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.

中文翻译：

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在 60 d 饲养场接收期内，施用母牛安抚物质可提高高危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） 的高危牛的健康、生理和性能反应。受安格斯影响的、新断奶的雄性犊牛 （n = 120） 是从拍卖机构购买的。犊牛在第 −1 天到达研究饲养场，到达时记录体重 （BW）（199 ± 1 公斤）。犊牛按到达 BW 排名，并在初始处理前（第 0 天）接受 2 次治疗中的 1 次：（1） 10 mL mBAS（Ferappease;FERA 诊断和生物制品;College Station， TX） 或 （2） 10 mL 矿物油（CON;安慰剂）。局部治疗应用于颈项皮肤区域 （5 mL） 和口吻上方 （5 mL）。犊牛接种梭状芽胞杆菌和呼吸道病原体疫苗，驱虫、植入、带状阉割，并在初始处理时接受过敏反应，然后根据到达体重和处理分配到 10 个干地围栏中 （n = 12 头犊牛/栏，5 个围栏/处理）。第 14 天，犊牛在加强疫苗接种的同时重新应用治疗 （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 天收集来自尾部开关的血液和头发样本，用于分析生理变量。在第 0 天、第 14 天和第 28 天通过拭子对犊牛进行鼻腔微生物群分析。在饲喂和饮水限制 16 小时后，第 61 天记录最终收缩的 BW。治疗之间的小腿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） （两种治疗为 56.7%;SEM = 6.45）。更大比例 （P = 0.04） 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 （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 犊牛在第 28 天从尾部开关获得的毛发中的皮质醇浓度较低 （P = 0.01）。在实验期间，使用 mBAS 改善了 （P = 0.04） 基于笔的总活重变化 （498 vs. 309 kg/笔;SEM = 65.2）和最终基于笔的总活重（2,676 vs. 2,484 kg/笔;SEM = 65.4）。在 60 天接受期间，对高危牛施用 mBAS 可降低生理应激标志物，降低死亡率，并提高基于围栏的生产力。