摘要
本试验旨在研究高糖饲料及添加缩合单宁(CT)对花鲈生长性能、体成分、血清代谢物、肠道短链脂肪酸含量及激素基因表达的影响.选取480尾初始体重为(10.85±0.02)g的健康花鲈,随机分为3组,每组4个重复,每个重复40尾鱼.3组分别饲喂常规饲料(含20.0％面粉,G1组)、高糖饲料(含45.8％面粉,G2组)和添加CT的高糖饲料(含45.8％面粉和0.1％CT,G3组).试验期56 d.结果表明:1)与G1组相比,G2组花鲈终末体重、增重率和特定生长率显著降低(P＜0.05),饲料系数、肥满度、肝体比和脏体比显著提高(P＜0.05);与G2组相比,G3组终末体重、增重率和特定生长率显著提高(P＜0.05),饲料系数显著降低(P＜0.05).2)与G1组相比,G2组和G3组花鲈全鱼水分、粗蛋白质和粗灰分含量显著降低(P＜0.05).3)在投喂后1 h,G2组花鲈血清葡萄糖含量显著高于G1组和G3组(P＜0.05);而在投喂后3和6 h,各组之间血清葡萄糖含量无显著差异(P＞0.05).G2组花鲈血清谷草转氨酶活性和高密度脂蛋白胆固醇含量显著高于G1组和G3组(P＜0.05),G1组和G3组上述指标无显著差异(P＞0.05).4)各组花鲈肠道中乙酸、丁酸和总短链脂肪酸含量由高到低依次为G1组＞G3组＞G2组,且组间差异显著(P＜0.05).5)G2组花鲈肠道中胰高血糖素样肽-1(GLP-1)、胰高血糖素样肽-2(GLP-2)、钠依赖性葡萄糖共转运载体1(SGLT1)、钠依赖性葡萄糖共转运载体2(SGLT2)和葡萄糖转运载体2(GLUT2)的mRNA相对表达量显著低于G1组和G3组(P＜0.05),G2组肠道中YY肽(PYY)的mRNA相对表达量显著高于G1组和G3组(P＜0.05),G1组和G3组之间上述指标均无显著差异(P＞0.05).综上所述,高糖饲料可提高花鲈血清葡萄糖含量,诱导肝脏损伤,降低肠道短链脂肪酸含量以及胰高血糖素样肽和葡萄糖转运载体基因的表达量,抑制花鲈的生长和营养物质沉积.高糖饲料中添加0.1％CT可修复花鲈肝脏损伤,通过调控肠道激素的基因表达,降低血清葡萄糖含量,提高花鲈生长性能.
Abstract
This study was conducted to investigate the effects of high sugar diet and condensed tannin(CT)supplementation on growth performance,body composition,serum metabolites,intestinal short-chain fatty acid contents and hormone gene expression of sea bass(Lateolabrax maculatus).A total of 480 healthy sea bass with an initial body weight of(10.85±0.02)g were randomly divided into 3 groups with 4 replicates per group and 40 fish per replicate.Sea bass in the three groups were fed conventional diet(containing 20.0％flour,G1 group),high sugar diet(containing 45.8％flour,G2 group)and high sugar diet supplemented with CT(con-taining 45.8％flour and 0.1％CT,G3 group),respectively.The experiment lasted for 56 days.The results showed as follows:1)compared with G1 group,the final body weight,weight gain rate and specific growth rate of sea bass in G2 group were significantly decreased(P＜0.05),and the feed coefficient,condition fac-tor,hepatosomatic index and viscerosomatic index were significantly increased(P＜0.05).Compared with G2 group,the final body weight,weight gain rate and specific growth rate in G3 group were significantly in-creased(P＜0.05),and the feed coefficient was significantly decreased(P＜0.05).2)Compared with Gl group,the contents of moisture,crude protein and crude ash in the whole body of sea bass in G2 and G3 groups were significantly decreased(P＜0.05).3)At 1 h after feeding,the serum glucose content of sea bass in G2 group was significantly higher than that in G1 and G3 groups(P＜0.05);at 3 and 6 h after feeding,there was no significant difference in serum glucose content among all groups(P＞0.05).The serum glutamic oxaloacetic transaminase activity and high-density lipoprotein cholesterol content of sea bass in G2 group were significantly higher than those in G1 and G3 groups(P＜0.05),but there were no significant differences in the above indices between G1 and G3 groups(P＞0.05).4)The contents of acetic acid,butyric acid and total short-chain fatty acid in intestine of sea bass in all groups were in the order of G1 group＞G3 group＞G2 group from high to low,and the differences among groups were all significant(P＜0.05).5)The mRNA relative ex-pression levels of glucagon-like peptide-1(GLP-1),glucagon-like peptide-2(GLP-2),sodium-dependent glucose cotransporter 1(SGLT1),sodium-dependent glucose cotransporter 2(SGLT2)and glucose transporter 2(GLUT2)in intestine of sea bass in G2 group were significantly lower than those in G1 and G1 groups(P＜0.05),the YY peptide(PYY)mRNA relative expression level in intestine in G2 group was significantly high-er than that in G1 and G3 groups(P＜0.05),but there were no significant differences between G1 and G3 groups(P＞0.05).In conclusion,the high sugar diet can increase the serum glucose content,induce the liver injury,reduce the intestinal short-chain fatty acid content and expression of glucagon-like peptide and glucose transporter genes,and inhibit the growth and nutrient deposition of sea bass.The supplementation of 0.1％CT in the high sugar diet can repair the liver injury,reduce the serum glucose content by regulating the gene ex-pression of intestinal hormone,and improve the growth performance of sea bass.[Chinese Journal of Animal Nutrition,2024,36(8):5254-5268]
维普
万方数据