Abstract
Two trials will be conducted to evaluate the effects of glycerol (crude glycerin) in diets of feedlot as ingredient able to reduce nutritional metabolic disorders in total or partial replacement of corn. In experiment 1, we will analyze the adptation period, performance and feeding behavior. Sixty three lambs will be used (½ Santa Inês × ½ Dorper), which will be divided by weight in a complete randomized block design and subjected to four experimental diets containing 0, 10, 20, or 30% crude glycerin, on dry matter. During adaptation period, 15 animals will be slaughtered (3 at the beginning and 12 after the adaptation, 3 per treatment) to evaluate the rumen health and morphometry of papillaes. The other animals (n = 48) will remain in feedlot until they gain 35 kg BW and then slaughtered for evaluation of carcasses, rumen health and the morphometry of papillaes. In the second trial, eight sheep fitted with permanent rumen cannulas will be used, which will serve as donors of rumen fluid for "in vitro" production of greenhouse gases, pH, SCFA, NH3-N, digestibility, as well as for incubations on the occasion of ruminal degradability trial. The data from the first trial will be assessed linear and quadratic effects of the inclusion of crude glycerin and the contrast between the control treatment × treatments crude glycerin. In experiment 2, the data will be evaluated on Latin square 4 × 4 and repeated measures will be used. In all trials, the MIXED procedure of SAS statistical software will be used considering a significance of 5% and a tendency of 10%. (AU)
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