<b>Partial replacement of soybean meal by urea and forage cactus in lactating cows diets. Digestibility</b> - DOI: 10.4025/actascianimsci.v25i2.567

Abstract

The aim of this work was to evaluate the partial replacement of the soybean meal by urea plus forage cactus on the apparent digestibility of the nutrients. Eight Holstein cows were assigned in a two (4x4) latin square design. The urea represented 0.0%, 0.8%, 1.54%, and 2.40% of dry matter (DM) of the diets, corresponding to 2.32%, 4.65%, 6.66% and 8.02% of crude protein (CP) levels in the form of non-proteic nitrogen compounds (NPN). The digestibility of the crude protein, total carbohydrates, non-fiber carbohydrates, neutral detergent fiber, and acid detergent fiber was not affected by NPN levels (75.56%; 71.36%; 89.40%; 50.61%; the 57.30%, respectively). The apparent digestibility coefficients of dry matter, organic matter and ether extract decreased lineally. The TDN values determined in digestibility trial and the estimated by NRC (2001) presented high correlation (0.91).