Abstract: | In a sheep population consisting of animals of different breeds the epidemiologic development of the Maedi-Visna-infection was evaluated by means of monthly Immune Diffusion Test (ID) for a period of 30 months. At the beginning the herd consisted of eight animals, where four of them showed clinical symptoms indicative for a MV-infection with positive serological results. The other 4 animals were negative. The herd increased in number by including the offspring and buying in other animals. During the time of 30 months only in one animal a seroconversion could be observed. In nine of 13 lambs borne of seropositive mothers colostral antibodies could be observed. By testing the colostrum of MV-seropositive mothers 6 of 7 animals showed precipitating antibodies. Positive sera showed average titers of 1:2 till 1:64, the highest titer was 1:512. On the postmortal examination of five serological positive animals which were killed because of dominant clinical symptoms, three of them showed MV-lesions partly superinfected with bacteria. In one sheep the diagnosis was pasteurellosis. On a further animal the clinical picture and the histologic results were indicative for the Visna-form of the disease. |