Effects Of Dietary Fiber On Production Performance,eggshell Quality,immunoglobulin,intestinal Structure And Cecal Microorganism Of Laying Hens

In this study,the effects of dietary fiber on the production performance,eggshell quality,immunoglobulin,intestinal structure and cecal microorganism of brown laying hens were investigated.384 healthy hailan brown commercial reserve layer hens(120 days of age)were randomly divided into 4 groups,with 6 replicates in each group and 16 chickens in each repetition.The control group was fed with the basal diet,and the basal diet of experimental group T1,T2 and T3 were added with 0.8%,1%and 1.2%dietary fiber respectively.All layer hens were raised according to the standard procedures.Meanwhile,production performance,eggshell quality,immunoglobulin,intestinal structure and cecal microorganism of layer hens were analyzed,and the following results were obtained:1.Effect of dietary fiber on production performance of laying hens.The egg-laying rates of laying hens(180 days of age)were respectively 89.9%,89.2%,87.8%and 87.3%in experimental group T3,T2,T1 and control group.Meanwhile,each hen in corresponding experimental group produced averagely 35.38,34.57,33.93,and 33.75 eggs.This showed that dietary fiber in diet slightly improved the egg production rate of laying hens,but without significant difference.The mean weight of laying hens(180 days of age)between the 4 groups have no significant difference,in which group T3 have the heaviest one(1799.33g),and control group have the lowest one(1724.67.33g).The mean egg weight in experimental group T3,T2,T1 and control group were respectively 56.8,55.1,54.3,and 53.6g.The mean egg weight of experimental groups were significantly higher than that of control group,but have no significant difference between the 3 experimental groups.The feed/egg rates of group T3 and T2 were lower than that of control group(P<0.05)and group T1(P>0.05),but there is no significant difference between control group and group T12.The effect of dietary fiber on the quality of eggshellGroup T3 and control group have the highest(2.91kg/cm~2)and lowest(2.79kg/cm~2)intensity of eggshell respectively,and the intensity of eggshell of the other group have no significant difference.The shell thickness,shape index and eggshell color of eggs between the 4 groups have no significant difference.Group T3 have the thickest shell thickness(0.36mm),highest shape index(1.28)and eggshell color(49.21).Control group have the thinnest shell thickness(0.32mm),lowest shape index(1.26)and eggshell color(48.65).3.The effect of dietary fiber on the immunoglobulin in serumThe contents of Ig A,Ig G and Ig M between the 4 groups were significantly different.Group T3 have the highest contents of Ig A(628.31μg/m L),Ig G(1778.75μg/m L)and Ig M(675.23μg/m L).Control group have the lowest contents of Ig A(603.31μg/m L),Ig G(1716.57μg/m L)and Ig M(637.43μg/m L).4.The effect of dietary fiber on the intestinal structureCompared with the control group,the height and V/C values of duodenal villi in experimental groups tended to increase,and the intestinal wall thickness of experimental groups tended to decrease.The villi height of experimental group T1,T2and T3 increased 15.42%,18.41%and 20.39%,respectively,compared with that of the control group(P<0.05).The V/C value of experimental group T1,T2 and T3increased 3.06%,3.82%,and 5.35%,respectively,compared with that of the control group(P>0.05).the intestinal wall thickness of experimental group T1,T2 and T3increased 18.86%,21.93%and 25.00%,respectively,compared with that of the control group(P<0.05).5.The effect of dietary fiber on the cecal microorganismThe 16s r DNA sequencing analysis of cecal microorganisms showed that the180-day-old layer hens of experimental group T3 had the largest number of intestinal flora with large richness.And the flora analysis showed that the main dominant flora affecting the intestinal tract and digestion and absorption of layer hens in experimental group 3 were vibrio vulgaris,phylum verruca,δ-proteobacteria,vibrio desulphurization,bacteria that can degrade mucin,and fungophile fungi,etc.Conclusion:Adding adequate dietary fiber to the diet improved the production performance,immunoglobulin and eggshell quality of hailan brown laying hens,improved the intestinal morphology and structure,and promoted the proliferation of cecal microorganisms.