Effect Of Curcumin On Egg Quality And Liver Lipid Metabolism In Laying Hens

Starting from January 1,2020,the addition of antibiotics to feeds is completely banned in China.Natural and pollution-free farming is the main requirement in the modern livestock industry.Natural,harmless and effective feed additives will be searched and applied in the modern livestock industry.Curcumin is the main active ingredient of turmeric.A large number of studies reported that curcumin has antioxidant,anti-tumor,anti-inflammatory,anti-microbial,scavenging free radicals,and pharmacological effects and could protect the cardiovascular system and digestive system.In livestock industry,curcumin could improve performance,the quality of livestock and poultry products,but also improve the health status of livestock and enhance the economic benefits.In this experiment,curcumin was used to explore its effect on egg quality and liver lipid metabolism,and provide scientific guidance for the theoretical application of curcumin in laying hen production.1.Effects of curcumin on production performance,egg quality and plasma biochemical parameters of laying hensThe test used 600 55-week-old Su Qin No.1 laying hens,using a single factor design,and randomly divided into 5 groups according to the approximate principle of egg production rate,each group with 10 replicates(12 hens per replicate).The hens were fed with 0,100,200,400,or 800 mg curcumin//kg diet,respectively.The pre-feeding period is2 weeks,and the formal trial is 8 weeks.After the test,IBM SPSS Statistics 20 analysis software was used to analyze the production performance and egg quality.Finally,the control group(0)and the curcumin addition group(200)were selected and sampled.Compared with the control group,adding 200 mg/kg curcumin to the diet had no significant effect on the production performance of each group,but significantly improved the protein height,egg yolk color,haugh unit and eggshell thickness(P<0.05),and reduced the levels of GLU and CHOL in plasma(P<0.05).2.Effect of Curcumin on Egg Quality and Metabolism of Glycoprotein in oviduct magnum of laying hensThe albumen content of eggs were detected.Real-time fluorescence quantitative PCR was used to detect the expression of genes involved in glycoprotein metabolism in the oviduct magnum.Compared with the control group,addition of 200 mg/kg curcumin significantly reduced thin albumen weight and the ratio of thin albumen to content(P<0.05),and lowered the the expression of glycoprotein metabolism-related genes Prlr in the oviduct magnum(P<0.05).3.Effect of Curcumin on Liver Lipid Content and Liver Lipid Metabolism in laying hensHE and Oil Red staining were conducted to observe the liver pathological changes and fat deposition.The levels of hepatic TG,TC,SOD,MDA,CAT and GSH-Px were measured.Real-time fluorescence quantitative PCR to detect the expression of liver lipid metabolism-related genes.Western blot was used to detect the expression of liver lipid metabolism-related proteins.HE staining showed that 200 mg/kg curcumin addition significantly reduced the number of lipid droplets in the liver of laying hen.The result of Oil Red staining also indicated 200 mg/kg curcumin decreased the number of lipid droplets in the liver of the layer.Compared with the control group,the addition of 200 mg/kg curcumin significantly reduced the content of MDA,TC and TG in the liver(P<0.05),and down-regulated the expression of fatty acid synthesis genes Srebp-1 and Fasn(P<0.05).In addition,200 mg/kg curcumin significantly down-regulated the expression of hepatic FASN protein in hens(P<0.05).In summary:the addition of 200 mg/kg curcumin could significantly improve the protein height,egg yolk color,haugh unit and eggshell thickness of eggs,but down-regulate the expression of the glycoprotein synthesis gene Prlr in the oviduct magnum.The addition of 200 mg/kg curcumin markedly lowered the hepatic TC and TG content,down-regulated the expression of liver fatty acid synthesis related genes Srebp-1 and Fasn at the mRNA level,and down-regulated the expression of FASN at the protein level.