Performance, carcass characteristics, and meat quality of lambs fed diets containing crude glycerin

Abstract

The aim of this study was to evaluate the effects of four crude glycerin levels in the diet of feedlot lambs on performance, carcass characteristics, and meat quality. Forty three-month-old crossbred Santa Inês x Dorper lambs weighing 18.2 ± 0.169 kg were used in a completely randomized design, with four diets and 10 replicates per diet. The animals were housed in individual pens. The trial period (42 days) was preceded by 14 days of adaptation to handling and diet. Final body weight (FBW), empty body weight (EBW), average daily weight gain, feed conversion, and feed efficiency did not differ with crude glycerin levels in the diet. Nutrient intake (dry matter (DM), ether extract (EE), crude protein (CP), and neutral detergent fiber (NDF)) did not differ depending on crude glycerin levels. In the evaluation of carcass characteristics, there was a quadratic effect due to crude glycerin levels on hot carcass yield (maximum point- maxP = 9.73%), leg perimeter (maxP = 9.45%), fat thickness (maxP = 7.41%), and leg weight (maxP = 8.69%). Loin weight and conformation showed a linear increase as a function of crude glycerin levels. The other studied variables were not affected by crude glycerin levels in the diet. In the non-carcass components, the full gastrointestinal tract, mesenteric fat, omental, and perirenal fat were not influenced by crude glycerin levels. Regarding meat quality, no effects were observed on the parameters evaluated in the longissimus dorsi.  The addition of up to 15% crude glycerin in the lamb's diet does not affect its performance, however, the addition of up to 8% improves carcass characteristics and maintains meat quality.