不同磷酸二氢钙含量饲料中添加中性植酸酶对异育银鲫生长及营养物质表观消化率、沉积率和血浆生化指标的影响

Effects of Supplementation of Neutral Phytase in Diets with Various Monocalcium Phosphate Contents on Growth,Apparent Digestibility and Deposition Rates of Nutrients and Plasma Biochemical Indices of Allogyogenetics Silver Crucian Carp (Carassius auratus g

本试验研究了在不同磷酸二氢钙含量饲料中添加中性植酸酶对异育银鲫生长及营养物质表观消化率、沉积率和血浆生化指标的影响。配制磷酸二氢钙含量为1.5%的正对照饲料和磷酸二氢钙含量分别为1.0%、0.5%的负对照饲料,在含1.0%磷酸二氢钙饲料中分别添加400、800 IU/kg中性植酸酶,在含0.5%磷酸二氢钙饲料中添加400 IU/kg中性植酸酶,共配制成6种试验饲料,饲喂初始体重为(39.0±3.0)g的异育银鲫10周。每种饲料设3个重复,每个重复放养15尾鱼。结果显示:在不添加中性植酸酶的情况下,随磷酸二氢钙添加量增加,鱼体增重率,干物质、磷表观消化率,蛋白质、灰分沉积率,全鱼磷含量均显著增加(P<0.05),血浆碱性磷酸酶(ALP)活性显著降低(P<0.05);在含1.0%磷酸二氢钙饲料中添加800 IU/kg中性植酸酶显著提高了增重率(P<0.05),同时显著提高了蛋白质、灰分和磷沉积率,干物质和磷表观消化率,全鱼磷含量,椎骨钙含量及血浆甘油三酯(TG)含量(P<0.05),显著降低了血浆ALP活性(P<0.05);在含0.5%、1.0%磷酸二氢钙饲料中添加400 IU/kg中性植酸酶均显著提高了磷表观消化率和磷沉积率(P<0.05);在不同磷酸二氢钙含量饲料中添加中性植酸酶对血浆总蛋白(TP)、白蛋白(ALB)、钙、磷含量无显著影响(P>0.05)。以上结果表明,在磷酸二氢钙含量为1.0%的饲料中添加800 IU/kg中性植酸酶可促进异育银鲫的生长,提高干物质和磷的表观消化率,800 IU/kg中性植酸酶在底物充足条件下可代替0.5%磷酸二氢钙的添加。

The present study was conducted to evaluate the effects of supplementation of neutral phytase in diets with various monocalcium phosphate（M CP） contents on growth,apparent digestibility and deposition rates of nutrients and plasma biochemical indices of allogyogenetics silver crucian carp（Carassius auratus gibelio）.Six diets were prepared to fed allogyogenetics silver crucian carp with the initial body weight of（39.0 ± 3.0） g for10 weeks,which were 1.5%,1.0% and 0.5% M CP diets,and 1.0% M CP＋ 400 IU/kg neutral phytase diet,1.0% M CP＋ 800 IU/kg neutral phytase diet and 0.5% M CP ＋ 400 IU/kg neutral phytase diet,respectively.Each diet had 3 replicates and each replicate had 15 fish.The results showed as follows：when diets no adding neutral phytase,weight gain rate（W GR）,the apparent digestibility of dry matter（DM） and phosphorus（P）,the deposition rates of protein and ash,and whole body P content were significantly increased（P〈0.05）,but plasma alkaline phosphatase（ALP） activity was significantly decreased（P〈0.05）,with the increase of dietary M CP content.Supplementation of 800 IU/kg neutral phytase in the 1.0% M CP diet could significantly improve the W GR（P〈0.05） and reached the similar level to the group of 1.5% M CP diet;moreover,it could significantly increase the deposition rates of protein,ash and P,the apparent digestibility of DM and P,whole body P content,vertebral calcium（Ca） content and plasma triglycerides（TG） content,but significantly decrease the plasma ALP activity（P〈0.05）.Supplementation of 400 IU/kg neutral phytase in 0.5%or 1.0% M CP diets could significantly promote P apparent digestibility and P deposition rate（P〈0.05）.There were no significant differences in plasma total protein（TP）,albumin（ALB）,P and Ca contents among all groups（P〉0.05）.Results above showthat the supplementation of 800 IU/kg neutral phytase in 1.0% M CP diet can improve the growth and increase the apparent digestibility of DM and P of allogyogenetics silver crucian carp,and 800 IU/kg neutral phytase can be used to replace 0.5% M CP in the diet under sufficient substrates supply.