Effects Of Mulberry Leaves And Their Compounds On The Growth,antioxidant Responses And Immunity Of Gift Oreochromisniloticus

In this paper,the effects of different levels of mulberry leaf(Morus alba)and its compound on growth performance,antioxidant performance,immunity and serum biochemistry of GIFT(Genetic Improvement of Farmed Tilapia,GIFT Oreochromis niloticus)were studied.630 healthy G.tilapia with an initial body weight of 13.45±0.05 g were randomly divided into 7 groups(D0,M1,M2,M3,MC1,MC2 and MC3),3 replicates in each group,30 replicates per replicate.An 60-day growth test was carried out in an indoor recirculating aquaculture system(volume 250 L).The base diet was used as the control group D0,and the other test groups were supplemented with 1%,4%,and 8%(M1-M3)of mulberry leaf powder and 1%,4%,and 8%(MC1-MC3)by the mulberry leaf compound powder which consisting of mulberry leaves,echinacea,epimedium,isatis tinctoria and radix astragali.To study the optimum addition amount of mulberry leaves and their compound in the basic diet of G.tilapia,and provide a theoretical basis for the scientific and rational preparation of mulberry leaves and their compounds in freshwater aquaculture.The main research contents and results are as follows:1.Effects of mulberry leaves and its compounds on growth performance and body composition of G.tilapia Compared with the control group,there were no significant differences in the IBW(Initial body weight),FBW(Final body weight),WGR(Weight gain rate),SGR(Specific growth rate)and SR(Survival rate)of different levels of mulberry leaves and their compounds in the diet(P>0.05).The addition of 1% mulberry compound had a significant increase in the protein efficiency of G.tilapia(P<0.05),but significantly reduced the FCR(Feed coefficient ratio)(P<0.05).Added 4% mulberry leaves and 1%,4%,8% mulberry compound significantly reduced the FI(Feed intake)of tilapia(P<0.05).The addition of 8% mulberry leaf compound had a significant effect on the CF(Condition factor)(P<0.05).There were no significant differences in the moisture,CP(Crude protein)and CA(Crude ash)content of the whole fish with different levels of mulberry and its compounds in the feed(P>0.05).After adding 8% mulberry leaves and 1%,4%,8% mulberry compounds,the CF(Crude fat)content of whole fish increased significantly(P<0.05).The addition of different levels of mulberry leaves and its compounds had no significant effect on muscle moisture,CP,CF and CA(P>0.05).2.Effects of mulberry leaves and its compound on antioxidant activity of G.tilapia Compared with the control group,the levels of ACP(Acid Phosphatase)and AKP(Alkaline Phosphatase)in the serum of G.tilapia were not significantly different when the feed was added with different levels of mulberry and mulberry leaves(P>0.05).The activity level of LZM(Lysozyme)in serum of 4% and 8% mulberry compound treatment group was significantly higher than that of the control group(P<0.05).The activity levels of ACP,AKP and LZM in the liver of G.tilapia treated with 1%,4%and 8% mulberry compound treatment groups were significantly up-regulated compared with the control group(P<0.05).Compared with the control group,the addition of different levels of mulberry leaves and its compounds had no significant effect on the activity of T-AOC(Total Antioxidant Capacity),CAT(Catalase)and MDA(Malondialdehyde)in the serum of G.tilapia(P>0.05).The addition of 8% mulberry compounds treatment group significantly enhanced the activity of SOD(Superoxide Dismutase)in the serum of G.tilapia(P<0.05).According to the order of D0,M1,M2,M3,MC1,MC2 and MC3,the activity levels of T-AOC,SOD and CAT in the liver of G.tilapia showed a significant upward trend(P<0.05),and the upward trend of the 8% mulberry compound treatment group was the most significant.3.Effect of mulberry leaves and its compounds on serum biochemical indexes of G.tilapia Compared with the control group,the effects of different levels of mulberry leaf and its compounds on ALT(Alanine Aminotransferase),LDL-C(Low Density Lipoprotein Cholesterol)),HDL-C(High-density Lipoprotein Cholesterol),TG(Triglyceride),GLB(Globulin),ALB(Albumin)and TP(Total Protein)were not significant(P>0.05).Compared with the control group,AST/ALT(Aspartate Transaminase/Alanine Aminotransferase)with 4% mulberry compound was significantly increased(P<0.05).Compared with the control group,8% of mulberry leaf in the feed had a significant increase in AST content(P<0.05).Compared with the control group,the effects of different levels of mulberry leaf and its compounds on the TC(Total Cholesterol)were not significant(P>0.05).4.Effect of mulberry leaves and its compounds on the relative expression of immune factors in G.tilapia Compared with the control group,the addition of 1% mulberry leaf compound test group MC1,4% mulberry leaf compound test group MC2,and 8% mulberry leaf compound test group MC3 in the feed showed a significant increase trend in the relative expression of each immune factor.Compared with the control group,the expression of IL-1(Interleukin-1)and IL-2(Interleukin-2)was significantly up-regulated(P<0.05).The expression of IL-10(Interleukin-10)was not significantly different in the 1% mulberry leaf compound test group(P>0.05),but significantly increased in the 4% and 8% mulberry compound test group(P<0.05).The expression of IFNγ(Interferon-γ)was significantly up-regulated in the 8% mulberry compound test group(P<0.05),and the difference was not significant in the other groups(P>0.05).TLR-2(Toll-like receptors)was significantly up-regulated in the 1%,4% and 8% mulberry compound test group(P<0.05),and the difference in expression in the 8% mulberry compound test group was the most obvious.In summary,the addition of mulberry leaves and its compounds to the feed has little effect on the growth of tilapia.Adding 4% and 8% of mulberry compound to the feed can increase the activity of ACP,AKP and LZM in the liver,while the 8% mulberry compound treatment group shows certain advantages in total antioxidant capacity and expression of immune factors,but significantly reduced the feeding rate.Therefore,in the promotion and application,in order to meet the protein demand while providing protection against oxidation and immunity,it is recommended to add 1%-4% mulberry leaf compound to the basic feed of tilapia.