Effect of weaning strategy and backgrounding management on growth performance, carcass characteristics, and mRNA expression in the longissimus muscle of beef steers.

The intramuscular fat depot, also called marbling, is a vital component of beef quality. This study aimed to investigate the effect of the weaning strategy (early vs. normal) and the subsequent backgrounding management on marbling deposition of beef carcasses. Early weaned calves were weaned at 130 d of age and fed a grain-based diet until nursing calves were normal weaned. Steers were subsequently fed either a forage-based diet or a concentrates-based diet until finished on a high-grain diet. Growth performance parameters and mRNA expression in the longissimus muscle were measured over time. Overall, compared to normal weaning, early weaning followed by different managements during the backgrounding did not increase the marbling score of beef steers. However, early weaned steers backgrounded on a forage-based diet required fewer days on feed in the finishing phase to reach harvesting target.