Institute of Feed Research of Chinese Academy of Agricultural Sciences, Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural Affairs, Beijing 100081, China.
College of Animal Science, Shanxi Agricultural University, Taigu 030801, China.
J Anim Sci. 2023 Jan 3;101. doi: 10.1093/jas/skac414.
The present study evaluated the effects of dietary medium-chain fatty acid (MCFA) and Bacillus on growth performance, nutrient digestibility, antioxidant capacity, colonic fermentation, and microbiota of weaning piglets. A total of 400 weaned piglets were randomly divided into 4 treatments, with 10 replicates per treatment and 10 pigs per replicate. The treatment included: basal diet (control, CON), basal diet with 0.588 g/kg MCFA (MCF), basal diet with 1.3 × 109 CFU/kg Bacillus (BAC), and basal diet with 0.588 g/kg MCFA and 1.3 × 109 CFU/kg Bacillus (SYN). Compared with CON group, the average daily gain of MCF and SYN in the early (1 to 9 d) and whole stage (1 to 36 d) of trail were improved (P < 0.05), the feed to gain ratio of MCF in later (10 to 36 d) and whole stage of trial were decreased (P < 0.05), and the diarrhea rate of SYN in the early stage (1 to 9 d) of trial decreased (P < 0.05). The digestibility of dry matter, ether extract, acid detergent fiber digestibility of MCF were decreased (P < 0.05) compared with CON. The serum d-lactic acid in MCF, BAC, and SYN were lower (P < 0.05) compared with CON group. Compared with CON group, the contents of total antioxidant capacity, superoxide dismutase, and glutathione peroxidase were greater (P < 0.05), whereas the content of malondialdehyde and the contents of colonic isobutyrate and isovalerate were lower (P < 0.05) in MCF. The microbial Shannon and Simpson diversity was lower in MCF (P < 0.05) than that in BAC and SYN. The relative abundance of Prevotella was greater (P < 0.05), whereas the Treponema and Oscillibacter were lower (P < 0.05) in MCF than that in BAC and SYN. In addition, the metabolic pathways of bacteria such as pentose phosphate pathway, adenosine nucleotides degradation II were enhanced (P < 0.05), whereas the pathways such as incomplete reductive TCA cycle, and TCA cycle IV (2-oxoglutarate decarboxylase) were decreased (P < 0.05) in MCF compared with BAC. The results indicated that dietary MCFA and Bacillus in combination improved the intestinal barrier function of piglets by changing the intestinal microbiota and its metabolic function, and finally alleviated the diarrhea rate in early weaning stage and improved growth performance in whole trial period. In addition, MCFA was effective in improving feed efficiency and antioxidant capacity of piglets.
本研究评估了膳食中链脂肪酸（MCFA）和芽孢杆菌对断奶仔猪生长性能、养分消化率、抗氧化能力、结肠发酵和微生物区系的影响。将 400 头断奶仔猪随机分为 4 个处理组，每个处理组 10 个重复，每个重复 10 头猪。处理包括：基础日粮（对照，CON）、基础日粮添加 0.588 g/kg MCFA（MCF）、基础日粮添加 1.3×109 CFU/kg 芽孢杆菌（BAC）和基础日粮添加 0.588 g/kg MCFA 和 1.3×109 CFU/kg 芽孢杆菌（SYN）。与 CON 组相比，MCF 和 SYN 在试验早期（1 至 9 d）和整个阶段（1 至 36 d）的平均日增重提高（P<0.05），MCF 在试验后期（10 至 36 d）和整个阶段的饲料增重比降低（P<0.05），SYN 在试验早期（1 至 9 d）的腹泻率降低（P<0.05）。与 CON 相比，MCF 的干物质、乙醚提取物、酸洗涤剂纤维消化率降低（P<0.05）。与 CON 组相比，MCF、BAC 和 SYN 的血清 d-乳酸水平降低（P<0.05）。与 CON 组相比，总抗氧化能力、超氧化物歧化酶和谷胱甘肽过氧化物酶的含量增加（P<0.05），而丙二醛的含量以及结肠异丁酸和异戊酸的含量降低（P<0.05）。与 BAC 和 SYN 相比，MCF 的微生物 Shannon 和 Simpson 多样性较低（P<0.05）。与 BAC 和 SYN 相比，Prevotella 的相对丰度较高（P<0.05），而 Treponema 和 Oscillibacter 的相对丰度较低（P<0.05）。此外，与 BAC 相比，MCF 中的细菌代谢途径如戊糖磷酸途径、腺苷核苷酸降解 II 增强（P<0.05），而不完全还原 TCA 循环和 TCA 循环 IV（2-氧戊二酸脱羧酶）途径减少（P<0.05）。结果表明，日粮 MCFA 和芽孢杆菌通过改变肠道微生物区系及其代谢功能，共同改善了仔猪的肠道屏障功能，最终降低了早期断奶阶段的腹泻率，提高了整个试验期的生长性能。此外，MCFA 能有效提高仔猪的饲料效率和抗氧化能力。
