The effect of a nutraceutical mixture, based on live yeast (LY), mannan oligosaccharides (MOS) and organic selenium (Se) on health status, as well as immune functionality and growth performance in the fattening of newly received beef cattle, was evaluated. A total of 1036 Charolaise heifers were allocated into two experimental groups: (i) control group, without any nutraceutical support (n = 487; initial weight = 325 ± 21 kg); and (ii) treatment group, supplementation during the first 30 days, with LY (5 g/head/day), organic Se (3 mg/head/day), and MOS (10 g/head/day) (n = 549; initial weight = 323 ± 23 kg). The incidence of bovine respiratory disease (BRD) and other health issues was monitored, as well as the mortality rate. Blood samples were taken at d₀ and d₃₀ to evaluate the immune functionality and the inflammatory status. Growth performances, feces chemical composition, and carcass characteristics were recorded. The BRD occurrence tended to be reduced (p = 0.06) in the Treatment group. The BHV-1 antibody production after vaccination was significantly improved (p = 0.031), as well as the bactericidal activity (p = 0.0012) in the Treatment group. No differences were found in the inflammatory status parameters. The final weight (p = 0.006) and the average daily gain at d₃₀ (p < 0.0001) were significantly improved by the treatment. No differences were found in terms of carcass characteristics, while the fecal content of NDF (p < 0.0001), ADF (p = 0.0003), and starch (p < 0.0001) were significantly reduced by the treatment. The result of the present study suggests that the nutraceutical mixture used can support the animal’s immune systems, improving its ability to react against pathogens, as well as feed efficiency and growth performances during the whole fattening period.

中文翻译：

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在新来肉牛适应阶段补充活酵母、甘露聚糖和有机硒：对健康状况、免疫功能和生长性能的影响

评估了基于活酵母 (LY)、甘露寡糖 (MOS) 和有机硒 (Se) 的营养食品混合物对新接收肉牛育肥过程中的健康状况以及免疫功能和生长性能的影响。总共 1036 头夏洛来小母牛被分配到两个实验组：（i）对照组，没有任何营养支持（n = 487；初始体重 = 325 ± 21 kg）；(ii) 治疗组，在前 30 天内补充 LY（5 克/头/天）、有机硒（3 毫克/头/天）和 MOS（10 克/头/天）（n = 549 ；初始重量 = 323 ± 23 kg）。监测了牛呼吸系统疾病 (BRD) 和其他健康问题的发生率以及死亡率。在第₀天采集血样d ₃₀评估免疫功能和炎症状态。记录生长性能、粪便化学成分和胴体特征。治疗组的 BRD 发生率趋于减少 ( p = 0.06)。接种后 BHV-1 抗体的产生显着改善 ( p = 0.031)，以及治疗组的杀菌活性 ( p = 0.0012)。炎症状态参数没有发现差异。最终体重 ( p = 0.006) 和第₃₀天的平均日增重( p < 0.0001) 通过治疗得到显着改善。在胴体特征方面没有发现差异，而粪便中 NDF ( p < 0.0001)、ADF ( p = 0.0003) 和淀粉 ( p < 0.0001) 的含量通过处理显着降低。本研究的结果表明，所使用的营养保健品混合物可以支持动物的免疫系统，提高其对抗病原体的能力，以及整个育肥期间的饲料效率和生长性能。