Changes in fatty acid profiles of transition milk of Czech Fleckvieh cows milked in automatic milking system

Transition milk is an important part of a newborn calf's nutrition, and its positive effects on the calf's health could be attributed, among others, to its fatty acid (FA) profile. Transition milk can be collected via automated milking systems (AMS). This study aimed to evaluate changes in FA profile of transition milk in dependence on parity, the number of milkings, and the between-milking interval when using AMS for its collection. The on-farm observation was conducted on 18 Czech Fleckvieh cows in a confined system that were in their first (7 cows), second (5 cows), or third or higher parity (6 cows). Starting from the second milking, cows were milked in AMS. Milk was sampled at each milking within 4 days postpartum and analysed for its FA profile using two-dimensional gas chromatography with a vacuum ultraviolet detector. The FA profile changed gradually with the increasing number of milkings postpartum. The relative content of short-chain and long-chain FA increased ( P < 0.05) at the expense of medium-chain FA, and the content of monounsaturated FA increased at the expense of saturated FA ( P < 0.001). Parity affected mainly the content of butyric, myristic, stearic, and oleic acids ( P < 0.05). The interval between milkings did not have a pronounced effect on the FA profile, as only slight changes in the concentration of lauric and linolelaidic acids were observed ( P < 0.05). When using AMS, cows’ parity and milking number seem to be the main factors influencing the FA profile of transition milk.