Bedding Application to Feedlot Steers: Influence on Growth Performance, Estimated Maintenance Coefficient, Carcass Characteristics, and Circulating Metabolites in Beef Steers

SIMPLE SUMMARY: A sizeable portion of cattle fed in the United States are fed in the Upper Midwest and Northern Plains where winter temperatures routinely fall below freezing. Using bedding application to improve cattle comfort and performance has been a common practice in livestock production for many years. However, the exact degree to which bedding improves performance is difficult to quantify. As such, two studies were conducted to evaluate the effects of bedding use on growth performance, estimated maintenance energy requirement, carcass characteristics, sera responses in beef steers of differing ages, and phases of feedlot production. Experiment 1 showed that applying wheat straw bedding to yearling crossbred beef steers at a rate of 1.8 kg/steer·d(−1) increased feed consumption, feed efficiency, and average daily gain. In experiment 2, newly weaned calves bedded with 1.0 kg of wheat straw bedding/steer·d(−1) tended to consume 4.5% less feed and had a 5.6% improvement in feed efficiency. In both studies, the energy required for maintenance for non-bedded steers was increased. These experiments indicate that bedding application should be considered to improve growth performance and feed efficiency in beef steers by reducing maintenance energy requirements during the feedlot receiving and finishing phases. ABSTRACT: Two randomized complete block design experiments were conducted to evaluate the effect of bedding use in confined beef steers. Experiment 1 used Simmental × Angus steers (n = 240; initial body weight (BW) = 365 ± 22.5 kg). Experiment 2 used newly weaned Charolais × Red Angus steers (n = 162; initial BW = 278 ± 13.4 kg). Steers were allotted to one of two treatments: (1) no bedding (NO), or (2) 1.8 kg (Experiment 1) or 1.0 kg (Experiment 2) of wheat straw (as-is basis) bedding/steer·d(−1) (BED). In Experiment 1, applying bedding improved (p ≤ 0.01) dry matter intake (DMI), kg of gain to kg of feed (G:F), and average daily gain (ADG). Bedding reduced (p = 0.01) the estimated maintenance coefficient (MQ). Dressing percentage, rib fat, marbling, and yield grade were increased (p ≤ 0.03) in NO. Bedding resulted in an increase (p = 0.01) in serum insulin-like growth factor I (IGF-I). In Experiment 2, a tendency (p = 0.06) for increased DMI for NO was noted. Bedding improved G:F (p = 0.01). MQ was elevated (p = 0.03) for NO and NO had an increase (p = 0.02) in serum concentration of urea-N (SUN). An increase (p = 0.01) in serum non-esterified fatty acid was noted for NO. These data indicate that bedding application should be considered to improve growth performance and feed efficiency by reducing maintenance energy requirements in beef steers during the feedlot receiving and finishing phase.