Abstract

Marekʼs disease, a Herpesvirus-induced lymphoproliferative disease, is known to affect chickens and other domesticated and wild birds.One of the five green peafowls (Pavomuticus) in the owner’s collection had already died. The affected bird showed non-specific clinical signs such as depression, weight loss and anorexia. At necropsy, the liver and spleen were observed diffuse enlargement accompanied by several times the normal size with white to gray in color and firm, and the cut surface was smooth. Grossly, the other visceral organs were normal. Histopathological and immunohistochemical examination were done for the affected tissues. Diffuse infiltration of the liver and spleen caused loss of normal architecture.Tumor cells are characterized by large, pleomorphic nuclei with prominent nucleoli. According to immunohistochemical findings, the majority of transformed T cells expressed CD4-/ CD8+.In addition, the immunohistochemistry for CD30 were positive. In PCR, MDV was detected by specific primers. To our knowledge, this is the first report of Marek’s disease in peafowls (Pavomuticus) which were infected naturally and had thought is refractory to this infection.

Keywords: Marekʼs disease;Herpesvirus;Green peafowl; Lymphoma; Tumor cells

Abbreviations: IHC: ImmunoHistoChemical; ICTV: International Committee on Taxonomy of Viruses;MDV: Marek’s Disease Viruses; NK: Natural killer