植酸酶对肉鸡生长性能及饲粮养分利用率的影响

饲养试验选用1日龄的良凤花鸡600羽,随机分为4组(每组设3个重复,每个重复50羽),A组为对照组,饲喂玉米-豆粕型基础饲粮,B、C、D组的饲粮为分别以300、500、700 U/kg的植酸酶取代基础饲粮中的30%、50%、70%的磷酸氢钙。结果表明:0～4周龄,与对照组相比,C和D组平均日增重(ADG)分别极显著提高6.29%(P<0.01)和8.27%(P<0.01);平均料重比(F/G),组间差异不显著(P>0.05)。5～8周龄,与对照组相比,B、C和D组的ADG分别有所提高,F/G有所下降,但组间差异不显著(P>0.05)。B、C、D组鸡血清钙、磷、白蛋白、总蛋白、球蛋白含量随着植酸酶添加量的增加呈上升趋势,但差异不显著(P>0.05);血清碱性磷酸酶活性随着植酸酶的添加而呈降低趋势,但差异不显著(P>0.05)。消化代谢试验结果表明,添加不同水平的植酸酶替代饲粮不同比例的磷酸氢钙,肉鸡饲粮干物质、粗蛋白、粗脂肪、粗纤维、粗灰分、钙和能量的表观代谢率虽然比对照组有所改善,但差异不显著(P>0.05);而磷的表观吸收率分别比对照组显著提高了25.39%～32.48%(P<0.01)。

Effects of dietary phytase on growth performance and nutrient utilization in broilers

A total of 600 Liangfeng chickens of one-day-old were randomly divided into 4 groups of 3 replicates and 50 repeated and fed corn-soybean meal diets for 8 weeks.In group A,broilers were fed basal diets with inorganic phosphorus(from dicalcium phosphate,DCP) as control.While in group B,C or D,broilers were fed diets with 40%,60% or 80% of DCP replaced with 300,500 or 700 U phytase/kg,respectively.The results showed that average daily gains(ADG) of group C and D were significantly increased 6.29%(P<0.01) and 8.27%(P<0.01) compared with the control group during 0-4 weeks;but no significant difference in average feed conversion(F/G) among the groups(P>0.05).During 5-8 weeks,ADG of group B,C and D were increased,F/G decreased to some extent,but the difference between the groups was not significant(P>0.05) compared with the control.Serum calcium,phosphorus,albumin,total protein and globulin levels tended to increase in group B,C,D,with the amount of phytase increasing in diets,but the difference was not significant among the groups(P>0.05);the activity of serum alkaline phosphatase was decreased with the using of phytase,but the difference was not significant among the groups(P>0.05).Results of metabolism trial showed that adding different levels of phytase to replace different proportions of dietary DCP tended to improve apparent metabolizability of dietary nutrient such as dry matter,crude protein,ether extract,crude fiber,Ca and energy,but the difference was not significant among the groups(P>0.05);while the apparent absorption rate of phosphorus were significantly increased 25.39%~32.48%(P<0.01) comparing with control.