Blood parameters of dairy cows supplemented with different fat sources

This study was carried out to evaluate the use of different fat sources in dairy cows rations and its effects on dry matter intake, milk yield and composition, and blood parameter. Twelve Holstein cows were allocated in three balanced latin square 4x4, and fed with the following rations: 1) Control, with 2.5%; 2) Refined soybean oil; 3) Whole soybean; and 4), Calcium salts of fatty acids (Megalac-E). The concentrations of total cholesterol and lipoprotein low density (LDL) were higher (P < 0.05) for cows that received rations with fat sources, which also causes increased (P < 0.05) e concentration of high density lipoprotein (HDL). The concentrations of urea and blood urea nitrogen were similar among the rations, except for the diet containing calcium salts of fatty acids, which showed lower (P < 0.05). The dry matter intake was lower (P < 0.05) in cows that received calcium salts in the rations. The animals that received a diet containing whole soybeans as a source of fat had lower (P < 0.05) yield milk when compared to other rations used. The use of fat sources in dairy cows rations influenced the blood parameters, especially for parameters related to lipidogram.