不同木聚糖水平饲粮中添加木聚糖酶对断奶仔猪生长性能及肠道微生态环境的影响

Xylanase Supplementation of Diets Containing Different Levels of Xylan for Weaned Piglets: Effects on Growth Performance and Intestinal Microecology

本试验旨在研究不同木聚糖水平饲粮中添加木聚糖酶对断奶仔猪生长性能、肠道微生物代谢产物和菌群数量的影响。选择30头体重相近,遗传背景相似的28日龄＂杜×长×大＂三元杂交断奶阉公猪,采用2×3因子试验设计,设2个饲粮木聚糖酶添加量（0和1 000U/kg）和3个饲粮木聚糖水平（4.58%、6.23%和7.54%）,将仔猪随机分为6个处理,每个处理5个重复,每个重复1头猪,试验期14d。结果表明：试验1~14d,添加木聚糖酶能显著提高仔猪平均日增重（P〈0.05）;添加木聚糖酶趋于提高回肠内容物乙酸含量（P〉0.05）,显著提高总挥发性脂肪酸含量（P〈0.05）,显著降低盲肠内容物氨含量（P〈0.05）,显著增加盲肠内容物双歧杆菌数量（P〈0.05）,且以上各项指标均以饲粮木聚糖水平为7.54%时,木聚糖酶的添加效果最为明显。但饲粮木聚糖水平对于以上指标均无显著影响（P〉0.05）。综上所述,在本试验条件下,添加木聚糖酶可以提高断奶仔猪生长性能,并在一定程度上改善肠道微生态环境,且木聚糖酶的作用效果与饲粮木聚糖水平存在着剂量依赖关系。

A 2×3 factorial design was conducted to study the effects of dietary xylan level and xylanase supplementation on growth performance,intestinal microbial metabolites and intestinal flora of weaned piglets.Tow main factors were xylanase supplementation（0 and 1 000 U/kg） and dietary xylan level（4.58%,6.23% and 7.54%）.Thirty cross-bred（Duroc×Landrace×Large white） weaned piglets at 28 days of age with the similar weight and genetic background were randomly allotted to 6 treatments with 5 replicates each and 1 piglet in each replicate.The experiment lasted for 14 days.The results showed that during the experimental period from 1 to 14 days,the supplementation of xylanase increased the average daily gain（P0.05）.The supplementation of xylanase tended to improve the acetate content of ileum digesta（P0.05）,and improved the total volatile fatty acid content of ileum digesta（P0.05）,reduced the ammonia content of caecum digeta（P0.05）,and increased the amount of Bifidobacterium in caecum digeta（P0.05）.When dietary xylan level was 7.54%,the most significant effect of xylanase supplementation was found in those indexes（P0.05）.However,dietary xylan level did not significantly affect those indexes.In conclusion,under the condition of this trial,the supplementation of xylanase can improve growth performance and intestinal microenvironment of weaned piglets.In addition,there is a dose-dependent relationship between xylanase supplementation and dietary xylan level.