Liu Shuai, Wu Junda, Wu Zhaohai, Alugongo Gibson Maswayi, Zahoor Khan Muhammad, Li Jinghui, Xiao Jianxin, He Zhiyuan, Ma Yulin, Li Shengli, Cao Zhijun
State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
Institute of Animal Husbandry and Veterinary, Guizhou Academy of Agricultural Sciences, Guizhou 550005, China.
Anim Nutr. 2022 Jun 21;10:399-411. doi: 10.1016/j.aninu.2022.06.004. eCollection 2022 Sep.
Butyrate and its derivatives possess various nutritional and biological benefits for mammals, whereas its effects on dairy calves have not been well characterized. This study evaluated the effects of tributyrin administration on blood immune, intestinal immune and barrier functions, and microbial composition of pre-weaned dairy calves. Twenty newborn Holstein bull calves were randomly assigned into a control group (no tributyrin supplementation, CON; = 10) or a treatment group (supplemented with tributyrin at 2 g/L of milk, TRB; = 10). The results showed that diarrhea frequency was decreased significantly by tributyrin administration from d 29 to 56 ( < 0.001) and the whole period ( = 0.003, d 1 to 56) though no significant effects were observed on growth performance. For blood metabolites, tributyrin administration significantly reduced the concentration of interleukin-1β () on d 28 ( = 0.001) and tended to reduce the concentration of serum amyloid A on d 56 ( = 0.079), whereas serum oxidative status parameters were not affected. For intestinal development, tributyrin administration increased the villus height ( < 0.001) and the ratio of villus height to crypt depth ( = 0.046) in the jejunum, and the villus height in the ileum ( = 0.074). Furthermore, toll-like receptor 2 (, = 0.045) and ( = 0.088) gene expressions were downregulated, while claudin-4 ( = 0.022) gene expression was upregulated in the jejunum following tributyrin administration. In the ileum, claudin-4 ( = 0.029) and G-protein coupled receptor 41 ( = 0.019) gene expressions were upregulated in the TRB group compared to CON. No significantly higher abundances of microbiota were found in the jejunum or ileum of calves in the CON group. In the TRB group, supplementing tributyrin significantly increased the abundance of short-chain fatty acid (SCFA)-producing bacteria, including Ruminococcaceae, Lachnospiraceae, and Rikenellaceae (LDA >3.5, < 0.05), which was negatively associated with inflammatory gene expression ( and ) but positively associated with intestinal barrier genes (claudin-4) and morphological parameters ( < 0.05). In conclusion, supplementing tributyrin in milk replacer could improve intestinal development and health of pre-weaned dairy calves by stimulating SCFA-producing bacteria colonization, enhancing intestinal barrier functions and suppressing inflammatory responses.
丁酸及其衍生物对哺乳动物具有多种营养和生物学益处，但其对犊牛的影响尚未得到充分研究。本研究评估了甘油三丁酸酯给药对断奶前犊牛血液免疫、肠道免疫和屏障功能以及微生物组成的影响。将20头新生荷斯坦公牛犊随机分为对照组（不补充甘油三丁酸酯，CON；n = 10）或治疗组（在牛奶中添加2 g/L甘油三丁酸酯，TRB；n = 10）。结果表明，从第29天到第56天，甘油三丁酸酯给药显著降低了腹泻频率（P < 0.001），在整个时期（第1天到第56天，P = 0.003）也有显著降低，尽管对生长性能没有显著影响。对于血液代谢物，甘油三丁酸酯给药在第28天显著降低了白细胞介素-1β（IL-1β）的浓度（P = 0.001），并在第56天倾向于降低血清淀粉样蛋白A的浓度（P = 0.079），而血清氧化状态参数未受影响。对于肠道发育，甘油三丁酸酯给药增加了空肠中的绒毛高度（P < 0.001）和绒毛高度与隐窝深度的比值（P = 0.046），以及回肠中的绒毛高度（P = 0.074）。此外，在甘油三丁酸酯给药后，空肠中的Toll样受体2（TLR2，P = 0.045）和TLR4（P = 0.088）基因表达下调，而紧密连接蛋白4（claudin-4，P = 0.022）基因表达上调。在回肠中，与CON组相比，TRB组中紧密连接蛋白4（P = 0.029）和G蛋白偶联受体41（P = 0.019）基因表达上调。在CON组犊牛的空肠或回肠中未发现微生物群丰度显著更高。在TRB组中，补充甘油三丁酸酯显著增加了产生短链脂肪酸（SCFA）的细菌的丰度，包括瘤胃球菌科、毛螺菌科、梭菌属和理研菌科（线性判别分析得分>3.5，P < 0.05），这与炎症基因表达（IL-1β和TLR4）呈负相关，但与肠道屏障基因（claudin-4）和形态学参数呈正相关（P < 0.05）。总之，在代乳粉中补充甘油三丁酸酯可以通过刺激产生SCFA的细菌定植、增强肠道屏障功能和抑制炎症反应来改善断奶前犊牛的肠道发育和健康。
