Smerchek Dathan Thomas, Smith Zachary Kidd
Department of Animal Science, South Dakota State University, Brookings, SD 57007, USA.
Animals (Basel). 2020 Sep 29;10(10):1766. doi: 10.3390/ani10101766.
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 ( = 240; initial body weight (BW) = 365 ± 22.5 kg). Experiment 2 used newly weaned Charolais × Red Angus steers ( = 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 (BED). In Experiment 1, applying bedding improved ( ≤ 0.01) dry matter intake (DMI), kg of gain to kg of feed (G:F), and average daily gain (ADG). Bedding reduced ( = 0.01) the estimated maintenance coefficient (MQ). Dressing percentage, rib fat, marbling, and yield grade were increased ( ≤ 0.03) in NO. Bedding resulted in an increase ( = 0.01) in serum insulin-like growth factor I (IGF-I). In Experiment 2, a tendency ( = 0.06) for increased DMI for NO was noted. Bedding improved G:F ( = 0.01). MQ was elevated ( = 0.03) for NO and NO had an increase ( = 0.02) in serum concentration of urea-N (SUN). An increase ( = 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.
进行了两项随机完全区组设计实验，以评估在舍饲肉牛中使用垫料的效果。实验1使用西门塔尔×安格斯肉牛（n = 240；初始体重（BW）= 365±22.5千克）。实验2使用新断奶的夏洛莱×红安格斯肉牛（n = 162；初始体重 = 278±13.4千克）。肉牛被分配到两种处理之一：（1）无垫料（NO），或（2）1.8千克（实验1）或1.0千克（实验2）的麦秸（原样基础）垫料/头·天（BED）。在实验1中，使用垫料提高了（P≤0.01）干物质摄入量（DMI）、每千克饲料的增重（G:F）和平均日增重（ADG）。垫料降低了（P = 0.01）估计的维持系数（MQ）。在NO组中，屠宰率、肋部脂肪、大理石花纹和产肉等级有所提高（P≤0.03）。垫料导致血清胰岛素样生长因子I（IGF-I）增加（P = 0.01）。在实验2中，观察到NO组有DMI增加的趋势（P = 0.06）。垫料改善了G:F（P = 0.01）。NO组的MQ升高（P = 0.03），且NO组血清尿素氮（SUN）浓度增加（P = 0.02）。观察到NO组血清非酯化脂肪酸增加（P = 0.01）。这些数据表明，在育肥牛的育肥前期和后期，应考虑使用垫料，以通过降低维持能量需求来提高生长性能和饲料效率。
