Influence of lipid sources on rearing and finishing systems of beef catle

Abstract

The increase on energy density in a diet, through lipid supplementation is a nutritional strategy that can be used in cattle fattening, performing satisfactory results. The objective in this trial will be evaluate the effects of different lipid sources on performance, intake, digestibility, carcass characteristics, microbial populations, ruminal fermentation and enteric methane production in nelore steers, from rearing to finishing phase in feedlot and grazing systems. The experiment 1, rearing of animals, will be developed from august/2009 to March/2010. Will be tested the following lipid sources: linseed oil, palm oil, soy bean grain and megalac-E. Ninety animals will be used, divided into 10 paddocks (two replicates of paddocks) receiving supplementation of 0.5% body weight during the dry and rainy seasons, distributed on a randomized block design with repeated measures over time (months of the year) with 16 replications. In April/2010 these animals will be divided into two termination systems: 45 animals will be finished on pasture (experiment 2) and the remaining 45 will be kept on feedlot (experiment 3). (AU)