高通量测序技术研究不同喂养和分娩方式对不同月龄婴幼儿肠道菌群的影响

采用高通量测序技术分析比较54 份不同喂养方式（母乳、羊乳配方粉、牛乳配方粉）、不同分娩方式（顺产、剖宫产）和不同月龄（I段：0～6?个月、II段：6～12?个月、III段：12～36?个月）婴幼儿粪便样本，研究不同影响因素下婴幼儿肠道菌群的构成，尤其是羊乳配方粉对婴幼儿肠道构成的影响，分析肠道菌群的丰度及多样性，比较优势菌丰度，为婴儿配方食品的开发及婴幼儿科学喂养提供技术支撑。结果表明：在相同喂养方式、相同月龄的婴幼儿中，分娩方式对其肠道菌群影响不尽相同，I段顺产母乳喂养组中门水平Actinobacteria（放线菌门）、Firmicutes（厚壁菌门）、Bacteroidets（拟杆菌门）、Proteobacteria（变形菌门）的相对丰度分别为43.74%、25.48%、17.93%、9.71%；I段剖宫产母乳喂养组分别为40.83%、44.31%、3.81%、11.01%；II段顺产羊乳配方粉喂养组分别为41.44%、43.84%、8.38%、6.27%；II段剖宫产羊乳配方粉喂养组分别为60.76%、24.85%、8.66%、5.70%；III段顺产羊乳配方粉喂养组分别为26.58%、47.73%、24.07%、1.58%；III段剖宫产羊乳配方粉喂养组分别为34.77%、51.94%、11.10%、2.16%。在分娩方式相同且相同月龄的婴幼儿中，喂养羊乳配方粉的婴幼儿肠道菌群构成更为多样，且主要优势菌相对丰度更高，Actinobacteria在I段顺产羊乳配方粉喂养组中占62.98%，在I段顺产母乳喂养组中占43.74%；Bacteroidets在II段顺产羊乳配方粉喂养组中占43.84%，在II段顺产牛乳配方粉喂养组中占35.71%。对于相同分娩方式、相同喂养方式的婴幼儿，随着月龄的增长其肠道菌群构成存在显著差异（P＜0.05），以II段婴幼儿肠道菌群更为多样，且Lactobacillales（乳杆菌目）较I、III段相对丰度更高，为差异显著的优势菌。本研究为婴幼儿的健康、代谢及相关疾病的防御提供参考依据。

Effects of Feeding and Delivery Modes on Intestinal Flora of Infants of different Ages Investigated by High-Throughput Sequencing

High-throughput sequencing technology was used to analyze the difference in the intestinal flora of infants of different age groups (I: 0–6 months old, II: 6–12 months old, III: 12–36 months old) subjected to different feeding methods (breast milk, goat milk, and cow milk) and different delivery modes (vaginal delivery and cesarean section). A total of 54 fecal samples were collected and used to determine the composition of intestinal flora with a special focus on the influence of goat milk infant formula on the intestinal flora. Meanwhile, the abundance and diversity of intestinal flora were analyzed and the abundance of dominant bacteria was compared. By doing so, this study aimed to provide technical support for the development of new infant formulas and scientific feeding of infants. The results showed that different delivery modes had different effects on the intestinal microbiota of infants of the same age with the same feeding pattern. At the phylum level, the relative abundance of Actinobacteria, Firmicutes, Bacteroidets and Proteobacteria were 43.74%, 25.48%, 17.93% and 9.71%, respectively in breasted infants vaginally delivered, and 40.83%, 44.31%, 3.81% and 11.01%, respectively in those born by caesarean section in the 0 to 6 month age group; 41.44%, 43.84%, 8.38% and 6.27%, respectively in goat milk infant formula-fed infants vaginally delivered, and 60.76%, 24.85%, 8.66% and 5.70%, respectively in those born by cesarean section in the 6 to 12 month age group; 26.58%, 47.73%, 24.07% and 1.58%, respectively in infant formula-fed infants vaginally delivered, and 34.77%, 51.94%, 11.10% and 2.16% in those born by cesarean section in the 12 to 36 month age group. For the same delivery mode and the same age, the composition of intestinal flora in infants fed on goat milk infant formula was more diverse and the abundance of dominant bacteria was higher, Actinobacteria accounting for 62.98% and 43.74% of the total abundance in vaginally delivered infants fed on goat milk infant formula and breastmilk in the 0 to 6 month age group, respectively, and Bacteroidets accounting for 43.84% and 35.71% for those in the 6 to 12 month age group, respectively. For infants delivered by the same route and fed by the same method, the composition of intestinal flora changed significantly with age (P < 0.05). The intestinal flora in the 6 to 12 month age group was more diverse than in the other age groups and Lactobacillales had the highest relative abundance in this age group and was the dominant bacteria, with significant differences being observed compared with other bacteria detected. This study provides a rationale to protect infant health and defend against metabolic diseases.