Lymphomas in poultry are common and have economic relevance due to associated mortality , condemnation as well as poor performances. Most of the lymphomas in poultry have a viral etiology and these diseases are caused by either a herpes virus as Marek’s disease ( MDV ), or by a retrovirus, leukosis/sarcoma group (ALV ), reticuloendotheliosis (REV ) and lymphoproliferative disease of turkeys .An accurate diagnosis is very important as control measures differ depending on the etiology of the lymphomas. In some cases, a specific diagnosis is needed to determine liability for losses. Это и многое другое вы найдете в книге Clinicopathological Studies On Some Neoplasms In Chickens (Doaa Hosney Assar)