1Eastern Oregon Agricultural Research Center,Oregon State University,Burns,OR 97720,USA.
3Range Cattle Research and Education Center,University of Florida,Ona,FL 33865,USA.
Animal. 2018 Aug;12(8):1576-1583. doi: 10.1017/S1751731117003585. Epub 2017 Dec 26.
This experiment evaluated the impacts of supplementing a yeast-derived product (Celmanax; Church & Dwight Co., Inc., Princeton, NJ, USA) on productive and health responses of beef steers, and was divided into a preconditioning (days 4 to 30) and feedlot receiving phase (days 31 to 69). In all, 84 Angus × Hereford steers were weaned on day 0 (BW=245±2 kg; age=186±2 days), and maintained in a single group from days 0 to 3. On day 4, steers were allocated according to weaning BW and age to a 21-pen drylot (4 steers/pen). Pens were randomly assigned to (n=7 pens/treatment): (1) no Celmanax supplementation during the study, (2) Celmanax supplementation (14 g/steer daily; as-fed) from days 14 to 69 or (3) Celmanax supplementation (14 g/steer daily; as-fed) from days 31 to 69. Steers had free-choice access to grass-alfalfa hay, and were also offered a corn-based concentrate beginning on day 14. Celmanax was mixed daily with the concentrate. On day 30, steers were road-transported for 1500 km (24 h). On day 31, steers returned to their original pens for the 38-day feedlot receiving. Shrunk BW was recorded on days 4, 31 and 70. Feed intake was evaluated daily (days 14 to 69). Steers were observed daily (days 4 to 69) for bovine respiratory disease (BRD) signs. Blood samples were collected on days 14, 30, 31, 33, 35, 40, 45, 54 and 69, and analyzed for plasma cortisol, haptoglobin, IGF-I, and serum fatty acids. Preconditioning results were analyzed by comparing pens that received (CELM) or not (CONPC) Celmanax during the preconditioning phase. Feedlot receiving results were analyzed by comparing pens that received Celmanax from days 14 to 69 (CELPREC), days 31 to 69 (CELRECV) or no Celmanax supplementation (CON). During preconditioning, BRD incidence was less (P=0.03) in CELM v. CONPC. During feedlot receiving, average daily gain (ADG) (P=0.07) and feed efficiency (P=0.08) tended to be greater in CELPREC and CELRECV v. CON, whereas dry matter intake was similar (P⩾0.29) among treatments. No other treatment effects were detected (P⩾0.20). Collectively, Celmanax supplementation reduced BRD incidence during the 30-day preconditioning. Moreover, supplementing Celmanax tended to improve ADG and feed efficiency during the 38-day feedlot receiving, independently of whether supplementation began during preconditioning or after feedlot entry. These results suggest that Celmanax supplementation benefits preconditioning health and feedlot receiving performance in beef cattle.
本试验评估了补充酵母源产品（Celmanax；Church & Dwight Co.，Inc.，新泽西州普林斯顿）对肉牛生产性能和健康的影响，分为预饲期（第 4 天至 30 天）和肥育期（第 31 天至 69 天）。共有 84 头安格斯×海福特牛犊于第 0 天断奶（BW=245±2kg；age=186±2 天），从第 0 天到第 3 天，所有牛犊均在单个组中饲养。第 4 天，根据断奶 BW 和年龄，将牛犊分配到 21 个干栏（4 头/栏）。每个栏（n=7 个处理/栏）随机分配以下处理：（1）研究期间不补充 Celmanax；（2）从第 14 天到第 69 天每天补充 Celmanax（14g/头；实际采食量）；（3）从第 31 天到第 69 天每天补充 Celmanax（14g/头；实际采食量）。牛犊自由采食干草-苜蓿干草，并从第 14 天开始提供玉米基础浓缩饲料。Celmanax 每天与浓缩饲料混合。第 30 天，牛犊被运输 1500 公里（24 小时）。第 31 天，牛犊返回其原始栏进行 38 天的肥育期。记录第 4 天、第 31 天和第 70 天的收缩 BW。第 14 天至第 69 天每天评估采食量。第 4 天至第 69 天每天观察牛的呼吸疾病（BRD）症状。第 14、30、31、33、35、40、45、54 和 69 天采集血液样本，并分析血浆皮质醇、触珠蛋白、IGF-I 和血清脂肪酸。通过比较预饲期接受（CELM）或不接受（CONPC）Celmanax 的栏来分析预饲期的结果。通过比较从第 14 天到第 69 天（CELPREC）、第 31 天到第 69 天（CELRECV）或不补充 Celmanax（CON）的栏来分析肥育期的结果。在预饲期，CELM 组的 BRD 发病率低于 CONPC 组（P=0.03）。在肥育期，CELPREC 和 CELRECV 组的平均日增重（ADG）（P=0.07）和饲料效率（P=0.08）趋于更高，而干物质采食量在处理之间相似（P≥0.29）。未检测到其他处理效应（P≥0.20）。综上所述，在 30 天的预饲期内，补充 Celmanax 可降低 BRD 发病率。此外，在 38 天的肥育期内，补充 Celmanax 可改善 ADG 和饲料效率，而与预饲期或肥育期开始时补充 Celmanax 无关。这些结果表明，在肉牛中，补充 Celmanax 有益于预饲期健康和肥育期生产性能。
