Feed intake, nutrient digestibility, milk production and composition in dairy cows fed silage of wet brewers grain

Abstract

The aim of this study was to evaluate the supply of wet brewers grain silage with and without nutrient additives in ensiling (wheat bran, soybeans hulls and ground corn), and the effect of additives on the intake and digestibility of dry matter and nutrients as well as the efficiency, production and milk composition of Holstein cows. Four multiparous Holstein cows were used, with an average milk production of 25 liters per day. The cows were randomly assigned, via the Latin Square design (4x4), to one of four experimental diets. The experimental period was 21 days. The results obtained in the experiment were evaluated by analysis of variance, Fisher’s F test and Tukey’s test at 5 % probability. The experimental diets consisted of wet brewers grain silage alone, and this silage with the addition of wheat bran, soybean hulls or ground corn. The diets did not affect the initial body weight of the animals. Diets containing wheat bran and ground corn provided a higher intake of dry matter (21.78 and 21.50 kg day-1) and organic matter (20.42 and 20.22 kg day-1) compared to the wet brewers grain silage alone and the diet containing soybean hulls. The results observed for dry matter (636.96 and 632.96 g kg-1), organic matter (659.16 and 654.35 g kg-1 DM), crude protein (712.84 and 717.79 g kg-1 DM) and neutral detergent fiber (598.99 and 538.90 g kg-1 DM) when cows were fed diets containing soybean hulls and ground corn, respectively, were higher than other diets. The different diets did not change daily milk production, milk production corrected for 3.5 % fat or milk composition. The milk urea nitrogen from cows fed ground corn diets was a lower concentration (17.67 mg dL-1), however, it was still above the suitable range (10 to 14 mg dL-1). Providing wet brewers grain silage with soybeans hulls or ground corn to Holstein cows increased the digestibility of dry matter and nutrients. However, the use of silages with wheat bran, soybean hulls or ground corn did not alter the efficiency, production or milk composition of cows fed with these silages.