Effects Of Selenium And Butyric Acid Derivative On Production Performance And Egg Quality Of Aged Laying Hens

The main common problems facing the poultry industry in older laying hens are the decrease in the production and both internal and external egg quality,which leads to great economic losses.This is probably due to the occurrence of metabolic disease,these metabolic disease occurrences were associated with the decreasing of antioxidant states and immune defense system,Butyrate acid,a kind of short chain fatty acids,is usually added into feed in the form of inorganic butyrate or butyrate glycerides,with the effects of improvement of intestinal health,immunity and liver fatty acid metabolism in animals,Selenium is an essential nutrient for animals,with potential functions in antioxidant defense,immunity,an antitumorigenesis,Therefore,the objective of this study is to investigate the effects of butyrate,butyrate glycerides and Selisseo combination on the performance,egg quality and health status of the aged laying hens and the relative mechanisms.Select 900 45 week-old Hailan brown laying hens with good health and similar weight,and randomly divide them into 5 groups with 10 replicates in each group,18 laying hens in each replicates,and the 5 groups of diets are added respectively: Control,basal diet supplemented with 0.3 mg Se/kg as sodium selenite;CB,basal diet supplemented with 0.3 mg Se/kg as sodium selenite and 240 mg/kg butyric acid as coated butyrate;BG,basal diet supplemented with 0.3 mg Se/kg as sodium selenite and 240mg/kg butyric acid as butyric glycerides;CB+Se O,basal diet supplemented with 0.3 mg Se/kg as hydroxy-Selenomethionine and 240 mg/kg butyric acid as coated butyrate;BG+Se O,basal diet supplemented with 0.3 mg Se/kg as hydroxy-Selenomethionine and240 mg/kg butyric acid as butyric glycerides.After 20 weeks of trial feeding,the number and weight of eggs were recorded every day,and the feed intake was recorded every week.It is used to calculate the average daily feed intake,egg production rate,total egg weight and feed conversion rate.At the 5th,10 th,16th and 20 th weeks of the experiment,all eggs will be collected for egg quality determination.The samples were slaughtered on the last day of the experiment,and serum biochemical,inflammatory factors,antioxidant indicators,liver,uterus,isthmus of fallopian tube liver related gene m RNA expression,TC,TG content were measured.The main results are as follows:1.Compared to the control,dietary supplementation of CB,BG,CB+Se O,BG+Se O increased(P < 0.05)total egg weight and egg-laying ratebut reduced(P < 0.05)feed/egg ratio,dietary supplementation of BG+Se O displayed better effects on these Performance parameters than all the other treatment.However,all the treatment did not affect the mortality during the trial.2.Compared to the control,dietary supplementation of CB,BG,CB+Se O,BG+Se O decreased egg yolk color and eggshell thickness(P < 0.05)at weeks 5 and 10,but increased egg yolk color(P < 0.05)and eggshell thickness at week 20;the average egg weight of eggs was increased in all time periods,dietarysupplementation of CB+Se O and BG+Se O increased(P < 0.05)selenium concentration.3.Compared to the control,dietary supplementation of CB,BG,CB+Se O and BG+Se O decreased(P < 0.05)ALT、MDA and IL-6 concentration,but decreased(P < 0.05)TP、Ig M、Ig G(P < 0.05)concentration and GPX activity,However,the CB+Se O and BG+Se O groups also decreased TNF-α(P < 0.05),BG+Se O group also increased the content of IL-10 and the activity of T-AOC and SOD(P < 0.05).4.Compared with the control,the CB,BG,CB+Se O,and BG+Se O groups decreased the content of MDA in the liver tissue and increased the activity of GPX(P < 0.05),In addition,the diet supplemented with BG+Se O also decreased the content of TC and TG in liver tissue(P < 0.05).Compared with the control group,the CB+Se O group significantly decreased the expression of ACC1 m RNA in the liver(P < 0.05),while the BG+Se O group significantly increased the expression of IL-10 and CPT1 Am RNA,and significantly decreased expression of TNF-α(P < 0.05)IL-6,FAS,and ACC1 m RNA.In conclusion,the simultaneous addition of Se O,butyrate,and glyceryl butyrate can improve the production performance,redox status,immunity,and liver lipid metabolism of aged laying hens,and the simultaneous addition of Se O and glyceryl butyrate has a better effect.