1日龄感染REV不仅造成生长迟缓，还会显著抑制对NDV和AIV (H5和H9）疫苗的免疫反应。由致弱的REV疫苗免疫的父母代种鸡提供的母源抗体，不仅可预防REV野毒感染引起的生长迟缓，也可预防REV引起的对NDV和AIV灭活疫苗免疫反应的抑制作用。在1日龄攻毒REV后，有REV母源抗体组对所有三种灭活疫苗免疫后的抗体水平都显著高于无母源抗体组。免疫后4周，有母源抗体组和无母源抗体组对NDV、AIV-H9和AIV-H5的血凝抑制（HI）抗体滴度分别是3.36±2.04 vs 1.58±1.69(P＜0.01)，6.27±3.87 vs 0.71±1.60(P＜0.01)和6.72±3.92 vs 0.54±1.44(P＜0.01)。来自免疫种鸡的REV母源抗体不仅有效地预防雏鸡感染REV，而且有效地预防或减弱REV感染造成的生长迟缓及其对NDV和AIV灭活疫苗免疫后抗体反应的抑制作用。

English. The study looked at breeder chickens vaccinated with the reticuloendotheliosis virus (REV) and immunity against the REV infection. One-day-old chicks with or without anti-REV maternal antibodies were inoculated with REV. A comparison was made to judge the growth rates and antibody titers to the Newcastle disease virus (NDV) and avian influenza virus (AIV) after vaccination.This study indicated that reticuloendotheliosis virus (REV) infection caused growth retardation and severely inhibited immune reactions to inactivated vaccines against the Newcastle disease virus (NDV) and Avian influenza virus (AIV, H9 and H5) in 1-day-old broilers without maternal antibodies specific to REV. Maternal antibody of breeders vaccinated with an attenuated REV vaccine effectively protected REV-challenged birds from growth retardation and immunosuppression. This showed for antibody reactions to NDV and AIV vaccines. Four weeks after vaccination, the HI titers to NDV、AIV-H9和AIV-H5 in maternal antibody positive and negative groups were 3.36±2.04 vs 1.58±1.69(P 0.01)，6.27±3.87 vs 0.71±1.60(P0.01) and 6.72±3.92 vs 0.54±1.44(P 0.01). Maternal antibodies from breeders vaccinated with REV vaccine could successfully protect chicks from REV infection and effectively prevent growth retardation and immunosuppression in antibody responses to NDV and AIV induced after inoculation of REV.