低磷日粮添加植酸酶对肉鸡营养学效应影响研究

A Study on Nutriology Effects of Subnormal Phosphorus Dietary Supplementation of Microbial Phytase on Broilers

280 只同日出壳的艾维茵肉鸡,随机分成4 组,饲喂玉米———米糠———豆饼型日粮,采用饲养试验、代谢试验、生化指标分析等来研究低磷日粮添加植酸酶与磷酸氢钙,对其生长性能、组织中酶活和矿物质含量及蛋白质利用率影响。Ⅰ组为低磷组,Ⅱ组为添加磷酸氢钙组,Ⅲ、Ⅳ组为添加375,750 u/kg 的植酸酶组。试验结果表明:(1) 添加植酸酶可提高钙、磷及蛋白质利用率,降低粪中磷的排泄量。(2) 各组肝及胫骨中铜、锌、钙、磷含量差异不显著,但随植酸酸添加量增加有提高的趋势。(3) 低磷日粮中添加750 u/kg 植酸酶,完全可取代磷酸氢钙,降低饲料成本,提高经济效益。

same-aged young broilers, which were selected as experimental animals, were divided into four groups randomly. Feeding experiment, metabolic trial and biochemical indexes analysis were done to study the effects on the growth performance, the activity of alkaline phosphatase in serum, the content of mineral elements in tissue and the utilization ratio of protein on base of maize meal-rice bran-soybean meal diet. Group I was fed with subnormal available phosphorus diet only containing 50% available phosphorus contrast to normal as negative control. Group Ⅱ was fed with normal diet as positive control. Group Ⅲ,Ⅳ were fed with low phosphorus diet with additional 375u/kg,750u/kg phytase respectively. The results showed as following:(1)Phytase added to subnormal diet improved the utilization ratio of calcium, phosphorus, phytate-phosphorus and protein, reduced the excretion of phosphorus in feces, increased feed conversion rate (FCR), and decreased disease ratio. (2)The content of Cu, Zn, Ca, P in liver and shin of the four groups had no significant difference, but showed a heightening tendency with the increasement of phytase supplementation. (3)The 0.03% phytase (750u/kg) added to subnormal phosphorus diet could replace dicalcium phosphate completely increase feed formular scope, reduce feed cost and improve economic benefits.