Influence of rumen non-degradable protein supplementation on intake, metabolism and performance in Nelore cattle grazing on pasture

Abstract

Supplementation in the rearing phase with rumen non-degradable protein source (RUP) may be an important strategy to address forage nutrient deficiencies and to increase the amino acid utilization efficiency and performance of animals maintained on pasture during the water period. The objective of this study was to evaluate the influence of supplementation or not with RUP on the intake, nutrient digestibility, performance (Experiment 1) and metabolism (Experiment 2) of Nellore cattle, recently weaned and kept in Brachiaria brizantha cv. During the period of the waters. For experiment 1, 80 animals with an average of 230 kg of PC were used in a completely randomized experimental design with 2 treatments (T1: animals in pasture receiving only common mineral salt (SM); T2: Animals supplemented with 0.3% PC with RUP source). The animals will be distributed in 10 paddocks of 1.8 ha, the experimental unit being the picket (5 paddocks per treatment with 8 animals each picket). Experiment 2 will be used 8 Nellore bulls, castrated, cannulated in the rumen and duodenum, arranged in four simultaneous Latin squares (2x2), to evaluate the animal metabolism and efficiency of microbial protein synthesis. The data will be analyzed using the PROC MIXED procedure of SAS and the means will be compared using the Tukey test. (AU)