EN
Investigations were conducted on the level of fatty acids in the livers of young and old cattle infected with Fasciola hepatica. Group I constituted livers with insignificantly thickened bile ducts; group II - livers with significantly thickened bile ducts, focuses of calcification and parenchymatouse degeneration of the liver; group III - livers with calcified bile ducts, isolated abscesses and lipids degeneration of the liver. Livers without invasion of Fasciola hepatica served as a control group. Sixteen fatty acids were determined in the livers: 5 saturated acids (C14:0, C15:0, C17:0, C18:0, C16:0), 6 essential unsaturated fatty acids (C18:2, C18:3, C20:2, C20:3, C20:4, C22:6), as well as 5 other unsaturated fatty acids (C14:1, C16:1, C17:1, C18:1, C20:l). Changes in the fatty acid level depended on the age of the investigated cattle. In the livers of young cattle a statistically significant (p< 0.05) increase in the level of the margaroleic acid (C17:1) was observed, while in older cattle there was an increase in the levels of the following acids: palmitic acid (C16:0), myristic acid (C14:0), margaroleic acid (C17:1), as well as a decrease in the levels of stearic acid (C18:0), pentadecanoic acid (C15:0) and linoleic acid (C18:2).