不同糖源对方斑东风螺生长、饲料利用和消化酶活性的影响

以鱼粉、酪蛋白和明胶为蛋白源,分别以20%添加水平的葡萄糖、糊精、蔗糖、玉米淀粉、小麦淀粉和马铃薯淀粉为糖源,配制成6种不同糖源的等氮等能饲料,研究不同糖源对方斑东风螺幼螺生长性能、饲料利用、消化酶活性、糖原含量、蛋白质含量及肉壳比的影响。结果表明:方斑东风螺幼螺的增重率、特定生长率、饲料系数、蛋白质效率,消化酶活性、糖原含量、蛋白质含量及肉壳比均受到糖源种类的显著影响(P<0.05)。增重率、特定生长率从高至低依次为小麦淀粉组、玉米淀粉组、马铃薯淀粉组、糊精组、葡萄糖组、蔗糖组;饲料系数及蛋白质效率均以小麦淀粉组表现最好,与马铃薯淀粉组和玉米淀粉组无显著性差异,显著优于糊精组、葡萄糖组及蔗糖组。消化酶活性的分析结果表明,淀粉酶活性最高的是蔗糖组和小麦淀粉组,糊精组次之,葡萄糖组和马铃薯淀粉组的淀粉酶活性最低;各处理组脂肪酶活性存在显著差异,从高至低分依次为马铃薯淀粉组>小麦淀粉组>糊精组>玉米淀粉组>蔗糖组、葡萄糖组;蛋白酶活性以小麦淀粉组最高,其次为蔗糖组,其他糖源组并无显著差异;而内脏团糖原和肌糖原含量,除了葡萄糖组外,其他各组差异不显著(P>0.05);蛋白质含量以葡萄糖组最高,小麦淀粉组最低,而肉壳比则刚好相反,以小麦淀粉组和玉米淀粉组最高,葡萄糖组最低。以生长、饲料利用率和消化酶活性为评价指标,方斑东风螺饲料中采用小麦淀粉作为糖源效果最优。

Effect of Dietary Carbohydrate Sources on Growth, Feed utilization and Digestive Enzymes Activities of Juvenile Ivory Shell Babylonia areolate

An experiment was conducted to investigate the effect of different carbohydrate sources on growth,feed utilization and digestive enzymes activities of juvenile ivory shell,Babylonia areolate.Triplicate groups of juvenile ivory shells(initial weight,511.68±0.32mg) were fed six isonitrogenous and isoenergetic diets which contained 20% glucose,dextrin,sucrose,corn starch,wheat starch or potato starch,respectively.After a 12-week feeding trial,the growth performance,feed utilization,digestive enzymes activities,glycose content and crude protein in soft body,and soft body to shell ratio(SB/S ratio) were measured.The results showed that weight gain(WG),specific growth rate(SGR),feed conversion rate(FCR),protein efficiency rate(PER),digestive enzyme activities,glycose content,crude protein and SB/S ratio were significantly affected by the dietary carbohydrate sources.Wheat starch group showed the highest WG and SGR,with the sequence from high to low were wheat starch,corn starch,potato starch,dextrin,glucose and sucrose.The best FCR and PER were observed both in wheat starch group,which was not significantly different between potato starch and corn starch groups,but significantly better than dextrin,glucose and sucrose groups.From the perspective of the digestive enzymes activities,the highest amylase activities were observed in sucrose and wheat starch groups,followed by dextrin group,and the lowest amylase activities were observed in glucose and potato starch groups.Lipase activities in all treatments were significantly affected by the dietary carbohydrate sources,the sequence from high to low was the potato starch,wheat starch,dextrin,corn starch,sucrose and glucose.The pepsin activity in wheat starch group was the highest,followed by sucrose group,and there was no significant difference with the other groups.However,no significant differences were found in glycose content among all treatments except glucose group.Crude protein in soft body was the highest in glucose group,and the lowest was observed in wheat starch group,whereas the SB/S ratio showed an opposite result that the highest ratio were observed in wheat starch and corn starch groups,and the lowest ratio was in glucose group.Based on the growth performance,feed utilization and digestive enzyme activities,it indicated that the optimal dietary carbohydrate source for juvenile ivory shell was wheat starch.