avian leukosis viruses (alvs) cause different types of tumours in poultry and can affect the health and egg production of the birds. to investigate the presence of the virus in chicken layer flocks in shiraz, 222 egg albumen from local layer breeder (25 eggs), local layer grand parent (30 eggs), broiler breeder (60 eggs), commercial layer (46 eggs) and broiler grand parent (61 eggs) were tested...
