EN
The aim of the study was to evaluate the changes of selected immunological parameters in seropositive cattle infected with Mycoplasma bovis. The study was performed on two age groups of cattle, i.e. young (n=139) and adult (n=21) animals. Within the each age group, two subgroups composed of seropositive and seronegative animals for M. bovis infection were formed. The serum samples were collected and the following immunological parameters were determined: Mycoplasma bovis antibodies, total protein, γ-globulins, and selected acute phase proteins - haptoglobin and serum amyloid A. In M. bovis seropositive cattle, the distinct increase in all examined parameters in both age groups was observed as compared with the controls. The results indicated the significant stimulation of immune response in the affected cattle and the performed assays confirmed the real possibility for their use in the screening diagnosis of the bacterial infections.