Pathogenic effect of osteopetrosis virus strain MAV-2(0) on guinea fowl pancreas.

Osteopetrosis virus strain MAV-2(0) in guinea fowl pancreas induces early unspecific changes in separate acini and the development of neoplasia among apparently unaffected acinar tissue. The tumors were classified as serous and mucinous adenomas and adenocarcinomas, as well as poorly differentiated carcinomas. Foci of phenotypically altered acinar cells were observed in single experimental birds.

Type A oncornavirus-like particles in turkey bone marrow cells transformed by avian leukemia virus.

Type A oncornavirus-like particles (TAOLP) were found in the cytoplasm of turkey bone marrow cells transformed by strain Mc-31 avian leukemia virus. They resembled morphologically the cores of budding virions and the cores of immature extracellular Mc-31 virus particles. TAOLP were observed more often in T3Mc31 cells where cytopathological changes existed.

Virus-induced duodenal adenomas in guinea fowl.

Polypous growths of the duodenal mucosa were induced in guinea fowls after iv inoculation o virus strain Pts-56. The growths developed in about 60% of the experimental birds after a latent period of 4-6 months. The chronologic study of the alterations in the duodenal mucosa revealed consecutive occurrence of focal lymphoid cell infiltrations of the propria, restricted crypt hyperplasia, and enlargement of the villi followed by the formation of tubulovillous and tubulous adenomas.

Haematological and pathomorphological studies on chickens inoculated with transformation-defective sarcoma virus.

A transformation-defective mutant of Rous sarcoma virus (td PR-RSV-C) inoculated into chicken embryos caused a number of pathological changes in chickens after hatching. Disturbances in haematopoiesis were manifested by anaemia of different degree and by the presence of immature blood elements in the peripheral blood. The haematological picture of erythroblastosis was confirmed histologically.

Virus-induced pancreatic cancer in guinea fowl: a morphologic study.

The morphologic lesions in the pancreas of 350 guinea fowls infected with avian osteopetrosis virus strain Pts-56 were studied. Focal unspecific changes in the acinar tissue, including reduction of zymogen content, diminution of cytoplasm, and dilatation of acinar lumens accompanied with substitution of the affected acini by tubular structures lined with centroacinar-like cells, developed 2 months from post infection (p.i.