Application Of Dicranostigma Leptopodum(Maxim.) Fedde In Animal Feed Additives

With the improvement of people’s living standard and the increasing concern about the safety of meat,eggs and milk products,it is increasingly urgent to find a safe and effective alternative to antibiotics as a green feed additive.In this study,Dicranostigma leptopodum(Maxim.)Fedde(DLF)was used as the main raw material to explore its application prospects as a green feed additive.Firstly,the method of control variables was used to set up gradient test,so as to optimize the extraction process of alkaloids in DLF.Subsequently,the optimal techniques obtained by experiments were used to compare the Isocorydine(ICD)content in different organs.Secondly,DLF was used as the main material in combination with other traditional Chinese medicine to design a variety of green additives,and their effects on the growth performance and health of chicken and carp were tested.The possible mechanism was explored from the changes of non-specific immune factors and anti-oxidation indexes,the effects on transcriptome levels of various tissues and intestinal flora.The results are as follows:1、The optimal conditions of ICD extraction were as follows: in 65% ethanol solution with p H=3,the ratio of material to liquid was 1:13,keeping the temperature constant at 70℃ for 4h.Under the optimum conditions,we found the flower bud> flower> root> whole plant> pod> seed through the comparison of the content of ICD in different organs.2、Effect of DLF on animal growth indicators: Group C1 can significantly reduce the feed-to-weight ratio of chickens and has a good growth promotion effect.The L2 group can promote the growth of carp,and the feed coefficient can be effectively reduced.3.DLF can significantly increase the content of animal non-specific immune factors or gene expression levels(1)Effect of DLF on non-specific immune indexes and antioxidant indexes of chickenDLF can increase the activity of ACP,AKP and LZM in serum.DLF can significantly increase the AKP activity in liver,spleen,kidney and bursa,but it can significantly reduce the LZM content in various tissues.Moreover,only the C3 group could significantly increase the activity of ACP and SOD in each tissue.In addition,in the liver and bursa,MDA content can be significantly reduced,but no significant change in the spleen and kidney.C2 group can significantly increase the GPT activity in liver,spleen,kidney and bursa.DLF can significantly reduce the expression of IFN-γ,IL-1β,TNF-ɑ,CYP1A1 and GST in the kidneys and bursa of chickens.In liver and spleen,DLF can significantly increase the expression levels of IFN-γ,TNF-ɑ,CYP1A1 and GST.(2)Effects of DLF on non-specific immune indexes and antioxidant indexes of carpThe L1 treatment group can significantly increase the ACP,AKP,LZM and SOD activities of carp liver,intestine and gills.L2 treatment group can significantly reduce MDA activity in liver,intestine and gills at 14 days.L1 treatment group can significantly reduce GPT activity in the liver at 14 days.Moreover,the GPT activity in the intestine and gills was significantly reduced in all three treatment groups.DLF can significantly increase the expression of IL-1β and GSTa in the intestine and gills at 14 days.The L2 group can significantly increase the expression level of IFN-γ and TNF-ɑ in intestinal tissue.Furthermore,DLF reduced the expression levels of IFN-γ,IL-1β,TNF-ɑ and GSTa in liver tissues at 14 days.DLF can significantly reduce the expression level of CYP1 A in liver tissues at 7 days,and significantly reduce its expression level in intestinal tissues at 14 days.4、DLF significantly affects the transcriptome of multiple tissues in chicken and carp(1)Analysis of DEGs revealed that it contains many genes related to growth,immunity andantioxidants.For example,IGFBP4,GDF7,EMP1,IGFBP1,LTBP1,BLB2,IL8L2,TLR2 A,TLR3,IL2 RA,IL1R2,IGLL1,STAT1,STAT2,GSTA3,CYP1A2,TGFB2,TGFBR2,LILRA3,IL34,CYP1A1,and so on.The GO enrichment analysis of DEGs found that multiple GO terms related to growth,immunity,and antioxidants were significantly enriched.For example,regulation of growth,regulation of insulin-like growth factor receptor signaling pathway,adaptive immune response,T cell-mediated immunity,antioxidant activity,response to oxidative stress,and so on.(2)KEGG enrichment analysis of DEGs found that multiple signaling pathways related to growth,immunity,and antioxidants were significantly enriched.For example,TGF-beta signaling pathway,m TOR signaling pathway,Toll-like receptor signaling pathway,NOD-like receptor signaling pathway,Intestinal immune network for Ig A production,Metabolism of xenobiotics by cytochrome P450 and so on.5、Effects of DLF on the intestinal flora of carp: DLF can significantly reduce the relative abundance of harmful bacteria and increase the relative abundance of beneficial bacteria,and can promote the diversity of bacteria.The above experimental results show that the rational use of DLF has a good effect on promoting growth,improving feed utilization rate and maintaining animal health.The basic mechanism is that DLF can increase the expression levels of growth and immune-related genes.These results provide reference data and theoretical basis for the development and application of green feed in the aquaculture industry.