Effects Of Alfalfa Crude Polysaccharides On Production Performance And Egg Quality Of Laying Hens In High Temperature Environment In Summer

The study in this paper was conducted to analyze the effects of alfalfa crude polysaccharides on performance,egg quality,serum biochemical parameters,immune parameters endocrine hormones and antioxidant ability of laying hens under high temperature environment in summer.The purpose was to provide the experimental evidence for the application of alfalfa crude polysaccharide in laying hens.Five hundred and forty 156-day-old Hy-Line Brown laying hens were randomly allocated to 6 groups with 6 replicates per group and 15 hens per replicate.Hens in the control group were fed a basal diet,and those in experimental groups were fed basal diets supplemented with 250,500,1 000,2 000 and 4 000 mg/kg ACPS respectively.The experiment lasted for 6 weeks.The results were as follows: 1.Effects of alfalfa crude polysaccharides on performance and egg quality of laying hens under high temperature environment in summerCompared with the control group,1)diet supplemented with different levels of ACPS had no significant effects on average egg weight,average daily feed intake,unqualified egg rate and mortality rate(P>0.05).However,diet supplemented with 500,1 000 and 4 000 mg/kg ACPS significantly increased egg production(P<0.05),and diet supplemented with 500,1 000,2 000 and 4 000 mg/kg ACPS significantly decreased feed to egg ratio(P<0.05).2)Diet supplemented with different levels of ACPS had no significant effects on albumen height and Haugh unit(P>0.05).Diet supplemented with 250 mg/kg ACPS significantly increased yolk color at the end of week 4 and week 6(P<0.05).Diet supplemented with 500 mg/kg ACPS significantly decreased egg shape index at the end of week 6(P<0.05),meanwhile significantly increased yolk color at the end of week 1,week 4 and week 6(P<0.05).Diet supplemented with 1 000 mg/kg ACPS significantly improved eggshell color at the end of week 4 and week 6(P<0.05),significantly increased eggshell strength and thickness at the end of week 1,week 2 and week 4(P<0.05),significantly decreased egg shape index at the end of week 1 and week 6(P<0.05),and significantly increased yolk color at the end of week 1,week 2,week 4 and week 6(P<0.05).Diet supplemented with 2 000 mg/kg ACPS significantly increased eggshell thickness at the end of week 1 and week 4(P<0.05),significantly decreased egg shape index at the end of week 6(P<0.05),and significantly increased yolk color at the end of week 1,week 4 and week 6(P<0.05).Diet supplemented with 4 000 mg/kg ACPS significantly improved eggshell color and eggshell strength at the end of week 4(P<0.05),significantly increased eggshell thickness at the end of week 1 and week 4(P<0.05),significantly decreased egg shape index at week 6(P<0.05),and significantly increased yolk color at the end of week 1,week 4 and week 6(P<0.05).2.Effects of alfalfa crude polysaccharides on serum biochemical parameters and immune globulins of laying hens under high temperature environment in summerCompared with the control group,1)diet supplemented with different levels of ACPS had no significant effects on serum concentrations of GLU,Ca,CHOL,TG,HDL-C,TP,ALB,UREA and ALT activity(P>0.05).Diet supplemented with 500 mg/kg ACPS significantly decreased serum AST activity at the end of week 2(P<0.05).Diet supplemented with 1 000 mg/kg ACPS significantly decreased serum ALP activity at the end of week 2(P<0.05),significantly decreased CK activity at the end of week 4(P<0.05),and significantly decreased LDH and CK activity at the end of week 6(P<0.05).Diet supplemented with 2 000 mg/kg ACPS significantly decreased serum LDH and CK activity at the end of week 6(P<0.05).Diet supplemented with 4 000 mg/kg ACPS significantly decreased serum P concentration and ALP activity(P<0.05)and significantly increased LDH activity at the end of week 4(P<0.05),and significant decreased serum LDL-C concentration at the end of week 6(P<0.05).2)Diet supplemented with 1 000 mg/kg ACPS significantly increased levels of serum IgA and IgM at the end of week 6(P<0.05).Diet supplemented with 2 000 mg/kg ACPS significantly increased levels of serum IgA and IgM at the end of week 2(P<0.05),and significantly increased levels of serum IgA,IgG and IgM at the end of week 6(P<0.05).3.Effects of alfalfa crude polysaccharides on serum hormones and antioxidant ability of laying hens under high temperature environment in summerCompared with the control group,1)diet supplemented with different levels of ACPS had no significant effects on serum P4 concentration(P>0.05).Diet supplemented with 250 and 500 mg/kg ACPS significantly increased serum E2 concentration at the end of week 6(P<0.05).Diet supplemented with 1 000 mg/kg APS significantly increased serum FSH concentration at the end of week 2 and serum LH concentration at the end of week 6(P<0.05).Diet supplemented with 2 000 mg/kg APS significantly increased serum concentrations of COR and FSH at the end of week 2(P<0.05).Diet supplemented with 4 000 mg/kg APS significantly increased serum COR concentration at the end of 2 and serum LH concentration at the end of week 6(P<0.05).2)Diet supplemented with different levels of APS had no significant effects on serum GSH-Px and SOD activity(P>0.05).Diet supplemented with 500 mg/kg APS significantly increased serum T-AOC level at the end of week 2(P<0.05).Diet supplemented with 1 000 mg/kg APS significantly increased serum T-AOC level at the end of week 2 and 6(P<0.05),and significantly decreased MDA concentration at the end of week 2(P<0.05).Diet supplemented with 2 000 mg/kg APS significantly increased serum T-AOC level at the end of week 6(P<0.05).Diet supplemented with 4 000 mg/kg APS significantly increased serum T-AOC level and decreased MDA concentration at the end of week 2(P<0.05).The study indicates that moderate ACPS supplementation can effectively alleviate heat stress of laying hens,improve its production performance,egg quality,serum immune globulin levels,and antioxidant ability,promote secretion of serum hormones(COR,E2,FSH and LH),decrease serum LDH,AST and CK activity,and increase activity of ALP under high temperature environment in summer.The optimum supplemented level is 1 000 mg/kg.