[Experimental Q-rickettsiosis in lambs].

The clinical course, serologic response, and morphologic changes were followed up in month-old lambs infected nasally and via the trachea with Rickettsia burneti at the rate of 10,000 ID50/cm3. Rickettsiae were found in the parenchymal organs, the blood clot, the nasal cavity, the trachea, and the feces of the animals killed on the 7th and 21st day of infection. Complement-fixing antibodies were established in the infected lambs with the use of the complement-fixation test from the 5-6th up to the 160th day (period of testing), the highest value of the titer (1:160) being observed on the 32nd day. Demonstrated were changes in the vessels, and degeneration was found in the liver, kidneys, and other viscera along with proliferative changes in the spleen. Guinea pigs and albino mice were successfully made use of to isolate Rickettsia burneti from the infected parenchymal organs, feces, and others of affected lambs.