The objective of this study was to determine the effect of parity on the fatty acid profile of milk from 42 high-yielding cows, including 15 primiparous cows, 15 cows in their second lactation and 12 cows in their third lactation. Milk yield was evaluated and milk samples (462 in total) were collected between lactation days 6 and 60, at five-day intervals. The concentrations of 43 fatty acids were determined by gas chromatography in extracted fat. Cows in their third lactation were characterized by the highest milk yield – over 305-day lactation, they produced 13,160 kg of milk on average. Milk from primiparous cows had the most desirable fatty acid profile. It contained more (by ca. 12–17%) n-3 fatty acids and less (by 2.89–5.46%) fatty acids that adversely affect human health, compared with the other groups. Among essential fatty acids, differences were noted with respect to CLA (+9.5–9.8%), LNA (+12.7–18.7%) and DHA (+21–23%) to the advantage of the milk fat of primiparous cows.

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