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 d -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 (d 0): 1) 10 mL of a 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 d 0, 14, 28, 42, and 60 for analysis of physiological variables. Calves were sampled for nasal microbiota analysis via swab on d 0, 14, and 28. Final shrunk BW was recorded on d 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 d 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.

中文翻译：

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在 60 天的饲养场接收期内，施用母牛安抚物质可提高高风险牛的整体生产力和健康状况


该实验评估了在饲养场接收期间施用母牛安抚物质 (mBAS) 的高风险牛的健康、生理和性能反应。受安格斯影响的、新断奶的雄性小牛 (n = 120) 是从拍卖机构购买的。小牛于 d -1 到达研究饲养场，并在到达时记录体重 (BW) (199 ± 1 kg)。根据到达体重对犊牛进行排名，并在初始加工前接受 2 种治疗中的 1 种 (d 0)：1) 10 mL mBAS（Ferappease®；FERA Diagnostics and Biologicals；College Station, TX）或 2) 10 ml 矿物油（CON；安慰剂）。治疗局部应用于颈部皮肤区域（5 mL）和口吻上方（5 mL）。犊牛在初始处理时接种了梭状芽胞杆菌和呼吸道病原体疫苗，进行驱虫、植入、带状阉割和过敏治疗，然后根据到达体重和治疗情况分配到 10 个干燥栏（n = 12 头犊牛/栏，5 栏/处理） 。第 14 天，在加强疫苗接种的同时，对犊牛重新进行治疗（mBAS 或 CON）。每天记录采食量和牛呼吸道疾病 (BRD) 的发生率。在第 0、14、28、42 和 60 天收集来自尾部开关的血液和毛发样本，用于分析生理变量。在第 0、14 和 28 天，通过拭子对犊牛进行鼻腔微生物群分析。在限制饲料和饮水 16 小时后，在第 61 天记录最终缩小的体重。不同处理之间犊牛体重增加和最终体重没有差异 (P ≥ 0.40)。 mBAS 和 CON 之间的 BRD 发生率相似 (P = 0.99)（两种处理均为 56.7%；SEM = 6.45）。被诊断患有 BRD 的 mBAS 犊牛需要单一抗生素治疗才能恢复健康的比例更高（P = 0.04）（70.6% vs. 47.0%；SEM = 8。32），诊断为 BRD 的 CON 犊牛死亡率更高（P = 0.03）（17.6% vs. 2.94%；SEM = 5.133）。与 CON 相比，mBAS 犊牛鼻腔微生物群中支原体的相对丰度降低（P = 0.04）（34.7% vs. 27.4%；SEM = 2.35）。与 CON 相比，mBAS 小牛在第 28 天时尾部毛发中的皮质醇浓度较低 (P = 0.01)。施用 mBAS 改善了实验期间基于栏的总活重变化（P = 0.04）（498 与 309 公斤/栏；SEM = 65.2）和最终基于栏的总活重（2,676 与 2,484 公斤/栏；SEM = 65.4） 。在 60 天的接收期内，对高危牛施用 mBAS 可以降低生理应激标志物、降低死亡率并提高圈内生产力。