Wu Wei, Zhou Huajin, Chen Yanhong, Guo Yuming, Yuan Jianmin
State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, PR China.
J Anim Sci Biotechnol. 2023 Mar 9;14(1):34. doi: 10.1186/s40104-023-00834-3.
Corn arabinoxylan (AX) is a complicated and multibranched antinutritional factor, thereby proving the use of endo-xylanase (EX) to be marginally valid. This study focused on specific types of AX-degrading enzymes (ADEs) to exert the synergy of debranching enzymes and track the prebiotic potential of enzymatic hydrolysates. This study investigated the effects of ADEs on the growth performance, intestinal histomorphology, absorption functions, changes in polysaccharide components, fermentation, and gut microbiota of broiler chickens. Five hundred seventy-six five-day-old Arbor Acres male broiler chickens were randomly allocated into eight treatments with six replicates each. Corn basal diets supplemented with or without enzymes were fed for a 21-day period, specifically including EX, its compatible use with arabinofuranosidase (EXA) or ferulic acid esterase (EXF), and compound groups with the above three enzymes (XAF).
Specific ADEs stimulated the jejunal villus height and goblet cell number and evidently decreased the crypt depth (P < 0.05), while the ratio of ileal villus height to crypt depth was significantly increased in EXF (P < 0.05). Maltase activities of ileal mucosa in XAF groups were extremely enhanced (P < 0.01), and EX boosted the activity of Na-K ATPase in the small intestine (P < 0.01). The insoluble AX concentrations comparatively lessened, thereby notably raising the sundry xylooligosaccharide (XOS) yield in the ileal chyme (P < 0.05), which was dominant in xylobiose and xylotriose. Improvements in the abundance and diversity of ileal microbial communities within the EXA, EXF, and XAF treatments were observed (P < 0.05). Positive correlations between microbiota and XOS were revealed, with xylobiose and xylotriose being critical for ten beneficial bacteria (P < 0.05). EXF increased the BWG and FCR of broiler chickens in this phase (P < 0.05), which was attributed to the thriving networks modified by Lactobacillus. The intracecal contents of acetic acid, butyric acid, and propionic acid were greatly enhanced in most ADE groups, such as EXF (P < 0.05).
Debranching enzymes appreciably targeted corn AX to release prebiotic XOS in the posterior ileum and facilitated intracaecal fermentation. It was beneficial for improving gut development, digestion and absorption and modulating the microflora to promote the early performance of broiler chickens.
玉米阿拉伯木聚糖（AX）是一种复杂的多分支抗营养因子，因此使用内切木聚糖酶（EX）的效果有限。本研究聚焦于特定类型的AX降解酶（ADEs），以发挥去分支酶的协同作用，并追踪酶解产物的益生元潜力。本研究调查了ADEs对肉鸡生长性能、肠道组织形态学、吸收功能、多糖成分变化、发酵及肠道微生物群的影响。576只5日龄的艾维茵雄性肉鸡被随机分为8个处理组，每组6个重复。饲喂添加或不添加酶的玉米基础日粮21天，具体包括EX、其与阿拉伯呋喃糖苷酶（EXA）或阿魏酸酯酶（EXF）的联合使用，以及包含上述三种酶的复合组（XAF）。
特定的ADEs可刺激空肠绒毛高度和杯状细胞数量增加，并显著降低隐窝深度（P<0.05），而EXF组回肠绒毛高度与隐窝深度之比显著升高（P<0.05）。XAF组回肠黏膜麦芽糖酶活性显著增强（P<0.01），EX可提高小肠中钠钾ATP酶的活性（P<0.01）。不溶性AX浓度相对降低，从而显著提高回肠食糜中多种低聚木糖（XOS）的产量（P<0.05），其中木二糖和木三糖占主导。观察到EXA、EXF和XAF处理组回肠微生物群落的丰度和多样性有所改善（P<0.05）。揭示了微生物群与XOS之间的正相关关系，木二糖和木三糖对十种有益细菌至关重要（P<0.05）。EXF提高了此阶段肉鸡的平均日增重（BWG）和饲料转化率（FCR）（P<0.05），这归因于由乳酸杆菌修饰的活跃网络。大多数ADE组，如EXF组，盲肠内容物中乙酸、丁酸和丙酸的含量显著增加（P<0.05）。
去分支酶显著作用于玉米AX，在后段回肠释放益生元XOS，并促进盲肠内发酵。这有利于改善肠道发育、消化吸收以及调节微生物群，从而促进肉鸡的早期生长性能。
