Performance of feedlot cattle with inclusion of live yeast in the diet

Abstract

The objective of this study was to evaluate the productive performance, ingestive behavior, apparent digestibility of the diet, rectal temperature, superficial thermography of skin and hull, and the carcass traits of heifers finished in confinement under the effect of inclusion of live yeasts (Saccharomyces cerevisiae as probiotic) in the diet. The treatments were: Control: diet without the inclusion of live yeasts, and Yeast: diet with the inclusion of live yeasts (7 g animal day-1, at the concentration of 107 CFU g-1). The diets were composed of corn silage at a constant forage: concentrate ratio of 50: 50, on a dry matter basis. The experimental design was completely randomized, composed of two treatments and nine replicates, wherein each replicate was represented by a stall with two animals. Thirty-six heifers, 1/2 blood Angus, from the same herd, with an average age of 11.9 months and an initial average body weight of 317 kg, were used in the experiment. Supplementation of live yeasts in the diet for finishing heifers proved to be efficient in the feedlot finishing phase because it provided improvement in the apparent digestibility of DM. In relation to the productive performance, ingestive behavior, rectal temperature, superficial thermography of skin and hull and carcass traits, no statistical difference was found between the treatments. The animals have already come from the property adapted to the feedlot system, defining small challenge against the presence of live yeasts included in the experimental diet, justifying the lack of expression on some results obtained.