Sero-prevalence and pathological examination of lymphoid leukosis virus subgroup a in chickens in Anhui Province,China

The avian lymphoid leukosis is caused by various avian retroviruses which induce a variety of benign and malignant neoplasm in domestic chickens with subsequent economic losses to poultry industry. effected birds show lymphocyte tumor,abnormal proliferation and series of tumors in connective tissues and other visceral organs. to evaluate the status of lymphoid leukosis virus subgroup a (alv-a) infection in freerange chickens in five different cities of anhui province,a total of 732 serum samples were analyzed through enzyme-linked immuno sorbent assay (elisa) in 2015 and 2016. the diagnosis of avian leukosis virus subgroup a (alv-a) infection was confirmed by necropsy,histopathological examinations and pcr analysis. the results showed,20 chickens as positive for alv-a (2.73%,95% ci 1.7-4.2) and these chickens were found to be positive for alv-a with the further distribution of 2.91% (95% ci 1.0-6.7),3.70% (95% ci 1.5-7.5),2.48% (95% ci 0.5-7.1),3.13% (95% ci 0.6-8.9) and 1.30% (95% ci 0.2-4.6) in anhui province of huaibei,suzhou,bozhou,bengbu and fuyang,respectively. the present survey showed that free-ranging chickens of anhui province have been exposed to lymphoid leukosis virus subgroup a,indicating a high risk factor for poultry industry. copyright 2017 zoological society of pakistan.