酵母水解物对青鱼幼鱼生长性能、肌肉品质及肝胰脏抗氧化指标和组织形态的影响

Effects of Yeast Hydrolysate on Growth Performance,Muscle Quality,Hepatopancreases Antioxidant Indexes and Tissue Morphology of Juvenile Black Carp(Mylopharyngodon piceus)

本试验旨在研究饲料中添加不同水平酵母水解物(YHY)对青鱼(Mylopharyngodon pi ceus)幼鱼生长性能、全鱼及肌肉氨基酸组成以及肝胰脏抗氧化指标和组织形态的影响。在基础饲料中分别添加0、0.5%、1.0%、1.5%、2.0%和2.5%的YHY,配制成6种等氮等能的试验饲料[分别命名为YHY0(对照)、YHY0.5、YHY1.0、YHY1.5、YHY2.0和YHY2.5]。选择初始体重为(5.53±0.14)g的青鱼幼鱼720尾,随机分为6组,每组4个重复,每个重复30尾鱼,在室内循环水系统中进行为期8周的养殖试验。结果表明:1)青鱼幼鱼的特定生长率(SGR)呈先上升后下降的趋势,蛋白质效率(PER)上升后逐渐平缓。YHY1.5和YHY2.0组SGR显著高于对照组(P<0.05),且与YHY2.5组相比无显著差异(P>0.05);YHY1.5、YHY2.0和YHY2.5组PER显著高于对照组(P<0.05)。2)饲料中添加不同水平YHY对青鱼幼鱼全鱼的干物质、粗蛋白质和粗灰分含量无显著影响(P>0.05)。全鱼粗脂肪含量呈上升趋势,在YHY2.5组达到最大,显著高于对照组(P<0.05)。YHY添加水平对青鱼幼鱼肌肉的干物质、粗蛋白质和粗脂肪含量无显著影响(P>0.05)。YHY2.0和YHY2.5组肌肉粗灰分含量显著高于对照组(P<0.05)。3)与对照组相比,饲料中添加YHY显著增加了青鱼幼鱼全鱼以及肌肉中的必需氨基酸以及呈味氨基酸含量(P<0.05),同时,显著提高了肌肉中各种氨基酸的氨基酸价(AAS)、化学价(CS)以及必需氨基酸指数(EAAI)(P<0.05)。4)青鱼幼鱼肝胰脏总抗氧化能力(T AOC)及总超氧化物歧化酶(T SOD)活性均呈先升高后降低的变化趋势。在YHY添加水平为1.5%时,青鱼幼鱼肝胰脏的T AOC及T SOD活性均达到最高,显著高于对照组(P<0.05)。YHY对青鱼幼鱼肝胰脏过氧化氢酶(CAT)活性无显著影响(P>0.05),有利于改善肝胰脏细胞空泡化现象。综上所述,基于SGR和PER的数据分析,在饲料中添加1.57%~2.02%的YHY能提高青鱼幼鱼的生长性能,同时,YHY能提高青鱼幼鱼全鱼及肌肉的氨基酸含量、肝胰脏抗氧化指标,改善肌肉品质,并且不会对青鱼幼鱼的肝胰脏组织形态产生不良影响。

This experiment was conducted to estimate the effects of dietary levels of yeast hydrolysate(YHY)on growth performance,whole body and muscle amino acid composition,hepatopancreases antioxidant indexes and tissue morphology of juvenile black carp(Mylopharyngodon piceus).The YHY of 0,0.5%,1.0%,1.5%,2.0%and 2.5%were added to a basic diet,and six isonitrogenous and isoenergetic diets were prepared[named YHY0(control),YHY0.5,YHY1.0,YHY1.5,YHY2.0 and YHY2.5,respectively].A total of 720 juvenile black carps with an initial average body weight of(5.53±0.14)g were randomly divided into six groups with four replicates per group and 30 black carps per replicate.The experiment was carried out in the circulating water system for 8 weeks.The results showed as follow:1)the specific growth rate(SGR)of ju venile black carp increased first and then decreased,and the protein efficiency(PER)increased and then grad ually smooth.YHY1.5 and YHY2.0 groups had significantly higher SGR compared with the control group(P<0.05),and there was no significant difference compared with the YHY2.5 group(P>0.05);PER in the YHY1.5,YHY2.0 and YHY2.5 groups was significantly higher than that in the control group(P<0.05).2)Dietary different levels of YHY had no significant influences on dry matter,crude protein and ash contents of whole body(P>0.05).The crude lipid of whole body showed an upward trend and reached the maximum in the YHY2.5 group,which was significantly higher than that in the control group(P<0.05).Dietary different levels of YHY had no significant influence on day matter,crude protein and crude lipid contents of juvenile black carp muscle(P>0.05).The ash contents in the YHY2.0 and YHY2.5 groups was significantly higher than that in the control group(P<0.05).3)The essential amino acids and flavor amino acids contents of whole body and muscle in all supplemental groups were significantly higher than those in control group(P<0.05).At the same time,the amino acid score(AAS),chemical score(CS)and essential amino acid index(EAAI)were significantly improved with the increasing supplementation level of YHY(P<0.05).4)The to tal antioxidant capacity(T AOC)and total superoxide dismutase(T SOD)activity of juvenile black carp were increased firstly and then decreased.And the T AOC and T SOD activity in the 1.5%group reached the high est,which was significantly higher than that in the control group(P<0.05).There was no significant influence on catalase(CAT)activity in hepatopancreases of juvenile black carp(P>0.05).Dietary YHY different level could improve the lipid deposition of hepatopancreases.In conclusion,based on the data analysis of SGR and PER,dietary YHY supplemental levels of 1.57%to 2.02%can significantly improve the growth performance,and at the same time,the YHY can improve the whole body and muscle amino acid composition,the quality of muscle and the hepatopancreases antioxidant enzyme activity of juvenile black carp.YHY does not adversely affect the hepatopancreases tissue morphology of juvenile black carp.