PANCREATITIS CAUSED BY REOVIRUS IN GUINEA -POULTS .2.

Approx. 5% deaths were observed in guinea-poults kept under extensive conditions in groups of 10 000 at the age of 8 to 22 days. Reovirus wa s isolated from the affected poults and the disease was reproduced by the virus. Faintness, anorexia, weakness and later on laying on, opist hotonus, sporadically also spasms were observed in the poults diseased under natural conditions and after experimental infection. A part of survivals showed less intensive development and significant reduction of body mass. During the acute phase of the disease, the pancreas was enlarged by two to five times, it showed a bright yellow colour, it ha d a tense touching and haemorrhages as well as necrotic areas were fou nd in and on it. The light and electron microscopic examinations revea led degeneration and necrosis mainly in the secretory cells of the exo crine glands secreting the digestive enzymes. Active and mass multipli cation of icosahedral virions with a diameter of 66 to 72 nm was found in the cytoplasm of these cells together with a secondary dystrophy a nd lysis of cell organells (Figs 2 to 5). During the subacute phase, i rreversible loss of glandular substance and reparative processes were seen. Activity of amilase, trypsin, total protease and lipase enzymes decreased significantly in the intestinal content of infected animals. Simultaneously, those activities increased in the damaged pancreatic tissues (Figs 6 to 9). De-iodinase activity of experimentally infected guinea-poults decreased significantly in the liver parallel with the T3 and T4 levels of blood serum (Figs 10 to 12). Results of biochemica l investigations were compared to those observed earlier in case of ma labsorption syndrome of chickens. The isolated virus - according to it s morphological, physico-chemical and other characteristics - could be classified as a reovirus.