Pathomorphological and immunohistochemical investigations of myelocytoma caused by avian leukosis virus – J in adult laying birds

The subgroup J of avian leukosis virus causes myelocytomas, a neoplastic condition the birds that affects several visceral organs. In present study, myelocytomas were diagnosed in adult laying based on cytological and histopathological examination. On necropsy examination, showed enlarged liver spleen with multifocal tumorous growths liver, spleen, kidneys, lungs, ovary, proventriculus, intestine mesentery. Cytological examination impression smears from lesions revealed characteristic myeloid cell population granular cytoplasm large eccentric nucleus prominent nucleoli. Histopathologically, most organs infiltration uniform sized, cells arranged sheets or columns. These had number cytoplasmic acidophilic granules pleomorphic, vesicular lobulated few chromatin clumps. addition, mitotic figures also observed. confirmatory diagnosis was done by immunolocalization ALV-J viral antigen within infiltrating various tissues. Thus, study circulation causing myelocytomoa under field conditions Punjab, India. Further, cytopathology can be used as an alternative tool for this disease limited resources.