维生素C对大鲵消化系统结构和功能的影响

本试验在大鲵基础饲料中添加不同梯度的维生素C,探究其对机体消化系统各器官结构和功能的影响。方法]以鱼粉、鸡肉粉等为蛋白源,鱼油为脂肪源配制大鲵基础饲料,基础饲料中分别添加0 mg/kg(D1)、150mg/kg(D2)、300mg/kg(D3)、450 mg/kg(D4)、600mg/kg(D5)和750mg/kg(D6)的维生素C(维生素C磷酸酯,35%含量),配制成6种等氮等脂的试验饲料,饲喂初始体质量为(34.14±0.15)g 的试验幼鲵。结果]结果表明：随维生素C添加量的增加,幼鲵胃蛋白酶、H⁺-K⁺-ATP酶活性均在D3组达到最高,通过对胃切片肌层厚度、绒毛高度等统计,添加300mg/kg维生素C比添加0、600mg/kg更有利于大鲵胃部发育(P＜0.05)；肠道糜蛋白酶、脂肪酶及Na⁺-K⁺-ATP酶活力均呈先升后趋于平稳趋势,在D4组达到最高(P＜0.05),对肠道淀粉酶无显著性影响(P＞0.05),通过对肠道切片肌层厚度、绒毛高度统计,添加300mg/kg维生素C比添加0、600mg/kg更有利于大鲵肠道发育；胰腺糜蛋白酶及脂肪酶活力均呈先升后趋于平稳趋势,分别在D3、D4组达到最大(P＜0.05),对胰腺淀粉酶无显著性影响(P＞0.05)；肝脏MDA、AST和ALT活性均呈先降后升趋势,并均在D3组达到最低,而CAT、T-SOD、ACP及AKP则呈先升后降的趋势,CAT、T-SOD、ACP在D4组达最高峰,AKP在D3组达最高,通过对肝脏切片发现,添加300mg/kg维生素C相较于添加0、600mg/kg炎性细胞浸润现象明显减少,肝巨噬细胞数量明显增加。结论] 综上所述,适量的维生素C可有效的改善大鲵消化道的结构,提高消化酶活性,增强肝脏抗氧化能力,保护肝脏健康。

Effects of vitamin C on the structure and function of the digestive system of Andrias davidianus

In this experiment, different gradients of vitamin C were added to the basic diet of Andrias davidianus to explore its effect on the structure and function of digestive system organs. Methods] Fish meal and chicken meal were used as protein source and fish oil as fat source to prepare basic diet for giant salamander. Six kinds of isonitrogenous and isolipidemic experimental diets were prepared by adding 0 mg / kg (D1), 150 mg / kg (D2), 300 mg / kg (D3), 450 mg / kg (D4), 600 mg / kg (D5) and 750 mg / kg (D6) of vitamin C (35%) into the basic diet, The experimental young salamanders with initial body weight of (34.14 ± 0.15) g were fed. Results] The results showed that: with the increase of vitamin C, the activities of pepsin and H ⁺ - K ⁺ - ATPase of juvenile salamander reached the highest in D3 group. According to the statistics of the thickness of gastric muscle layer and villus height, adding 300mg / kg vitamin C was more conducive to the development of stomach than adding 0 and 600mg / kg vitamin C (P < 0.05); The activities of chymotrypsin, lipase and Na ⁺ - K ⁺ - ATPase increased at first and then tended to be stable, and reached the highest in D4 group (P < 0.05), but had no significant effect on intestinal amylase (P > 0.05). According to the statistics of muscle layer thickness and villus height of intestinal slices, adding 300mg / kg vitamin C was more conducive to the intestinal development of Andrias davidianus than adding 0 and 600mg / kg vitamin C; The activities of chymotrypsin and lipase increased at first and then tended to be stable, reaching the maximum in D3 and D4 groups (P < 0.05), but had no significant effect on pancreatic amylase (P > 0.05); The activities of MDA, AST and ALT in liver decreased first and then increased, and reached the lowest in D3 group, while cat, T-SOD, ACP and AKP increased first and then decreased. Cat, T-SOD and ACP reached the peak in D4 group, and AKP reached the highest in D3 group, The number of liver macrophages increased significantly Conclusion] in conclusion, appropriate amount of vitamin C can effectively improve the structure of digestive tract, increase digestive enzyme activity, enhance liver antioxidant capacity and protect liver health.