Application Of Ultra-Fine Grinding Yeast Cell Wall And Its Combination With Palygorskite In Feed Of Broilers

Yeast cell wall(YCW)and Palygorskite(Pal),which could improve immune function of animals,have been widely incorporated in animal feed.This study was conducted to investigate the bioactivities of ultra-fine grinding YCW and effects of dietary supplementation with ultra-fine grinding YCW plus Pal on the immune function,intestinal morphology,antioxidant ability and meat quality of broilers.The aim of this study was to supply a laboratory basis for the application of YCW and Pal in poultry.The study includes three trials and the results are presented as follows:The first trial was conducted to investigate the effects of ultra-fine grinding YCW on the immunity,intestinal morphology and antioxidant status of broilers.A total of 144 one-day-old Arbor Acres broiler chicks were allocated into 3 dietary treatments consisting of 6 replicates with 8 chicks per replicate(4 males and 4 females),and received a basal diet and basal diet supplemented with either 0.1%coarse or ultra-fine grinding YCW powder until 42 days of age,respectively.Treatments did not affect growth performance of broilers(P>0.05).Compared with the control group,total cholesterol content in serum(P = 0.032)and bursa weight(P = 0.019)were increased by the inclusion of YCW at 42 day.Ultra-fine rather than coarse grinding YCW powder reduced the crypt depth(P = 0.001)in jejunum,increased the ratio of villus height to crypt depth(P = 0.018)in jejunum,and ileal secretory immunoglobulin A(SIgA)(P = 0.040)and immunoglobulin G(P = 0.019)(IgG)content at 21 day.Additionally,birds fed diets containing ultra-fine grinding YCW showed increased ileal total superoxide dismutase(T-SOD)activity(P = 0.049)at 21 day whereas decreased malondialdehyde(MDA)accumulation(P = 0.021)at 42 day,respectively.The second trial was conducted to investigate the effects of dietary supplementation with ultra-fine grinding YCW,Pal,and their combination on the immunity,intestinal morphology and antioxidant status of broilers.A total of 256 one-day-old male Arbor Acres broiler chicks were randomly divided into a 2(YCW)×2(Pal)factorial arrangement with 8 replicates of 8 chicks each,receiving a basal diet,and the basal diet supplemented with 0.1%ultra-fine grinding YCW powder,1%Pal or their combination for 42 days,respectively.Compared with the control group,dietary supplementation with ultra-fine grinding YCW increased ileal IgG content(P = 0.001)at 21 day,and enhanced the colonization of Lactic acid bacteria(P = 0.006)in cecum and jejunal total superoxide dismutase activity(T-SOD)(P = 0.046)at 42 day.Dietary Pal inclusion increased ileal immunoglobulin M(IgM)content(P = 0.045)at 21 day.Additionally,the combination of ultra-fine grinding YCW and Pal increased average daily feed intake(ADFI)(P = 0.001)at early age,villus height(P = 0.008)and ratio of villus height to crypt depth(P = 0.017)in jejunum at 21 day,bursa weight(P = 0.007)at 42 day,whereas decreased ileal MDA accumulation(P = 0.022)at 42 day.The third trial was conducted to investigate the effects of dietary supplementation with ultra-fine grinding YCW,Pal,and their combination on the meat quality,muscular antioxidant ability,and mineral element content of broilers.The trial design and materials were the same as that in the second experiment.Compared with the control group,the inclusion of ultra-fine grinding YCW plus Pal increased the redness 24 h(P=0.032)and pH 24 h value(P = 0.006)whereas reduced MDA concentration(P = 0.001)of the thigh muscle at 42 day.Similarly,a combination of ultra-fine grinding YCW and Pal also decreased copper(Cu)(P = 0.019)and chromium(Cr)(P = 0.001)accumulations in the breast muscle.In conclusion,these results indicated that the ability to improve immune function,intestinal morphology and intestinal oxidative status of broilers was more pronounced in ultra-fine grinding YCW powder.Besides,dietary supplementation with ultra-fine grinding YCW and Pal in combination rather than separate inclusion exerted beneficial effects on immune function,intestinal morphology,antioxidant capacity and meat quality of broilers.