发酵菜籽粕对黄颡鱼表观消化率、肝脏及肠道健康的影响

FERMENTED RAPESEED MEAL ON APPARENT DIGESTIBILITY, LIVER ANDINTESTINAL HEALTH OF YELLOW CATFISH (TACHYSURUS FULVIDRACO)

为探究发酵菜籽粕对黄颡鱼的饲料表观消化率、肝脏及肠道健康的影响,实验以黄颡鱼(Tachysurus fulvidraco)为研究对象,共设置3组饲料,分别为对照组(Control)、未发酵菜籽粕组(URSM)和发酵菜籽粕组(FRSM),养殖实验共持续7周。研究结果表明,FRSM组的增重率(WGR)显著高于USRM组(P<0.05),而饲料系数(FCR)和肝体比(HSI)显著低于URSM组(P<0.05)。与未发酵菜籽粕原料相比,黄颡鱼对发酵菜籽粕原料的干物质、粗蛋白、粗脂肪和能量的表观消化率均增加。肝脏组织结构结果表明,URSM组黄颡鱼肝细胞空泡化的相对面积显著高于对照组和FRSM组(P<0.05)。肠道组织结构及紧密连接相关基因试验结果表明,3组间的黄颡鱼肠道绒毛宽度无显著性差异(P>0.05),而FRSM组黄颡鱼的绒毛长度和肠道zo-1和zo-2的mRNA表达水平显著高于URSM组(P<0.05)。炎症因子相关基因测定结果表明,与URSM组相比,FRSM组黄颡鱼肝脏tnf-α、tnf-β和il-1β的mRNA表达水平显著下调,肠道tnf-α和il-6的mRNA表达水平显著下调,而肠道il-10和tgf-β的mRNA表达水平显著上调。与对照组相比,饲料添加未发酵菜籽粕显著增加了黄颡鱼肝脏和肠道的MDA含量(P<0.05),降低了总抗氧化能力(P<0.05),引发肝脏和肠道氧化应激。而饲料添加发酵菜籽粕减轻了菜籽粕导致的黄颡鱼肝脏和肠道氧化损伤。凋亡相关基因检测结果发现,与对照组相比,饲料添加未发酵菜籽上调了黄颡鱼肝脏和肠道促凋亡基因bax、p53、caspase3、caspase9和mdm2的表达水平,但是下调了bcl2的mRNA表达(P<0.05)。而饲料添加发酵菜籽粕明显改善了未发酵菜籽粕导致的促凋亡现象。研究表明,菜籽粕经发酵后添加至饲料中,可以减轻未发酵菜籽粕导致的黄颡鱼肝脏和肠道炎症反应、氧化损伤及细胞凋亡,从而改善黄颡鱼肝脏和肠道健康。研究为深入探讨发酵菜籽粕对鱼类肝脏和肠道健康的改善作用提供了理论依据,对于发酵菜籽粕在鱼类生产中的应用具有重要意义。

In order to investigate the effects of fermented rapeseed meal on apparent digestibility,liver and intestinal health of yellow catfish(Tachysurus fulvidraco),the experiment utilized yellow catfish as the research object.Three groups were established,namely the Control(reference diet group),URSM(unfermented rapeseed meal group)and FRSM(fermented rapeseed meal group)respectively.The feeding experiment lasted for 7 weeks.The results showed that the weight gain rate(WGR)of the FRSM group were significantly higher than those of the USRM group(P<0.05),while the feed conversion ratio(FCR)and hepatosomatic index(HSI)were significantly lower than those of the URSM group(P<0.05).Compared with unfermented rapeseed meal materials,the apparent digestibility of dry matter,crude protein,crude fat and gross energy of the fermented rapeseed meal materials were all increased.The relative area of hepatic vacuoles in URSM group was significantly higher than that in control group and FRSM group(P<0.05).There was no significant difference in the villi width of yellow catfish among the three groups(P>0.05),while the villi height of the FRSM group was significantly higher than that in the URSM group(P<0.05).The FRSM diets reduced the upregulation of mRNA expression of liver pro-inflammatory factor-related genes(tnf-α,tnf-β,il-1βand il-6)and intestinal tnf-αand il-6 induced by rapeseed meal.In addition,the FRSM diets alleviated the downregulation of liver anti-inflammatory factors il-10 and intestinal il-10 and tgf-βinduced by unfermented rapeseed meal.Compared with the control group,the URSM diets significantly increased the Malondialdehyde(MDA)content(P<0.05),decreased the total antioxidant capacity(P<0.05),and induced oxidative stress in the liver and intestine.the FRSM diets alleviated the oxidative damage caused by rapeseed meal of liver and intestine of yellow catfish.The detection of apoptosis-related genes showed that the URSM diets up-regulated the expression levels of pro-apoptotic genes(bax,p53,caspase3,caspase9 and mdm2)in the liver and intestine of yellow catfish,but down-regulated the expression levels of bcl2 mRNA expression(P<0.05)compared with the control group.Therefore,the FRSM diets improved the pro-apoptotic phenomenon caused by unfermented rapeseed meal.This study shows that fermented rapeseed meal added to the diet can reduce the inflammatory response,oxidative damage and cell apoptosis in the liver and intestine of yellow catfish caused by unfermented rapeseed meal,thereby improving the liver and intestinal healthy of yellow catfish.This study provides a basis for in-depth exploration of the effect of fermented rapeseed meal on the improvement of liver and intestinal health of fish,and it holds significant implications for the application of fermented rapeseed meal in fish production.