EN
Post-mortem examinations in 2608 cows from 6 voivodeships revealed in 218 of them the presence of thelasiosis caused by Thelazia rhodesi, T. gulosa and T. skrjabini. Most animals (172) showed monospecific, the remaining ones-mixed bispecific invasions. Pathologic picture of animals is given and conclusions are drawn as to the correlation between the invasion intensity and the age of host.