There is increasing research interest in using short-chain fatty acids (SCFAs) including butyrate as potential alternatives to antibiotic growth promoters in animal production. This study was conducted to evaluate the effects of supplementation of sodium butyrate (SB) in liquid feeds (milk, milk replacer, and the mixture of both) on the growth performance, rumen fermentation, and serum antioxidant capacity and immunoglobins in dairy calves before weaning. Forty healthy female Holstein calves (4-day-old, 40 ± 5 kg of body weight) were housed in individual hutches and randomly allocated to 1 of 4 treatment groups (n = 10 per group) using the RAND function in Excel. The control group was fed no SB (SB0), while the other three groups were supplemented with 15 (SB15), 30 (SB30), or 45 (SB45) g/d of SB mixed into liquid feeds offered. The calves were initially fed milk only (days 2 to 20), then a mixture of milk and milk replacer (days 21 to 23), and finally milk replacer only (days 24 to 60). The SB supplementation enhanced growth and improved feed conversion into body weight gain compared with the SB0 group, and the average daily gain increased quadratically with increasing SB supplementation. No significant effect on rumen pH; concentrations of NH3-N, individual and total VFAs; or acetate: propionate (A:P) ratio was found during the whole experimental period. Serum glutathione peroxidase activity increased linearly with the increased SB supplementation, while the serum concentration of maleic dialdehyde linearly decreased. Serum concentrations of immunoglobulin A, immunoglobulin G, or immunoglobulin M were not affected by the SB supplementation during the whole experimental period. Under the conditions of this study, SB supplementation improved growth performance and antioxidant function in pre-weaned dairy calves. We recommended 45 g/d as the optimal level of SB supplementation mixed into liquid feeds (milk or milk replacer) to improve the growth and antioxidant function of dairy calves before weaning.

中文翻译：

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断奶前补充丁酸钠可改善乳牛犊的生长和抗氧化功能

使用短链脂肪酸（SCFA）包括丁酸酯作为动物生产中抗生素生长促进剂的潜在替代品的研究兴趣日益增加。进行这项研究的目的是评估断奶前在液态饲料（牛奶，代乳粉和两者的混合物）中添加丁酸钠（SB）对乳牛犊的生长性能，瘤胃发酵以及血清抗氧化能力和免疫球蛋白的影响。 。将40只健康的雌性荷斯坦犊牛（4天大，体重40±5公斤）放在各个小笼中，并使用Excel中的RAND函数将其随机分配给4个治疗组中的1个（每组n = 10）。对照组不饲喂SB（SB0），而其他三组则分别向饲料中添加15（SB15），30（SB30）或45（SB45）g / d的SB。小牛最初只喂牛奶（第2至20天），然后喂牛奶和代乳粉的混合物（第21至23天），最后只喂代乳粉（第24至60天）。与SB0组相比，补充SB可以促进生长，并改善饲料转化为体重的增加，并且随着SB补充量的增加，平均日增重增加了两倍。对瘤胃pH无明显影响；NH3-N浓度，单个和全部VFA；或在整个实验期间发现乙酸盐：丙酸盐（A：P）的比率。血清谷胱甘肽过氧化物酶活性随SB添加量的增加而线性增加，而马来二醛的血清浓度则线性下降。血清中免疫球蛋白A，免疫球蛋白G，在整个实验期间，SB或免疫球蛋白M不受补充SB的影响。在这项研究的条件下，添加SB可以改善断奶前犊牛的生长性能和抗氧化功能。我们建议将45 g / d作为添加到液体饲料（牛奶或牛奶替代品）中的SB的最佳添加水平，以改善断奶前奶牛的生长和抗氧化功能。