Diet is a major modulator of animal resilience and its three pillars:host's immune response,gut microbiota,and intestinal barrier.In the present study,we endeavour to delineate a challenging con-dition aimed to de...Diet is a major modulator of animal resilience and its three pillars:host's immune response,gut microbiota,and intestinal barrier.In the present study,we endeavour to delineate a challenging con-dition aimed to degrade these pillars and elucidate its impact on broiler performance and nutrient di-gestibility.To attain this objective,we opted to use guar gum(GG)as a source of galactomannan.A series of three in vivo experiments were conducted employing conventional or semi-purified diets,supple-mented with or without GG during the grower phase(14-28 d).Our findings demonstrate a substantial decline in animal performance metrics such as body weight(reduced by 29%,P<0.001),feed intake(decreased by 12%,P<0.001),and feed conversion ratio(up to 58%increase,P<0.001)in the presence of GG at 2%.The supplementation of a semi-purified diet with incremental doses of GG resulted in a linear reduction(P<0.001)in the apparent total tract digestibility of dry matter and apparent metabolisable energy.Additionally,a marked reduction in ileal endogenous losses,as well as apparent and standardised digestibility of all amino acids with varying proportions(P<0.05),was observed.These alterations were accompanied by disrupted gut integrity assessed by fluorescein isothiocyanate-dextran(FITC-d)(P<0.001)as well as an inflammatory status characterised by elevated levels of acute-phase proteins,namely orosomucoid and serum amyloid A in the sera(P=0.03),and increased mRNA expression levels of IL-1,IL-6,IL-8,Inos,and K203 genes in the ileum,along with a decrease in IgA levels in the gut lumen(P<0.05).Microbial ecology and activity were characterised by reduced diversity and richness(Shannon index,P=0.005)in the presence of GG.Consequently,our results revealed diminished levels of short-chain fatty acids(P=0.01)and their producer genera,such as Clostridium_XIVa and Blautia,in the gut caeca,coupled with excessive accumulation of lactate(17-fold increase,P<0.01)in the presence of GG at 2%.In addition to providing a more comprehensive characterisation of the GG supplementation as a leaky gut model,our results substantiate a thorough understanding of the intricate adjustments and interplay between the intestinal barrier,immune response,and microbiota.Furthermore,they underscore the significance of feed components in modulating these dynamics.展开更多
文摘Diet is a major modulator of animal resilience and its three pillars:host's immune response,gut microbiota,and intestinal barrier.In the present study,we endeavour to delineate a challenging con-dition aimed to degrade these pillars and elucidate its impact on broiler performance and nutrient di-gestibility.To attain this objective,we opted to use guar gum(GG)as a source of galactomannan.A series of three in vivo experiments were conducted employing conventional or semi-purified diets,supple-mented with or without GG during the grower phase(14-28 d).Our findings demonstrate a substantial decline in animal performance metrics such as body weight(reduced by 29%,P<0.001),feed intake(decreased by 12%,P<0.001),and feed conversion ratio(up to 58%increase,P<0.001)in the presence of GG at 2%.The supplementation of a semi-purified diet with incremental doses of GG resulted in a linear reduction(P<0.001)in the apparent total tract digestibility of dry matter and apparent metabolisable energy.Additionally,a marked reduction in ileal endogenous losses,as well as apparent and standardised digestibility of all amino acids with varying proportions(P<0.05),was observed.These alterations were accompanied by disrupted gut integrity assessed by fluorescein isothiocyanate-dextran(FITC-d)(P<0.001)as well as an inflammatory status characterised by elevated levels of acute-phase proteins,namely orosomucoid and serum amyloid A in the sera(P=0.03),and increased mRNA expression levels of IL-1,IL-6,IL-8,Inos,and K203 genes in the ileum,along with a decrease in IgA levels in the gut lumen(P<0.05).Microbial ecology and activity were characterised by reduced diversity and richness(Shannon index,P=0.005)in the presence of GG.Consequently,our results revealed diminished levels of short-chain fatty acids(P=0.01)and their producer genera,such as Clostridium_XIVa and Blautia,in the gut caeca,coupled with excessive accumulation of lactate(17-fold increase,P<0.01)in the presence of GG at 2%.In addition to providing a more comprehensive characterisation of the GG supplementation as a leaky gut model,our results substantiate a thorough understanding of the intricate adjustments and interplay between the intestinal barrier,immune response,and microbiota.Furthermore,they underscore the significance of feed components in modulating these dynamics.