Performance of categories of beef cattle supplemented with concentrates in the period of draught under two forage supplies of Brachiaria brizantha

Abstract

The experiment will be conducted at APTA Regional Pole-Far West, located in Andradina-SP, in the period from February to December 2011. This work will be conducted to evaluate the effects of supply/availability of forage Brachiaria brizantha cv. Marandu, with the addition of supplementation on performance of beef cattle grazing undergoing continuous stocking during the dry season. The design is a randomized block with three replications in a 2 x 2 factorial, with two categories of beef cattle (steers and heifers) and two forage supplies, resulting in four treatments. Two forage supplies will be used, high (10 - 15 kg DM/ 100 kg BW) and average (6 - 8 kg DM/ 100 kg BW). Supplements (concentrates) are based on soybean hulls, citrus pulp and soybean meal. The protein content is consistent with the expected performance (0.7 kg / day), supplemented with 0.7% of body weight. 36 steers will be used Guzera in the growing phase, with initial weight of 320 kg and about 18 months old, an experimental period divided into five periods of 28 days during the dry season (July-October). Laboratory tests will be conducted at the Laboratory of Forage and Food Science of UNESP, Dracena. The data will be analyzed statistically using the program R (R Development Core Team, 2006) for the statistical analysis of variance and Tukey test at a significance level of 5%.