EN
Dynamic and activity of myeloperoxidase and serum lysozyme, globulins, total protein in the polar blue foxes infected naturaly with the distemper virus (CDV) was examined. The two step examinations were done. In the first step the value and activity of the above mentioned parameters of unspecific humoral immunity was registered twice in 24 sick and 22 healthy foxes during sickness and just before death. In the second step the examinations were performed on 10 healthy and 12 sick foxes at the day 1, 4, 7, 10 and 13 of the disease e. g. from the appearance of the first clinical signs up to the death of the examined animals. Clinical observations, anatomopathological and virological (direct immunofluorescence test using a conjugate prepared by the Biowet Nitra, Czechoslovakia) tests were performed simultaneously with immunological tests. A complex evaluation of breeding system on 5 farms at the first step and on 3 farms at the second step of studies was also done. It was found that the natural infection of foxes with CDV increases the activity of myeloperoxidase and blood serum lysozyme and decreases the level of serum globulins.