The Effect Of Dietary Yucca Schidigera Extract Supplementation On Productive Performance And Gut Health In Laying Hens With Clostridium Perfringens And Coccidia Challenge

As a green feed additive,Yucca schidigera extract(YSE)can reduce the emission of toxic gas in animal production,and improve intestinal health.Clostridium perfringens(C.perfringens)is an opportunistic pathogen,which can infect gut in humans and animals,induce inflammation,and affect growth and health,and then cause economic losses in poultry breeding.Via setting up a model of laying hens with C.perfringens and coccidia challenge,this study aimed to investigate whether dietary YSE supplementation could attenuate the negative effects of C.perfringens and coccidia challenge on productive performance and intestinal health in laying hens.A 2× 2 factorial design,including the main effects of C.perfringens and coccidia challenge,and dietary YSE supplementation,was used in this trial.On d 1,a total of48 Lohmann gray hens(35 wk of age)were randomly divided into 2 groups(n = 24)fed with the basal diet or the YSE-supplemented diet.At each day of d 36-45,half of the hens in each group were orally administrated C.perfringens type A and coccidiosis vaccine,and the other hens were orally infused the same dose of sterile phosphate solution.The whole trial period was 45 d.The results were showed as follows.(1)Before the challenge(d 1-35),dietary YSE supplementation had no significant effect on productive performance and egg quality in laying hens(P > 0.05).After challenge(d 36-45),C.perfringens and coccidia challenge significantly reduced ADFI,laying rate and egg weight(P < 0.05),significantly increased FCR(P < 0.05),and significantly affected egg quality(including albumen weight,yolk weight,yolk color,shell thickness,shell weight and shell color)(P < 0.05).Supplementing YSE in diet significantly increased egg weight and albumen weight(P < 0.05),and tended to increase albumen height(P = 0.055).In the laying hens infected by C.perfringens and coccidia,YSE administration significantly alleviated the decrease of egg weight,albumen height,albumen weight and yolk weight(P < 0.05).(2)The morphology was intact,and had no pathological changes in the jejunum of non-challenge laying hens.In the jejunum of laying hens feeding the basal diet and challenge of C.perfringens and coccidia,villi were atrophic,epithelial structure was damaged,intestinal glands were atrophic,and mucous and muscular layers had the extensive infiltration of neutrophils.In the jejunum of laying hens feeding the YSE-supplemented diet and challenge of C.perfringens and coccidia,epithelial structure was normal,some intestinal glands were atrophic,and mucous and muscular layers had the infiltration of some neutrophils.C.perfringens and coccidia challenge significantly increased the jejunal lesion score and crypt depth(P < 0.05),significantly decreased the jejunal villus height and crypt depth ratio and the trypsin,amylase and lipase activities of jejunal digesta(P < 0.05),and significantly downregulated the relative mRNA expression of ZO-1,ZO-2,CLDN-1 and OCLN of jejunum(P < 0.05)in laying hens.Dietary YSE supplementation significantly reduced the jejunal lesion score and crypt depth(P < 0.05),significantly increased the jejunal villus height and crypt depth ratio and the trypsin and lipase activities in jejunal digesta(P < 0.05),and significantly upregulated the relative mRNA expression of CLDN-1 of jejunum(P < 0.05)in laying hens.And in the laying hens infected with C.perfringens and coccidia,supplementing YSE in diet alleviated the increase of jejunal crypt depth and lesion score,the downregulation of mRNA relative expression of CLDN-1 in the jejunum,and the decrease of trypsin and lipase activities in the jejunal digesta(P < 0.05).(3)C.perfringens and coccidia challenge significantly increased the number of apoptotic cells in the jejunum of laying hens(P < 0.05).Dietary YSE supplementation significantly decreased the number of apoptotic cells in the jejunum of laying hens(P< 0.05).And in the jejunum of laying hens infected with C.perfringens and coccidia,supplementing YSE in diet significantly alleviated the increase of apoptotic cell number(P < 0.05).(4)C.perfringens and coccidia challenge significantly increased serum MDA level and jejunal MPO activity(P < 0.05),tended to increase the jejunal MDA level(P = 0.052),significantly decreased the jejunal T-AOC(P < 0.05),and significantly downregulated the relative mRNA expression of NQO1 and Nrf2 of jejunum(P <0.05)in laying hens.Dietary YSE supplementation significantly increased serum and jejunal T-AOC(P < 0.05),tended to reduce serum(P = 0.084)and jejunum(P =0.078)MDA levels,and significantly upregulated the relative mRNA expression of NQO1 and Nrf2 of jejunum in laying hens(P < 0.05).And in the laying hens infected with C.perfringens and coccidia,supplementing YSE in diet significantly alleviated the negative effects of challenge on serum T-AOC and MDA levels,and jejunal T-AOC,MDA levels,MPO activity,and relative mRNA expression of NQO1 and Nrf2(P < 0.05).(5)Both dietary YSE supplementation and C.perfringens and coccidia challenge did not caused morphological and pathological changes of ovary,and did not significantly affect the apoptosis levels of ovary,the T-AOC,MDA level or MPO activity of ovary,uterus and magnum tubae uterinae in laying hens(P > 0.05).In conclusion,C.perfringens and coccidia challenge damaged jejunal health,and led to the decrease of productive performance and egg quality in laying hens.Dietary YSE supplementation could,to some extent,improve the productive performance and egg quality of C.perfringens and coccidia-infected hens,which could be derived from YSE alleviating jejunal damage and dysfunction by enhancing antioxidant capacity.