State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, P. R. China.
Poult Sci. 2014 Jan;93(1):94-103. doi: 10.3382/ps.2013-03188.
Necrotic enteritis caused by Clostridium perfringens has become prevalent in the European Union due to the withdrawal of antibiotics in poultry feed. In an experiment with a 2 × 2 factorial arrangement, 336 one-day-old male broiler chicks (Ross 308) were assigned to 4 groups with or without C. perfringens challenge and fed wheat-based diets supplemented with or without xylanase at 5,500 U/kg of diet. The study aimed to investigate effects of xylanase addition on growth performance as well as nutrient digestion and absorption of C. perfringens-infected broilers. Before challenge (d 0-14), xylanase-supplemented birds had greater ADG and lower feed conversion ratio (FCR; P < 0.05). During infection (d 14-21), challenge tended to decrease ADG (P = 0.063) and significantly increased FCR (P < 0.05), whereas xylanase addition greatly reduced FCR (P < 0.05). Clostridium perfringens infection decreased AME values and apparent ileal digestibility of DM of diets (P < 0.05). Xylanase supplementation increased AME values regardless of infection and apparent ileal digestibility of CP in challenged birds (P < 0.05). Activities of duodenal α-amylase and chymotrypsin and pancreatic trypsin were decreased by C. perfringens infection (P < 0.05). Xylanase supplementation elevated pancreatic chymotrypsin activity and reduced duodenal α-amylase and trypsin activities (P < 0.05). It also decreased jejunal α-amylase activity and increased pancreatic α-amylase as well as jejunal sucrase activities in uninfected birds (P < 0.05). The duodenal mRNA expression of sodium glucose cotransporter 1 (SGLT1), H(+)-dependent peptide transporter 1 (PepT1), and liver fatty acid-binding protein (L-FABP) were downregulated (P < 0.05), but ileal SGLT1 gene expression was increased by infection (P < 0.05). Xylanase addition upregulated expression of jejunal SGLT1, PepT1, and L-FABP genes as well as ileal PepT1 and L-FABP genes in challenged broilers (P < 0.05). In conclusion, xylanase supplementation of wheat-based diets improved FCR and AME in birds irrespective of C. perfringens infection and elevated apparent ileal digestibility of CP and mRNA expression of nutrient transporters in challenged birds.
由于在禽饲料中撤抗生素，产气荚膜梭菌引起的坏死性肠炎在欧盟变得普遍。在一项具有 2×2 析因设计的试验中，336 只 1 日龄雄性肉鸡（罗斯 308）被分配到 4 组，分别为产气荚膜梭菌攻毒组和非攻毒组，以及添加或不添加 5500 U/kg 日粮木聚糖酶的小麦型日粮组。本研究旨在研究添加木聚糖酶对感染产气荚膜梭菌肉鸡生长性能以及养分消化和吸收的影响。攻毒前（第 0-14 天），添加木聚糖酶的鸡只具有更大的平均日增重和更低的饲料转化率（P＜0.05）。在感染期间（第 14-21 天），攻毒有降低平均日增重的趋势（P=0.063）和显著增加饲料转化率的作用（P＜0.05），而添加木聚糖酶则大大降低了饲料转化率（P＜0.05）。产气荚膜梭菌感染降低了代谢能值和日粮中 DM 的表观回肠消化率（P＜0.05）。添加木聚糖酶增加了感染和未感染鸡的代谢能值和 CP 的表观回肠消化率（P＜0.05）。产气荚膜梭菌感染降低了十二指肠α-淀粉酶和糜蛋白酶以及胰腺胰蛋白酶的活性（P＜0.05）。添加木聚糖酶提高了胰腺糜蛋白酶的活性，降低了十二指肠α-淀粉酶和胰蛋白酶的活性（P＜0.05）。它还降低了空肠α-淀粉酶的活性，增加了胰腺α-淀粉酶和空肠蔗糖酶的活性（P＜0.05）。未感染鸡的十二指肠钠葡萄糖协同转运蛋白 1（SGLT1）、H+依赖肽转运蛋白 1（PepT1）和肝脂肪酸结合蛋白（L-FABP）的 mRNA 表达被下调（P＜0.05），但感染增加了回肠 SGLT1 基因的表达（P＜0.05）。添加木聚糖酶增加了感染鸡的空肠 SGLT1、PepT1 和 L-FABP 基因以及回肠 PepT1 和 L-FABP 基因的表达（P＜0.05）。总之，在小麦型日粮中添加木聚糖酶可提高感染和未感染产气荚膜梭菌的鸡的饲料转化率和代谢能值，并提高感染鸡的 CP 表观回肠消化率和养分转运蛋白的 mRNA 表达。
