低水平钙磷日粮添加植酸酶对肉鸡生长性能和养分消化的影响

Effects of phytase supplementation on growth performance and nutrient digestion of broilers fed with low levels of calcium and phosphorus diets

文章旨在探讨植酸酶对饲喂低水平钙磷日粮肉鸡生长性能和养分表观消化率的影响。试验将平均初始体重为(61.56±0.66)g的1日龄肉鸡随机分为4组,每组4个重复,每个重复38只。对照组饲喂正常钙磷水平的玉米豆粕型日粮,T1~T3组饲喂低钙磷水平的玉米豆粕型日粮+0、1000和1500 FIU/kg植酸酶,试验分为1~21 d和22~42 d两个阶段。结果:对照组和T3组42 d肉鸡的体重显著高于T1组(P<0.05),同时T3组22~42 d以及1~42 d肉鸡的平均日增重较T1组分别显著提高8.01%和5.05%(P<0.05)。T3组22~42 d肉鸡饲料报酬较其他组分别显著提高3.3%、3.09%和3.73%(P<0.05)。对照组和T3组钙表观消化率显著高于T1和T2组(P<0.05),T3组干物质、氮和钙沉积率显著高于对照组和T1组(P<0.05),同时T3组磷沉积量最高(P<0.05)。T1组蛋氨酸和苏氨酸表观消化率显著低于T3组(P<0.05),同时T1组亮氨酸、异亮氨酸、甘氨酸和丙氨酸回肠表观消化率均表现最低(P<0.05)。结论:玉米豆粕型低钙磷日粮中添加植酸酶能有效提高钙、磷的营养价值及干物质、氮和氨基酸的代谢率。在较高剂量(1500 FTU/kg)时,对生长后期肉鸡的饲料报酬和氨基酸消化的效益最大。

This experiment was conducted to investigate the effects of phytase on growth performance and nutrient apparent digestion of broilers fed low levels of calcium and phosphorus.One-day-old broilers with an average initial body weight of(61.56±0.66)g were randomly divided into 4 groups with 4 replicates per group and 38 broilers per replicate.The control group was fed corn-soybean meal type diet with normal Ca and P levels,and the others in T1~T3 groups were fed corn-soybean meal type diet with low Ca and P levels+0,1000 and 1500 FIU/kg phytase.The experiment was divided into two stages:1~21 days and 22~42 days.RESULTS:The body weight of broilers in control group and T3 group on 42 days was significantly higher than that in T1 group(P<0.05),and the average daily gain of broilers in T3 group on 22~42 days and 1~42 days was significantly increased by 8.01%and 5.05%compared with that in T1 group(P<0.05),respectively.Compared with other groups,feed remuneration of broilers in T3 group was significantly increased by 3.3%,3.09%and 3.73%during 22~42 days(P<0.05),respectively.The apparent digestibility of Ca in control group and T3 group was significantly higher than that in T1 and T2 groups(P<0.05),the deposition rates of dry matter,nitrogen and Ca in T3 group were significantly higher than those in control group and T1 group(P<0.05),and the deposition of phosphorus in T3 group was the highest(P<0.05).The apparent digestibility of methionine and threonine in T1 group was significantly lower than that in T3 group(P<0.05),while the ileal apparent digestibility of leucine,isoleucine,glycine and alanine in T1 group had the lowest values(P<0.05).Conclusions:The supplementation of phytase in corn-soybean meal low calcium and phosphorus diet can effectively improve the nutritional value of calcium and phosphorus and the metabolic rate of dry matter,nitrogen and amino acid.The higher dose(1500 FTU/kg)had the greatest benefit on feed return and amino acid digestion of broilers in late growth period.