Effects Of Probiotics On The Constipation And Immunity Of Sows In Late Gestation And Lactation

Sows are the core productivity of large-scale pig farms,and the late gestation and lactation periods are the critical stages that need to be optimized in large-scale production management of sows.From gestation to lactation,sows undergo dramatic changes in their physiology,metabolism,and immunity to meet the nutritional requirements.However,imbalanced nutrition during pregnancy and lactation can causes a range of health issues in sows,including constipation and chronic inflammation,which are extremely important in ensuring sow reproductive performance and the growth of offspring.In recent years,probiotics have been used in the swine industry to relieve constipation and inflammation,but the effects of probiotics vary considerably,the underlying probiotic mechanism is not well understood,and there is no systematic way to evaluate the efficacy of probiotics.Based on similar expected dates of confinement and backfat thickness,seventy-four sows(Large × Landrace;at 100 days gestation)were randomly allocated to the control(n = 38)and probiotic(n = 36)groups.The sows in the probiotic groups were reared with Bifidobacterium lactis Probio-M8 and Probio-M9(Lactobacillus rhamnosus)by the drinking water.This study evaluated the effect of supplementing sow drinking water with complex probiotics(comprised Probio-M8 and Probio-M9)on inflammatory,immune responses and reproductive performance in sows during late gestation and lactation.The second objective of this study was to further dissect the observed beneficial mechanisms via identifying probiotic-driven changes in the gut microbiota and blood metabolite biomarkers.The main conclusions were summarized as follows:(1)The effect of probiotic consumption on alleviating constipation in sows in late gestation(G100d,G106 d,G113d)and lactation(L6d,L13 d,L19d)was evaluated by the sow fecal score,and the sow fecal score is inversely related with the severity of constipation.Compared with the control group,probiotics administration significantly reduced the severity of constipation of sows in late gestation(G113d)and lactation(L6d,L13d).The mummification rate of piglets in the probiotic group was significantly lower than in the control group.The daily weight gain of piglets was significantly higher in the probiotic group compared with the control group.Additionally,the diarrhea days of piglets were non-significantly lower in the probiotic group compared with the control group.These data indicated that probiotic intake not only effectively alleviated constipation in sows at late gestation and lactation but improved the growth performance of piglets.(2)To reveal the immunomodulatory effect of supplementing compound probiotics in drinking water in sows during late gestation and lactation,the level of serum inflammatory cytokines was monitored.Compared with the control group,the serum levels of some of the monitored cytokines(IL-1β and IL-12p40)were significantly lower in the probiotic group at G113 d.The serum TNF-α level of sows decreased only in the probiotic group but not the control group at G113 d.The serum levels of IL-4,IL-10 and IFN-α in the probiotic group were significantly higher at L23 d.Compared with G100 d,the serum level of IL-4 in the probiotic group increased significantly at L23 d,while the serum level of IL-10 in the control group showed an opposite trend.Compared with G100 d,the serum levels of IFN-αof sows in both groups were significantly lower at G113 d.Compared with G113 d,the serum level of IFN-α in the probiotic group increased significantly at L23 d,while an opposite trend was observed in the control group.These results highlight the role of probiotics in reducing systemic inflammation in late gestation and lactation sows.(3)The fecal microbiota of the sows was analyzed at three time points(G100d,G113 d,and L23d)by metagenomic sequencing.Significant difference was observed in the alpha and beta diversity of the two groups of sows at G113 d.At the genus level,the abundance of Prevotellaceae exhibited significant intergroup differences between probiotic and control groups at both G113 d and L23 d.Compared with G100 d,the abundance of Prevotellaceae bacterium increased significantly in the probiotic group,and the abundance of campylobacter were significantly lower at G113 d.At the species level,the abundance of12 bacterial species was significantly higher in the probiotic group compared with the control group at G113 d,while an opposite trend was observed in 7 bacterial species.At 23 days of lactation(L23d),significantly more Butyricicoccus porcorum was detected in the probiotic group compared with the control group,while the abundances of Ruminococcaceae bacterium and Campylobacter lanienae showed an opposite trend.The detection result of sow fecal bacteriophage revealed that the alpha and beta diversity exhibited significant differences between probiotic and control groups at G113 d.At 113 days of gestation,significantly more Herelleviridae and Microviridae were detected in the probiotic group than the control group,while Siphoviridae,Podoviridae,and cr Ass-phage showed an opposite trend.These results together indicated that probiotic supplementation during late gestation and lactation significantly changed the gut bacteria and bacteriophage composition in sows.(4)The gut bioactive compounds of sows’ fecal samples were predicted using the Melonn Pan pipeline,and a total of 16 differentially abundant metabolites between the probiotic and control groups were predicted at G113 d and L23 d.To explore the enzyme repertoire for complex polysaccharide metabolism,CAZyme-encoding genes present in the sow fecal microbiome were identified.At 113 days of gestation,the cumulative abundance of genes in 78 CAZyme subfamilies was significantly higher in the probiotic group compared with the control group.These results of serum metabolomic analysis supported that a total of 9 differentially abundant metabolites(including the lutein,pyridoxamine,vitamin E,etc)in the probiotic recipients were significantly higher than the control sows at G113 d and L23 d.These results suggested that probiotic supplementation could modulate the predicted gut bioactive compounds,carbohydrate-active enzymes(CAZymes)and serum metabolites of sows in late gestation and lactation.The study found that the addition of complex probiotics(comprised Probio-M8 and Probio-M9)to drinking water during late gestation and lactation influenced the reproductive/growth performance of sows and piglets.In particular,the probiotic treatment significantly improved sow constipation and relieved systemic inflammation.The probiotic effects were likely achieved through orchestrated responses of the gut bacteriome,phageome,and bioactive metabolites,as well as colonic and systemic metabolism in the late gestation sows.This study provided scientific knowledge and practical information for both the academic community and the pig farming industry,expanding the scope of probiotic application in animal husbandry.