Response of lambs confined receiving crude glicerin in total replacement to corn or associated with different energy sources

Abstract

This work will evaluate the inclusion of crude glycerin in the diet of feedlot lambs in total replacement to corn or associated with different energy sources on performance, digestibility, ruminal fermentation, blood parameters, feeding behavior, carcass traits and meat quality. In the first experiment, forty intact male lambs Santa Ines with initial body weight of 20 kg. These animals will be confined and fed with five isonitrogenous and isocaloric diets, which consist of the inclusion of glycerin in the proportions: 0%, 7.5%, 15 %, 22% and 30% DM, replacing the corn. The proportion of concentrate: roughage will be about 82:18. The experiment will evaluate the performance of 20 to 35 kg, apparent digestibility of dry matter and nutrients, blood parameters, feeding behavior, carcass traits and meat quality. This experiment will be a randomized block design with five treatments with eight replicates per treatment. Additionally to experiment 1, there will be assessment fermentative parameters of diets through ruminal pH, ammonia, short chain fatty acids, methane production, yield and quality of microbial mass. For evaluation these parameters will be used five lambs cannulated in the rumen in a 5 x 5 latin square design. In the second experiment will be assessed the association high amount crude glycerin in the diet (30% DM) with three different energy sources (corn starch, corn or cottonseed). Thirty-nine intact male lambs Santa Ines with initial body weight of 20 kg will be confined until reach 35 kg of body weight, which will be evaluated performance, apparent digestibility of dry matter and nutrients, blood parameters, carcass traits and meat quality. The diets will be isonitrogenous and isocaloric with respect concentrate: roughage 70:30. For the evaluation of fermentative parameters (ruminal pH, ammonia, short chain fatty acids, methane production) will be used nine rumen cannulated lambs in a triple 3 x 3 latin square design. In the first experiment, the results will be compared to orthogonal contrasts (P <0.05), using the PROC MIXED of SAS, and in the second experiment the results will be analyzed using PROC GLM of SAS and compared to Tukey test (P <0.05). (AU)