丙酸杆菌固态发酵物对蛋鸡生产性能及肠道菌群的影响OA

[Objective]The study aims to investigate the effects of Propionibacterium freudenreichii solid-state fermentation products used as a substitute for VB12 on the production performance,egg quality,immune indi-cators,and gut microbiota of laying hens.[Method]A total of 480 sixty-week-old Roman grey laying hens were selected for the experiment and randomly divided into 4 groups,with 4 replicates per group and 30 chickens per replicate.The control group was fed the basic diet and supplemented with 0.02 mg/kg cyanocobalamin(VB12).The experimental groups Ⅰ,Ⅱ,and Ⅲ were added with 0.07%,0.14%,and 0.21%solid-state fermentation products of Propionibacterium lactis on the basis of the basic diet,corresponding to 0.01,0.02,and 0.03 mg/kg of deoxyadenocobalamin,respectively.During the 35-day experimental period,the production performance,egg quality,immune indicators,and gut microbiota indicators of laying hens were measured separately.[Result]①Adding Propionibacterium freudenreichii solid-state fermentation products to laying hens'diet had no signifi-cant effect on the egg production rate,feed egg ratio,average egg weight,daily feed intake,and soft egg breakage rate(P>0.05).② Compared with the control group,the Haugh units in experimental groups Ⅰ and Ⅱ were significantly increased(P<0.05),while the egg shape index,eggshell strength,protein height,yolk color,egg-shell color,and eggshell thickness were not significantly affected(P>0.05).③ Compared with the control group,the levels of sIgA and IgM increased in groups Ⅱ and Ⅲ(P>0.05),while TNF-α and IFN-γ decreased(P>0.05).④ Adding solid-state fermentation products of Propionibacterium freudenreichii to laying hens'diet increased the OTUs,Ace index,and Chao 1 index of the cecum.At the genus level,it promoted an increase in the abundance of Bacteroidetes,Lactobacillus,and Rumen bacteria.[Conclusion]Comprehensively,under the conditions of this experiment,the solid-state fermentation product of Propionibacterium freudenreichii used as a substitute for VB12 did not show adverse effects on the production performance and egg quality of laying hens.When the addition level of the fermentation product was 0.14%,it had beneficial effects on the Haugh unit,im-mune indicators,and cecal microbiota.