Effect Of Taurine On Hepatic Fat Metabolism In FLHS Laying Hens

Aim: Fatty liver hemorrhage syndrome(FLHS)is a common nutritional metabolic disease in laying hens,which is caused by fat metabolism disorder and excessive fat deposition in liver,resulting in fatty degeneration,hemorrhage and necrosis of liver cells,resulting in the decline of egg production rate and even death.Taurine is a kind of small molecular amino acid with a wide range of uses.It has a variety of functions,and also has a certain protective effect on the liver.Our previous research found that taurine can regulate liver fat metabolism,improve fat deposition and reduce fatty degeneration of liver cells in rats with fatty liver.The aim of this study was to investigate the effect of taurine on the expression of key factors of liver fat metabolism in FLHS laying hens by establishing FLHS model and adding taurine in diet,and to explore the regulatory mechanism of taurine on liver fat metabolism of FLHS layers,so as to provide theoretical basis for the application of taurine to prevent the occurrence of FLHS in laying hens.Methods: 180 of 300 days old Hailan brown layers were randomly divided into 5 groups: normal control group(C),taurine control group(T),FLHS model group(M),taurine prevention group I(MT1),taurine prevention group II(MT2).The laying hens of group C and group T were fed with soybean meal corn basal diet,and the laying hens of groups m,MT1 and MT2 were fed with high energy and low protein diet.The diets of MT1,MT2 and t groups were supplemented with 0.02% and 0.05% taurine respectively for 16 weeks.After the experiment,liver and serum were collected;paraffin sections were prepared and stained with he,frozen sections were stained with oil red O to observe the histological and pathological changes;the activities of alanine aminotransferase(ALT)and aspartate aminotransferase(AST),triglyceride(TG),total cholesterol(TC),free fatty acid(FFA)were detected Liver total RNA was extracted and the m RNA expression level of liver fat metabolism related factors was detected by q RTPCR.Results: the FLHS model was successfully established by feeding high energy and low protein diet.Liver histological observation showed that the liver cells of FLHS model had obvious steatosis,and the activities of serum ALT and AST were significantly increased compared with the control group(p<0.01);TC,TG,FFA in liver were significantly increased(p<0.01);liver CD36,SCD1,GPAT,AGPAT,PAP,DGAT,ADRP,SREBP1-C were significantly increased The m RNA expression levels of SREBP-1C,SREBP-2 and Ch REBP were significantly increased(p<0.01),ACC and Fas m RNA levels were significantly increased(p<0.05),the m RNA expression levels of L-FABP,CPT1,ATGL,HSL,MAGL and CGI58 genes were significantly decreased(p<0.01),and the m RNA expression levels of PPAR α gene were significantly decreased(p<0.05)Results: TC,TG,FFA in liver were significantly decreased(p<0.01),CD36,SCD1,GPAT,AGPAT,PAP,DGAT,ADRP,SREBP-1c,SREBP-2 and Ch REBP m RNA expression levels were significantly decreased(p<0.01),ACC and Fas gene m RNA expression levels were significantly decreased(p<0.05),L-FABP,CPT1,HSL,MAGL and CGI58 m RNA expression levels were significantly increased(p<0.01),PPAR α and ATGL base were significantly increased(p<0.01)The expression of m RNA increased significantly(p< 0.05)Conclusion: the FLHS model of laying hens was successfully established by feeding high energy and low protein diet.Taurine can inhibit the synthesis and decomposition of fatty acids,triglycerides and lipid droplets by regulating the expression of key enzymes and regulatory factors in the metabolism of fatty acids,triglycerides and lipid droplets in the liver,and promote their decomposition,thus reducing the liver fat deposition and preventing the occurrence of FLHS in laying hens.