Submitted to: Avian Diseases
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/1/1998
Publication Date: N/A
Citation: Interpretive Summary: Sarcomas are cancer-like conditions rarely seen in lungs of commercial chickens. Such conditions can be caused by viruses that are common in the poultry environment. We report for the first time the diagnosis of such disease condition in the lung of a commercial broiler chicken. Our investigations revealed that out of all viruses that can cause such conditions, the tissues examined were only positive for the presence of a newly emerging virus termed subgroup J avian leukosis virus, suggesting that this virus is capable of inducing such disease condition. Because this is the first report of such condition in commercial chickens, the information should be of practical significance to poultry breeders and growers and to scientists who are studying pathological conditions induced by this virus.
Technical Abstract: Both lungs of a 5 week-old broiler chicken contained miliary, round, white tumors. Microscopically, these masses were composed of compactly-arranged cells with round to oval nuclei and indistinct cytoplasmic borders. Immunohistochemically, tumor cells were positive for vimentin, but negative for cytokeratin, S-100 protein, neuron specific enolase, smooth muscle actin and muscle specific actin. Ultra structurally, tumor cells were separated by collagen bands and some contained collagen fibrils. These results suggest that the primitive mesenchymal cells composing these sarcomas may have originated from precursors of interstitial cells or fibroblasts of the interparabronchial or interatrial septa. DNA was extracted from paraffin-embedded tissues and probed for sequences specific for Marek's disease herpesvirus, reticuloendotheliosis viruses, exogenous avian leukosis viruses, and subgroup J avian leukosis viruses. Only sequences specific for subgroup J avian leukosis viruses were identified in the DNA extracted from tumors and surrounding lung.