饲料中添加丁酸钠对草鱼生长、消化酶活性、血清生化指标和肠道组织学的影响

Effects of sodium butyrate on growth,digestive enzyme activity,serum biochemical indices and intestinal histology of grass carp(Ctenopharyngodon idella)

为了探究饲料中补充不同水平丁酸钠对草鱼生长性能、肠道消化酶活性、血清生化指标和肠道组织形态的影响,分别添加0 mg/kg (SB0)、1 000 mg/kg (SB1)、2 000 mg/kg(SB2)和3 000 mg/kg (SB3)的微囊丁酸钠(含50%丁酸钠)至基础饲料中,设计4组等氮等脂的实验饲料。选取300尾体质健康的草鱼(10.0±0.1) g,分成4组,每组3个重复,每个重复25尾鱼,放置在水泥池中养殖8周。结果显示,各组草鱼增重率为273.7%~279.9%,饲料系数为1.55~1.60,饲料中补充丁酸钠对草鱼生长性能和体成分无显著影响。与对照组相比,添加不同水平的丁酸钠均显著提高了肠道蛋白酶活性和血清超氧化物歧化酶(SOD)活性,降低了血清谷草转氨酶(AST)活性,SB1组血清碱性磷酸酶(AKP)活性显著升高,而SB2和SB3组血清谷丙转氨酶(ALT)活性显著降低。各组肠道淀粉酶活性、血清酸性磷酸酶(ACP)、甘油三酯(TG)、葡萄糖(GLU)、总蛋白(TP)和D-乳酸(D-LA)无显著差异。在肠道组织学方面,各丁酸钠补充组肠道绒毛高度和SB1、SB2组肌层厚度显著高于对照组,而各组间肠道绒毛宽度没有显著差异;在肝脏组织学方面,各组间无明显可见差异。研究表明,在饲料中添加不同水平的丁酸钠,对草鱼增重率和饲料利用无显著促进作用,但可提高肠道消化酶活性,改善肠道组织形态。本研究可为水产饲料中合理利用丁酸钠提供理论依据。

The study investigated the effects of dietary supplementation of sodium butyrate on growth performance,intestinal digestive enzyme activity,serum biochemical indices and intestinal morphology of Ctenopharyngodon idella.Based on the control diet(SB0),microencapsulated sodium butyrate(containing 50%sodium butyrate)was added at the levels of 0 mg/kg(SB0),1000 mg/kg(SB1),2000 mg/kg(SB2)and 3000 mg/kg(SB3)to form four iso-nitrogenous and iso-lipidic diets,respectively.A total of 300 C.idella juvenile(10.0±0.1)g were randomly divided into 4 groups with 3 replicates(cages)and 25 fish per replicate.The fish were fed the four diets in indoor cement ponds for 8 weeks.The results showed that the weight gain and feed conversion ratio of all groups were 273.7%-279.9%,1.55-1.60,and dietary sodium butyrate did not significantly affect the growth performance and body composition of C.idella(P>0.05).Compared to the control group(SBO),dietary sodium butyrate significantly increased intestinal protease activity and serum superoxide dismutase(SOD)activity(P<0.05),and decreased serum aspartate aminotransferase(AST)activity(P<0.05).In addition,serum alkaline phosphatase(AKP)activity was increased significantly in SB1 group(P<0.05),while serum alanine aminotransferase(ALT)activity was decreased significantly in SB2 and SB3 groups(P<0.05).There was no significant difference in intestinal amylase activity,serum acid phosphatase(ACP),triglyceride(TG),glucose(GLU),total protein(TP)and Dlactic acid(D-LA)among the four groups(P>0.05).In intestinal and hepatic histology,the supplementation of sodium butyrate significantly increased the height of intestinal villi(P<0.05),and the thickness of muscle layer in SB1 and SB2 groups was significantly higher than that in the control group(P<0.05),but no significant differences in intestinal villus width and hepatic histology were observed among the four groups(P>0.05).In conclusion,dietary supplementation of sodium butyrate did not significantly promote the growth performance of C.idella,but increased the activity of intestinal digestive enzymes and improved the morphology of intestinal tissue.