Gross and histopathological heart lesions of lymphoproliferative diseases (LPDS) in commercial layer chicken

Abstract

A total of 155 suspected cases of lymphoproliferative diseases (LPDs) like Marek’s Disease (MD), Lymphoid Leucosis (LL) and Avian Reticuloendotheliosis virus (REV) from 25 commercial layer chicken farms were studied in and around Namakkal District and Thalaivasal (Salem District). The age groups affected for MD affected heart was 36 to 55 wks., LL was 45 to 62 wks and REV was 58 to 70 wks respectively. Grossly LPDs affected heart showed misshapened with greyish myocardium in one case and misshapened with greyish areas in the right ventricle in another case respectively. Histopathological lesions of MD affected heart showed multifocal mild, moderate and severe pleomorphic lymphoid cell (PLC) infiltration in the myocardium or epicardium, focal mild monomorphic lymphoid cell (MLC) infiltration in the myocardium and patchy moderate reticular cell (RE) infiltration in the epicardium which is suggestive of lymphoproliferative diseases like MD, LL and REV.