This experiment was conducted to evaluate the effects of different levels of tannic acid (TA) on growth performance, diarrhea rate, nutrient digestibility and intestinal health in weaned piglets. A total of 180 weaned piglets (Duroc × Landrace × Yorkshire, 24 d of age, initial average BW = 7.77 ± 0.17 kg) were allotted to 5 groups (6 pigs/pen and 6 replicates/group) in a randomized complete block design according to their gender and body weight. Piglets were fed a basal diet, or the basal diet supplemented with 0.05%, 0.1%, 0.2% or 0.4% TA for 28 d. The supplementary levels of TA in the diets were obtained by adding tannalbin containing 51% TA and 40.17% protein. The results showed that, compared with the CON group, dietary TA did not affect ADFI, ADG or F:G, and linearly reduced (P < 0.01) the diarrhea rate and diarrhea index of piglets. There were no significant effects on apparent total tract digestibility (ATTD) in the 0.05%, 0.1% and 0.2% TA groups, while negative effects (P < 0.05) on apparent digestibility of crude protein and gross energy were observed in the 0.4% TA group. In addition, the nutrient digestibility of dry matter, crude protein and gross energy linearly decreased (P < 0.01) with the increase of TA dosage. Supplementation of TA increased (P < 0.05) the villus height of the duodenum and jejunum, as well as increased (P < 0.05) catalase (CAT) activity in serum. Dietary TA improved (P < 0.05) the Bacillus counts in cecal digesta. Further, TA significantly improved (P < 0.05) Bacillus counts and reduced (P < 0.05) the Escherichia coli counts in colonic digesta. The concentration of acetic acid, propionic acid, butyric acid and isovaleric acid in cecal digesta were significantly increased (P < 0.05). The mRNA expression level of zonula occludens-1 (ZO-1), zonula occludens-2 (ZO-2), and claudin-2 (CLDN-2) in the jejunum were greater (P < 0.05) in TA supplemented groups. The study showed that, compared to the control, TA prevented post-weaning diarrhea and improved intestinal health of weaned piglets, and the appropriate level of TA supplementation would be from 0.1% to 0.2%.

本实验旨在评估不同水平单宁酸 (TA) 对断奶仔猪生长性能、腹泻率、营养物质消化率和肠道健康的影响。总共 180 头断奶仔猪（杜洛克 × 长白 × 约克夏，24 日龄，初始平均体重 = 7.77 ± 0.17 kg）被分配到 5 组（6 头猪/栏和 6 个重复/组），根据随机完整区组设计他们的性别和体重。仔猪饲喂基础日粮或添加 0.05%、0.1%、0.2% 或 0.4% TA 的基础日粮，持续 28 天。日粮中 TA 的补充水平是通过添加含有 51% TA 和 40.17% 蛋白质的单宁糖获得的。结果显示，与CON组相比，膳食TA对ADFI、ADG或F:G均无影响，且呈线性降低（P < 0.01）仔猪的腹泻率和腹泻指数。0.05%、0.1%和0.2% TA组对表观全消化道消化率（ATTD）无显着影响，而0.4% TA组 对粗蛋白表观消化率和总能量有负面影响（P < 0.05）团体。此外，干物质、粗蛋白和总能的养分消化率 随着TA用量的增加而线性下降（P < 0.01）。TA 的补充增加（P  < 0.05）十二指肠和空肠的绒毛高度，以及增加（P  < 0.05）血清中的过氧化氢酶（CAT）活性。膳食TA改善（P  <0.05）芽孢杆菌在盲肠消化液中计数。此外，TA 显着提高 ( P  < 0.05)芽孢杆菌计数并减少 ( P  < 0.05)结肠消化物中的大肠杆菌计数。盲肠食糜中乙酸、丙酸、丁酸和异戊酸的浓度显着升高（P  < 0.05）。空肠中封闭小带-1（ZO-1）、封闭小带-2（ZO-2）和封闭蛋白-2（CLDN-2）的mRNA表达水平较高（P < 0.05) 在 TA 补充组中。研究表明，与对照组相比，TA 可预防断奶后腹泻并改善断奶仔猪的肠道健康，TA 的适当补充水平为 0.1% 至 0.2%。