Cold-pressed sunflower cake (CPSC) is a cheap by-product of oil-manufacturing. Supplementing diets with CPSC, rich in fat and linoleic acid, could be an effective tool for increasing healthy fatty acids (FA) in milk. To test this hypothesis, 10 cows were used in a crossover design with two experimental diets fed during two 63-day periods. Cows' milk production was recorded and samples were taken for fat, protein, lactose, and for FA composition analysis. Dry matter intake (DMI) and dry matter apparent digestibility (DMD) were estimated using two markers. Milk acceptance test was carried out. CPSC decreased milk C12:0 (10%, p = 0.023) and C16:0 (5%, p = 0.035) and increased C18:1 cis-12 (37%, p = 0.006), C18:1 trans-11 (32%, p = 0.005), C18:2 cis-9 cis-12 (13%, p = 0.004), and cis-9 trans-11 CLA (35%, p = 0.004). CPSC increased total trans-monounsaturated FA (21%, p = 0.003), total CLA (31%, p = 0.007), and PUFA:SFA ratio (18%, p = 0.006). CPSC did not affect milk production, DMD, DMI and milk composition, but reduced fat yield (9%, p = 0.013) and FCM (7%, p = 0.013). CPSC improved milk overall acceptability. In conclusion, CPSC could modify milk FA profile without a detrimental effect on digestibility, production performance, or milk acceptance.
Keywords: alternative feedstuffs; cattle; conjugated linoleic acid; fat; oilseed.