Nutrition of lambs with chromium propionate and its effects on metabolism, performance and meat quality

This study aimed to evaluate the effects of two additional doses of chromium propionate on performance, carcass characteristics and meat quality, bone density and metabolites. A total of 29 uncastrated male lambs were divided into 3 treatments: CTL, no chromium added; Cr0.5, 0.5 mg/kg of DM; and Cr1.5, 1.5 mg/kg of DM. The experimental period lasted for 64 days during which blood samples were taken for biochemical analysis, the animals were weighed for performance evaluation, and individual and daily feed consumption were monitored. At slaughter, data were collected to evaluate carcass and meat characteristics, viscera, and femur weight for bone density. The experimental design was completely randomized with means compared by the Tukey test at 5 % probability. The inclusion of chromium propionate increased dry matter intake (P<0.0001), decreased feed efficiency (P=0.0002), and increased Cr concentration in the meat (P=0.0341). The cholesterol (P=0.0023) and phosphorus (P=0.0213) were lower in Cr0.5, and alkaline phosphatase decreased linearly (P=0.0274). Cr improved the parameters of total leukocytes (P=0.0126), lymphocytes (P=0.0476), and monocytes (P = 0.0058). No effect of Cr was observed on carcass characteristics, commercial cuts, meat quality, viscera, and femur density. Supplementation with 0.5 mg of chromium propionate positively affected the immune system of lambs in feedlots, increasing the amount of chromium in the meat. However, above this amount may reduce dry matter intake and feed efficiency.