日粮添加褐藻糖胶对断奶仔猪抗炎能力和肠道微生物多样性的影响

Influence of dietary fucoidan on inflammatory response and intestinal microbial diversity in weaned pigs

摘要:

[目的]本试验旨在研究日粮添加海带提取物褐藻糖胶对断奶仔猪生长性能、营养物质消化率、机体免疫力和肠道微生物多样性的影响。[方法]试验选用36头初始体重为（7.43±0.12）kg的健康仔猪，按照随机区组设计分为3组，每组12头。日粮处理组分别为不含抗生素的基础日粮组、抗生素组和褐藻糖胶组；试验期为28 d。评价褐藻糖胶对仔猪生长性能和营养物质消化率的影响；通过比色法和酶联免疫吸附法检测血清中与免疫相关的指标；通过16S rRNA扩增子高通量测序检测试验第0、14和28天肠道微生物多样性。[结果]日粮添加褐藻糖胶可降低试验0-14 d仔猪耗料增重比（P<0.05），但对试验全期仔猪平均日增重和平均日采量无显著影响（P>0.05）。与对照组相比，饲喂褐藻糖胶日粮后，仔猪的中性洗涤纤维和酸性洗涤纤维表观消化率显著提高（P<0.05）；仔猪饲喂抗生素和褐藻糖胶日粮后，血清IL-22含量显著降低。试验第14天，抗生素组和褐藻糖胶处理组中Bacteroidetes数量呈上升趋势（P=0.07）；试验第28天，抗生素组和褐藻糖胶处理组Actinobacteria丰度显著高于对照组（P<0.05），且褐藻糖胶处理组Bacteroides属的菌群丰度显著高于对照组和抗生素组。[结论]日粮添加褐藻糖胶提高了断奶仔猪纤维养分消化率和拟杆菌属的丰富度和多样性，并且降低了促炎性细胞因子IL-22含量，这有助于缓解仔猪的断奶应激反应，建立稳定健康肠道菌群。

Abstract:

[Objective] We studied the effects of dietary fucoidan on growth performance, nutrient digestibility, immune index in serum, and gut microbiota composition in weaned pigs. [Methods] A total of 36 weaned pigs (body weight 7.43±0.12 kg) were allocated to 3 dietary treatments, and piglets in each group received control diet, control diet containing antibiotic, control diet containing fucoidan for 28 days. Growth performance and nutrient digestibility were evaluated in piglets. Serum indices related to immunity were measured by spectrophotometric and ELISA assays. Gut microbiota composition was determined using 16S rRNA amplicon sequencing. [Results] A reduction in feed conversion ratio in piglets fed fucoidan supplementation on 0-14 days (P<0.05). The digestibility of neutral detergent fiber and acid detergent fiber were increased in fucoidan dietary treatment (P< 0.05). Compared with the control group, the production of interleukin 22 decreased in piglets treated with antibiotic and fucoidan intervention (P<0.05). Piglets provided with antibiotic and fucoidan treatments showed an increased tendency (P=0.07) in the population of Bacteroidetes members on day 14, whereas the abundance of Actinobacteria increased (P<0.05) on day 28. Specifically, there was an increase in the Bacteroides genus in diet containing fucoidan when compared to those in control and antibiotic groups. [Conclusion] Dietary fucoidan improved the fiber digestibility and the richness and diversity of Bacteroides genus, and decreased inflammatory cytokines of IL-22 production in weaned pigs. These changes should alleviate the post-weaning stress and contribute to the establishment of healthy and stable digestive system in weaned pigs.