The efficacy of unspecific and specific immune responses decides on the dev
elopment of dermatomycoses in domestic animals. Phagocytosis is the main un
specific factor that eliminates invasive fungi. In natural resistance to my
coses are also active nonimmunological humoral molecules such as {alfa}-mak
roglobulin, transferin, complement system. There are three basic mechanisms
by which specific immune responses combat fungal infections. These are T c
ell-mediated mechanisms, the skin immune system and the killing of mycelium
, by,bodies. T cell primarily function in fungal infections by activating m
acrophages and by promoting epidermal growth and keratinization. Chronic an
d progressive fungal disease is associated with defects in the T cell etv,
activation of Th2 cells, modulation of immune reactions by circulating anti
bodies or antigens and with immunosuppression by fungal mannans.