迷迭香对蛋鸭生产性能、免疫指标和肠道菌群的影响OA

In order to investigate the effects of dietary supplementation with different levels of rosemary on the productive performance,immune indices,and intestinal microbiota of laying ducks,a total of 450 healthy 150-day-old Jinding ducks with similar body weights were randomly divided into 3 groups,with 3 replicates per group and 50 ducks per replicate.The control group was fed a basal diet,while the experimental groups RA150 and RA300(collectively referred to as the rosemary groups)were fed the basal diet supplemented with 150 mg/kg and 300 mg/kg rosemary,respectively,during a 53-day feeding trial.The results showed that dietary rosemary supplementation significantly improved the egg production rate(P<0.05),albumen height(P<0.05),and Haugh unit(P<0.01)of laying ducks,with the high-dose rosemary group(RA300)exhibiting the optimal production performance and egg quality indicators.Compared with the control group,serum IgA and IgM levels were significantly elevated in the RA150 group,while serum IgA and IgG levels were significantly increased in the RA300 group(P<0.05).Intestinal microbiota analysis results showed that at the phylum level,the colonic microflora of laying ducks was predominantly composed of Bacteroidota,Firmicutes,Fusobacteriota,and Proteobacteria,which jointly accounted for more than 90%of the total flora.At the genus level,Bacteroides and Fusobacterium were identified as the core dominant genera.Compared with the control group,the richness and evenness of the intestinal microbiota of the rosemary groups were significantly reduced(P<0.05),the relative abundance of potentially harmful taxa including Proteobacteria,Sutterella,Prevotellaceae Ga6A1 group and Butyricicoccus were significantly downregulated,while the relative abundance of Bacteroides showed an upward trend.The functional prediction analysis results indicated that the predictive abundances of pathways such as exosome synthesis and purine metabolism were increased in the rosemary groups,indicating functional remodeling of the microbiota towards anti-inflammatory and mucosal repair.In conclusion,dietary supplementation with rosemary can effectively improve the egg production performance and immune status,enhance egg quality,and exert potential anti-inflammatory and mucosal protective effects by remodeling the intestinal microbiota structure of laying ducks.