[The first occurrence of demodicosis in cattle in Czechoslovakia].

Demodectic lesions were found in 37 per cent out of the total number of seventy-five cows examined by palpation in a large cow-house in South Bohemia, Czechoslovakia. These lesions were intradermal nodules, mostly 2 to 6 mm in diameter, located in the corium in the anterior parts of the body. The animals had 1 to 75 lesions (on the average 11.6). Their age was three to seven years. Their overall health condition was good and their behaviour was not affected. Microscopic examination revealed large numbers of Demodex bovis Stiles, 1892, causative agent of demodicosis, in the contents of nodules in five out of six examined animals. Histopathological changes in two nodules were characterized by inflammatory granulomatous structures containing large numbers of mites, epithelioid cells with rich, pale cytoplasm, giant cells of the foreign body type, and inflammatory infiltrates consisting mostly of lymphocytes. Fibroproduction in the contents of granulomas and along their periphery was markedly low.