这篇论文的目的是确定饲料里添加山麻橘精油（LEO）对断奶的小猪的生长性能、免疫功能、抗氧化水平、肠形态和微生物组成的影响。随机选取192头刚断奶、体重平均为6.85±0.22公斤的杜洛克×大白×长白杂交猪，将其随机分为4组，每组8个重复样本，分别喂以基础饲料（CON）或含100（LLEO）、200（MLEO）和400（HLEO）毫克/千克LEO的饲料。结果显示，与CON相比，HLEO补充剂（P＜0.05）增加了28天时的平均日增重。MLEO和HLEO补充剂减少了（P＜0.05）饲料转化率。含LEO的饲料具有更低的腹泻率（P＜0.05）。HLEO补充剂增加了血清和肝脏的总抗氧化能力（T-AOC）（P＜0.05）。同时，MLEO和HLEO补充剂导致血清和肝脏中过氧化物酶（GPx）活性更高（P＜0.05）。HLEO补充剂增加了血清免疫球蛋白A、免疫球蛋白G和白细胞介素10（P＜0.05），而MLEO和HLEO补充剂则降低了肿瘤坏死因子-α（P＜0.05）。HLEO组的十二指肠或空肠绒毛高度增加了（P＜0.05），MLEO组的空肠绒毛高度/墓深比也有所改善（P＜0.05）。LEO的添加增加了盲肠微生物群落的丰富度和多样性（P＜0.05），主要增加了Oscillospiraceae_UCG-005，Faecalibacterium，Blautia和Coprococcus的相对丰度。被HLEO补充剂的小猪的盲肠乙酸和结肠丙酸等短链脂肪酸（SCFA）的浓度也增加了（P＜0.05）。总之，这些发现表明，LEO补充剂能改善断奶小猪的生长性能和肠道健康。© 2022 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.

This paper was to determine the effects of dietary Litsea cubeba essential oil (LEO) supplementation on growth performance, immune function, antioxidant level, intestinal morphology and microbial composition in weaned piglets. One hundred and ninety-two piglets (Duroc × [Large White × Landrace]) with 6.85 ± 0.22 kg mean body weight weaned at 21 d of age were randomly assigned to 4 treatment groups with 8 replicates and were fed with a basal diet (CON) or CON diet containing 100 (LLEO), 200 (MLEO) and 400 (HLEO) mg/kg LEO. The results revealed that HLEO supplementation (P < 0.05) increased the average daily gain on d 28 compared with CON. MLEO and HLEO supplementation decreased (P < 0.05) feed conversion ratio. LEO-containing diets had a lower (P < 0.05) diarrhea rate. Supplementation with HLEO increased (P < 0.05) total antioxidant capacity (T-AOC) both in the serum and liver. Meanwhile, the supplementation of MLEO and HLEO resulted in higher (P < 0.05) glutathione peroxidase (GPx) activities both in serum and liver. Supplementation of HLEO increased (P < 0.05) serum immunoglobulin A, immunoglobulin G and interleukin-10, whereas supplementation with MLEO and HLEO decreased (P < 0.05) tumor necrosis factor-α. Villus height in the duodenum or jejunum was increased (P < 0.05) in the HLEO group, and the villus height to crypt depth ratio in the jejunum was also improved (P < 0.05) in the MLEO group. The addition of LEO increased (P < 0.05) the richness and diversity of the microbial community in the cecum, which mainly increased the relative abundance of Oscillospiraceae _UCG-005, Faecalibacterium, Blautia and Coprococcus. Piglets supplemented with HLEO increased (P < 0.05) the concentration of short chain fatty acids (SCFA), including acetic acid in the cecum and propionic acid in the colon. In conclusion, these findings indicated that LEO supplementation improved growth performance and intestinal health in weaned piglets.© 2022 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.