Department of Animal Science, Texas A&M University, College Station, TX 77843, USA.
J Anim Sci. 2024 Jan 3;102. doi: 10.1093/jas/skae221.
This experiment evaluated health, physiological, and performance responses of high-risk cattle administered the maternal bovine appeasing substance (mBAS) during feedlot receiving. Angus-influenced, newly weaned male calves (n = 120) were purchased from an auction facility. Calves arrived at the research feedyard on day -1 and body weight (BW) was recorded upon arrival (199 ± 1 kg). Calves were ranked by arrival BW and received 1 of 2 treatments prior to initial processing (day 0): (1) 10 mL of an mBAS (Ferappease; FERA Diagnostics and Biologicals; College Station, TX) or (2) 10 mL of mineral oil (CON; placebo). Treatments were applied topically to the nuchal skin area (5 mL) and above the muzzle (5 mL). Calves were vaccinated against Clostridium and respiratory pathogens, dewormed, implanted, band-castrated, and received metaphylaxis at initial processing, and then distributed into 10 drylot pens according to arrival BW and treatment (n = 12 calves/pen, 5 pens/treatment). Calves were reapplied treatments (mBAS or CON) concurrently with booster vaccination on d 14. Feed intake and incidence of bovine respiratory disease (BRD) were recorded daily. Blood and hair samples from the tail-switch were collected on days 0, 14, 28, 42, and 60 for analysis of physiological variables. Calves were sampled for nasal microbiota analysis via swab on days 0, 14, and 28. Final shrunk BW was recorded on day 61 after 16 h of feed and water restriction. Calf BW gain and final BW did not differ between treatments (P ≥ 0.40). Incidence of BRD was similar (P = 0.99) between mBAS and CON (56.7% for both treatments; SEM = 6.45). A greater (P = 0.04) proportion of mBAS calves diagnosed with BRD required a single antibiotic treatment to regain health (70.6 vs. 47.0%; SEM = 8.32), and mortality was greater (P = 0.03) in CON calves diagnosed with BRD (17.6 vs. 2.94%; SEM = 5.133). Relative abundance of Mycoplasma in nasal microbiota was reduced (P = 0.04) in mBAS calves compared with CON (34.7 vs. 27.4%; SEM = 2.35). Cortisol concentration in hair from the tail-switch was less (P = 0.01) on day 28 for mBAS calves compared with CON. Administering mBAS improved (P = 0.04) total pen-based liveweight change during the experiment (498 vs. 309 kg/pen; SEM = 65.2) and final pen-based total liveweight (2,676 vs. 2,484 kg/pen; SEM = 65.4). Administration of mBAS to high-risk cattle decreased physiological stress markers, reduced mortality, and increased pen-based productivity during a 60-d receiving period.
本实验评估了高危牛在牛只育肥接收期使用母牛安抚物质（mBAS）后的健康、生理和性能反应。 Angus 影响的新断奶雄性小牛（n = 120）从拍卖设施购买。小牛于第-1 天到达研究育肥场，并在到达时记录体重（BW）（199 ± 1kg）。小牛根据到达 BW 进行排名，并在初始处理前（第 0 天）接受 2 种处理之一：（1）10 mL mBAS（Ferappease；FERA Diagnostics and Biologicals；College Station，TX）或（2）10 mL 矿物油（CON；安慰剂）。处理方法是将其涂在颈背皮肤区域（5 mL）和口鼻上方（5 mL）。小牛在初始处理时接种了针对梭菌和呼吸道病原体的疫苗，驱虫，植入，去势，并用抗生素进行了预防，并根据到达 BW 和处理情况（n = 12 头/栏，5 个栏/处理）分配到 10 个干栏中。在第 14 天，小牛同时接受了增强疫苗接种和处理（mBAS 或 CON）。每天记录采食量和牛呼吸道疾病（BRD）的发病率。在第 0、14、28、42 和 60 天，从尾端的尾巴开关采集血液和毛发样本，用于分析生理变量。在第 0、14 和 28 天，通过拭子对小牛进行鼻腔微生物组分析采样。在限制 16 小时采食和饮水后，于第 61 天记录最终收缩 BW。处理之间 BW 增益和最终 BW 没有差异（P≥0.40）。BRD 的发病率在 mBAS 和 CON 之间相似（P=0.99；均为 56.7%；SEM=6.45）。更多（P=0.04）被诊断患有 BRD 的 mBAS 小牛需要单一抗生素治疗来恢复健康（70.6%对 47.0%；SEM=8.32），CON 中被诊断患有 BRD 的小牛死亡率更高（P=0.03；17.6%对 2.94%；SEM=5.133）。与 CON 相比，mBAS 中小牛鼻腔微生物组中的支原体丰度降低（P=0.04；34.7%对 27.4%；SEM=2.35）。与 CON 相比，mBAS 中小牛尾端毛发中的皮质醇浓度在第 28 天较低（P=0.01）。mBAS 的管理（P=0.04）改善了实验期间（每栏 498 公斤对 309 公斤/栏；SEM=65.2）和最终每栏总活重（2676 公斤对 2484 公斤/栏；SEM=65.4）的总栏活重变化。在 60 天的育肥期内，给高危牛施用 mBAS 可降低生理应激标志物，降低死亡率，并提高每栏的生产效率。
