中文摘要：

本试验旨在探究普安银鲫早期发育过程中消化酶活性变化及外源维生素C对其的影响。采用普安银鲫的成熟卵，以兴国红鲤（ Cyprinus carpio）进行异源人工干法授精，分为2组，孵化水体维生素C浓度分别为0和30 mg/L，分别在成熟卵、受精卵、原肠中期、晶体出现期、混合营养期及外源营养期采样，测定消化酶活性的变化。结果表明：1）维生素C能促进普安银鲫早期发育过程中蛋白质的沉积。2）成熟卵经异源授精后淀粉酶活性显著提高（P＜0.05）。3）从原肠中期到外源营养期，胰蛋白酶和淀粉酶活性随发育呈上升趋势，各时期间差异均显著（P＜0.05）；胃蛋白酶、脂肪酶和纤维素酶活性从原肠中期到晶体出现期无显著上升（P＞0.05），而在晶体出现期至外源营养期这3种酶活性呈上升趋势，各时期间差异均显著（P＜0.05）。4）30 mg/L的维生素C溶液浸泡能显著提高胰蛋白酶、淀粉酶、脂肪酶和胃蛋白酶活性（P＜0.05），但对纤维素酶活性无显著影响（P＞0.05）。结果提示，普安银鲫成熟卵经异源授精后淀粉酶优先发挥作用，分解卵黄中的碳水化合物为胚胎发育迅速提供能量；胰蛋白酶、淀粉酶、胃蛋白酶和脂肪酶分解卵黄物质，在器官形成及仔鱼发育中起着主要作用；30 mg/L的维生素C能显著提高胰蛋白酶、淀粉酶、胃蛋白酶和脂肪酶活性，并促进蛋白质的沉积。

英文摘要：

This experiment was conducted to study the variation of digestive enzyme activities of Carassius auratus during early development and the effects of exogenous vitamin C.Mature eggs from Carassius auratus were selected and cross-fertilized using Cyprinus carpio by the method of artificial dried fertilization.The eggs were divided into two groups, and the vitamin C concentration in water for incubation was 0 and 30 mg/L, respectively.Samples were collected at mature eggs, fertilized eggs, mid-gastrula, crystal appear, mixed nutrition and exogenous nutrition stages to determine the variation of digestive enzyme activities.The results showed as follows：1） vitamin C was contributed to the deposition of protein in Carassius auratus during early devel-opment.2） After cross-fertilization, the activity of amylase was significantly higher than that of mature eggs （ P〈0.05） .3） From mid-gastrula stage to exogenous nutrition stage, the activities of trypsin and amylase were increased with development, the differences among stages were significant （ P〈0.05）;the activities of pepsin, lipase and cellulase had no obvious rise from mid-gastrula stage to crystal appear stage （ P〉0.05 ） , but were raised from crystal appear stage to exogenous nutrient stage, the differences were significant （P〈0.05）.4） The inhabitation in 30 mg/L vitamin C solution significantly increased the activities of trypsin, amylase, lipase and pepsin, but had no obvious effect on cellulase activity.The results indicate that amylase priority decompo-sition carbohydrates in yolk of mature eggs from Cyprinus carpio to provide energy for embryonic development rapidly after cross-fertilization;trypsin, amylase, pepsin and lipase play major roles in decomposition yolk nutrients, organ formation and the development of larvae;30 mg/L vitamin C solution can significantly increase the activities of trypsin, amylase, pepsin and lipase, and elevate the deposition of protein.