Partição da energia em ovinos deslanados submetidos a três níveis de alimentação

Abstract

The aim of this study was to determine the energy partition in hair sheep fed three levels of feed (maintenance, intermediate and high). For energy partitioning a dataset with 114 individual records (54 non-castrated males and 60 females) comprising information from four comparative slaughter studies in which the measurements of gross energy intake (GEI), digestible energy intake (DEI), metabolizable energy intake (MEI), fecal, urinary and gas energy losses and determination of retained energy. GEI was higher (P < 0.05) in levels intermediate and high (3,964 and 4,872 Mcal/day, respectively) compared to maintenance (1,706 Mcal/day). The higher losses were through the fecal component, being significant for levels above maintenance (P < 0.05) recording for levels intermediate and high the values of 5,531 and 1,863 Mcal/day, respectively. At both levels above maintenance there were no differences (P > 0.05) for daily urine energy loss (Mcal/day), with mean values of (0,094 Mcal/day), however lower (P < 0.05) in animals fed at maintenance level (0,046 Mcal/day). Gas losses were greatest (P < 0.05) for animals fed at maintenance level (7.92% of GEI), followed by 7.73 and 7.65% for levels intermediate and high, respectively. The variations of energy losses in the urine were 2.64, 2.06, and 2.08% fecal losses of 34.37, 37.80, and 36.91% for maintenance intermediate and high levels, respectively. With the present study it was possible to conclude that the levels of feeding in maintenance, intermediate and high level of intake influence the partition and consequently the energy used for the animal to deposit tissues and grow. From the knowledge of the energy partition of tropical diets, it was possible to verify that the most significant energy losses occur mainly by the fecal component followed by gas losses.