EN
Bacteria from genera Chlamydia (Ch.) and Chlamydophila (Chi.) are very pathogenic and may infect humans and animals. They also may cause latent infection, especially in animals. In this paper we discuss the non-specific and specific cellular and humoral immunity in farm animals, after infection or immunisation with Chlamydia sp. and Chlamydophila sp. bacteria. It has been shown, that the infection or immunisation with the microorganisms influenced the activity of polimorphonuclear cells (PMN) and mononuclear cells (MN) in the process of phagocytosis. It has also been shown that the bacteria influenced the amount and activity of lysozyme, activities of myeloperoxidase and lysosomal enzymes. Infection or immunisation with the microorganisms was demonstrated to affect numbers of lymphocytes T and B and those of their subpopulation as well as the activity of cytokines and levels of scrum and secreted immunoglobulins. The changes were detected just a few hours after infection or immunisation and persisted for a few days to a few decades.