Effects Of Dietary Eucommia Ulmoides,Broad Bean Diets On Growth,Flesh Quality,and Collagen Gene Expression Of Grass Carp (Ctenopharyngodon Idella)

Exp.1 Effects of dietary Eucommia ulmoides on growth,flesh quality,andcollagengeneexpressionofgrasscarp(Ctenopharyngodon idella)The present study was conducted to investigate the effects of dietary Eucommia ulmoides(EU)on growth performance,flesh quality,collagen genes COL1A1 and COL1A2 expression of grass carp(Ctenopharyngodon idella).A total of 120 grass carp with an initial body weight of(150.0±0.4)g were randomly allocated 2 groups with 3 replicates per group and 20 fish per replicate.The fish were fed formula diet without(control)or with the supplementation of 2%Eucommia ulmoides(EU)for 8 weeks.The supplementation of 2%EU did not significantly affect the growth performance of grass carp when compared with the control(P>0.05),but increased the collagen content in muscle,skin and liver(P<0.05).Total essential amino acids(TEAA),total non-essential amino acids(TNEAA)and total amino acids(TAA)in muscle of grass carp fed EU diet were significantly higher than those of control group.Fish fed EU showed significantly lower flesh thawing loss and centrifugal loss(higher water holding capacity)(P<0.05),but muscle fiber density and muscle fiber diameter showed no difference between the two groups(P>0.05).Moreover,dietary EU significantly promoted the relative expression level of COL1A1 and COL1A2 mRNA in muscle,skin at the 4~thh week,the 8~thh week,and the expression in liver at the 8th week(P<0.05).In conclusion,dietary EU could improve the flesh quality of large size grass carp.Exp.2 Effects of dietary Eucommia ulmoides,broad bean diets on growth,flesh quality,and collagen gene expression of grass carp(Ctenopharyngodon idella)The present study was conducted to investigate the effects of dietary Eucommia ulmoides(EU)and broad bean on growth performance,flesh quality,collagen genes COL1A1 and COL1A2 expression of grass carp(Ctenopharyngodon idella).Three different diets,including formula diet(control),broad bean diet with a inclusion of 80%broad bean in formula diet without(BBD)or with the supplementation of 2%Eucommia ulmoides(BBD+EU)were designed to feed grass carp with an initial body weight of 172.2±0.5g for 12 weeks.BBD and BBD+EU did not significantly affect the growth performance,collagen level in muscle,skin and liver of grass carp,and total amino acid level in flesh when compared with the control(P>0.05),but significantly decreased muscle lipid content and intestinal fat ratio(IFR)(P<0.05).BBD and BBD+EU increased muscle fiber density and cooking loss in muscle,moisture content in BBD+EU and flesh thawing loss in BBD were also significantly increased(P<0.05).In collagen genes expression,BBD and BBD+EU significantly promoted the relative expression level of COL1A1 and COL1A2 mRNA in muscle,skin and liver at the 6~thh week and the 12~thh week(P<0.05),and the expression level of COL1A2 in muscle at the 12~thh week and in liver at the6~thh week were also significantly increased(P<0.05).In conclusion,dietary broad bean and broad bean+EU addition could improve the flesh quality of grass carp.