仔猪饲粮木聚糖水平与添加木聚糖酶对养分消化率的影响

Effect of Dietary Xylan Level and Xylanase Supplementation on Nutrient Digestibilties in Piglet Diets

本研究包括2个消化试验,分别研究仔猪对饲粮木聚糖的耐受能力和添加木聚糖酶的效果。试验1:设计5个饲粮木聚糖水平。试验2:以含7.25%木聚糖饲粮为基础,分别添加0、720、1 440、1 880、5 760 U/kg木聚糖酶。结果表明:随着饲粮木聚糖含量的增加,能量、粗蛋白、酸性洗涤纤维、有机物、钙和磷的消化率下降;当木聚糖含量为8.44%时,养分消化率的降低达到了显著或极显著水平。回归分析表明,养分消化率与饲粮木聚糖含量之间呈较强的负相关,木聚糖酶的添加可以提高饲粮的养分消化率。由此得出:约15 kg体重的仔猪对饲粮木聚糖具有较强的耐受力,随着木聚糖含量的增加,饲粮养分的消化率呈不同幅度的下降;当木聚糖含量达到或高于7.25%时,添加木聚糖酶对养分消化率有一定的改进效果。

Two digestive experiments were conducted to study the piglet tolerance to dietary xylan and the effect of xylanase supplementation on nutrient digestibihies in diet. Exp.1 contained five diets, the xylan contents of which were 4.19%, 5.33%, 6.47%, 7.25% and 8.44%, respectively. Exp.2 used the diets containing 7.25% xylan without enzyme and with four levels of xylanase（0, 720, 1 440, 1 880,5 760 U/kg）o The results showed nutrient digestibilities decreased with the increase of the xylan contents in piglet diets. Regression analysis showed that there were linear relationships between nutrient digestibilities and dietary xylan contents, and that all regressive coefficients were negative. Xylanase supplementation increased nutrient digestibilities of the diet containing 7.25% xylan： It is concluded that about 15 kg piglets could tolerate some content of dietary xylan, and as dietay xylan content increased, nutrient digestibilities were decreased to a different degree. Xylanase supplementation did not improve significantly nutrient digestibilities until dietary xylan content reached or exceeded 7.25%.