四川省地方品种种鸡群四种垂直传播疾病血清流行病学调查OA

This study aimed to systematically evaluate the seropositivity and epidemiological characteristics of four vertically transmitted diseases—avian leukosis(AL),reticuloendotheliosis(RE),chicken infectious anemia(CA),and avian reovirus disease(AR)in local breeder chickens of Sichuan Province.Using the ELISA method,serum samples collected from seven local chicken breeds across five regions—Northwestern,Northeastern,Southern,Central,and Southwestern of Sichuan—were tested for antibodies against the four pathogens.The results showed that the four pathogens exhibited varying degrees of infection in local breeder chickens in Sichuan Province.The total antibody positivity rate was highest for ARV(78.10%),followed by CAV(55.90%)and REV(47.40%),while the ALV-J antibody positive rate was the lowest(8.12%).Among them,REV infection was the most widespread,with antibodies detected in all local breeder chicken flocks.Mixed infections with the four pathogens were severe,with dual infections being the most prevalent(36.80%),while triple(20.77%)and quadruple(1.35%)infections were also observed.The severity and patterns of mixed infections varied across different geographical regions,with Southwestern Sichuan exhibiting a triple infection rate as high as 77.50%.Susceptibility to the four pathogens differed significantly among the breeds,and risk assessment further revealed the susceptibility risks of each breed.Meihua breeding chickens showed some resistance to CAV,ARV,and REV infections,while Jiuyuan Black chickens were susceptible to ALV-J and CAV.In summary,the four vertically transmitted pathogens exhibited high infection rates and extensive dissemination among the seven local chicken breeds in Sichuan Province,with severe mixed infections.This study will provide a theoretical basis for the development and conservation of local breeder chicken resources in Sichuan Province,thereby promoting the secure and sustainable development of local breeder chickens'genetic resources.