Effects of high-level chromium methionine supplementation in lambs fed a corn-based diet on the carcass characteristics and chemical composition of the longissimus muscle

Abstract

Twenty-four male lambs (24.93 ± 0.93 kg) were used in order to evaluate the effects of chromium methionine (Cr) supplementation in high-energy finishing diets on the carcass characteristics and chemical composition of the longissimus muscle (LM). Treatments were 0.00, 0.60, 1.20, and 1.80 mg Cr/lamb daily. The experiment lasted 56 days. There were no effects of treatments on dry matter intake, feed to gain ratio, and final weight, which averaged 35.24 ± 1.01 kg. Supplemental Cr linearly decreased fat thickness enough to improve the estimated yield grade from 1.82 to 1.42 with no effect on the other carcass traits measured. Fat concentration in the LM decreased linearly as the level of Cr increased in diets, but protein concentration remain constant and so the protein/fat ratio in the LM increased. It is concluded that Cr supplementation has a modulating effect on carcasses by reducing fat; maximal response was reached at a daily dose of 1.80 mg Cr/head.