Sunflower oil supplementation in the diets of lactating cows: productive and nutritional performance

Eight Jersey cows (2nd-4th lactation; 483 ± 43 kg body weight; milk yield 21±2.2 kg day-1) were used in a double 4x4 latin square design to evaluate whether the inclusion of increasing levels of sunflower oil in the concentrate up to the limit of 110.0 g kg-1 DM of EE, in replacement to corn grain, has an impact on milk production and composition, feed efficiency, energy balance, intake and digestibility. of diets, and the fatty acid profile of milk fat from Jersey cows. The treatments consisted in lipid supplementation with increasing levels of sunflower oil replacing the corn grain and wheat bran of concentrate, including: CD (control diet), without sunflower oil and with 38 g kg-1 of EE dry matter (DM); and three treatmens with sunflower oil concentrate-included: SF65= 65 g kg-1 DM of EE; SF86=86 g kg-1 DM of EE and SF110=110 g kg-1 DM of EE. The increase of EE in diets did not affect the dry matter intake, neutral detergent fiber or crude protein. There was a linear increase in the digestibility coefficients for organic matter, crude protein, EE, neutral detergent fiber and blood levels of cholesterol. Treatments did not affect milk production, fat content, lactose or total solids. It is possible to use up to a limit of 110.0 g kg-1 DM of EE in the diet, decreasing the concentrate total amount.