Background Subacute rumen acidosis(SARA)is a common metabolic disorder in ruminants that disrupts the rumen microbiome and animal health,but diagnosis is challenging due to subtle symptoms and invasive testing require...Background Subacute rumen acidosis(SARA)is a common metabolic disorder in ruminants that disrupts the rumen microbiome and animal health,but diagnosis is challenging due to subtle symptoms and invasive testing require-ments.This study explores the potential of the buccal(oral)microbiome as a diagnostic indicator for SARA,hypoth-esizing an interaction with the rumen microbiome.Results The study involved 47 dairy goats,including 11 on a control diet and 36 on high-concentrate diets with increasing rumen-degradable starch.Animals were grouped based on dietary exposure and ruminal pH:Control,Low-RDS Tolerance/SARA(LRDST/LRDSS),and High-RDS Tolerance/SARA(HRDST/HRDSS).Transcriptomics of rumen epithelium showed heightened inflammatory pathway gene expression in SARA-susceptible goats compared to controls and tolerant groups.Alpha diversity of ruminal bacteria showed lower Shannon diversity in HRDSS goats compared to HRDST whereas buccal bacteria displayed significantly lower Chao1 diversity in LRDSS goats compared to HRDST.Beta diversity analyses revealed distinct patterns between SARA-affected goats and healthy controls in both ruminal and buccal microbiomes.Prevotellaceae_UCG-003 emerged as a candidate biomarker,with reduced abundance in SARA-susceptible goats in both rumen and buccal samples.Machine learning classifiers achieved high accuracy in distinguishing SARA-susceptible goats using this genus(rumen AUC=0.807;buccal AUC=0.779).Source tracking analysis illustrated diminished cross-population of bacteria from the buccal to rumen(2.86%to 0.25%)and vice versa(8.59%to 1.17%),signifying compromised microbial interchange in SARA-affected goats.A microbiota transplant experiment verified SARA microbiota’s ability to induce pH decline,escalate inflammation-related gene expression(MAPK10,IL17B,FOSB,SPP1),disrupt microbial transfer,and reduce Prevotellaceae_UCG-003 in recipients.Conclusion Our findings highlight SARA’s dual impact on ruminal and buccal microbiota,exacerbating epithelial inflammation gene expression.Shifts in the buccal microbiome,specifically reductions in Prevotellaceae_UCG-003,mirror ruminal changes and can be influenced by inter-compartmental bacterial transmission,thereby offering a non-invasive diagnostic approach for SARA.展开更多
基金supported by the National Key Research and Development Program for International Science and Technology Innovation Cooperation between Governments(2023YFE0111800)the Shaanxi Province’s San Qin Talent Attraction Program for Regional Youth Talents.
文摘Background Subacute rumen acidosis(SARA)is a common metabolic disorder in ruminants that disrupts the rumen microbiome and animal health,but diagnosis is challenging due to subtle symptoms and invasive testing require-ments.This study explores the potential of the buccal(oral)microbiome as a diagnostic indicator for SARA,hypoth-esizing an interaction with the rumen microbiome.Results The study involved 47 dairy goats,including 11 on a control diet and 36 on high-concentrate diets with increasing rumen-degradable starch.Animals were grouped based on dietary exposure and ruminal pH:Control,Low-RDS Tolerance/SARA(LRDST/LRDSS),and High-RDS Tolerance/SARA(HRDST/HRDSS).Transcriptomics of rumen epithelium showed heightened inflammatory pathway gene expression in SARA-susceptible goats compared to controls and tolerant groups.Alpha diversity of ruminal bacteria showed lower Shannon diversity in HRDSS goats compared to HRDST whereas buccal bacteria displayed significantly lower Chao1 diversity in LRDSS goats compared to HRDST.Beta diversity analyses revealed distinct patterns between SARA-affected goats and healthy controls in both ruminal and buccal microbiomes.Prevotellaceae_UCG-003 emerged as a candidate biomarker,with reduced abundance in SARA-susceptible goats in both rumen and buccal samples.Machine learning classifiers achieved high accuracy in distinguishing SARA-susceptible goats using this genus(rumen AUC=0.807;buccal AUC=0.779).Source tracking analysis illustrated diminished cross-population of bacteria from the buccal to rumen(2.86%to 0.25%)and vice versa(8.59%to 1.17%),signifying compromised microbial interchange in SARA-affected goats.A microbiota transplant experiment verified SARA microbiota’s ability to induce pH decline,escalate inflammation-related gene expression(MAPK10,IL17B,FOSB,SPP1),disrupt microbial transfer,and reduce Prevotellaceae_UCG-003 in recipients.Conclusion Our findings highlight SARA’s dual impact on ruminal and buccal microbiota,exacerbating epithelial inflammation gene expression.Shifts in the buccal microbiome,specifically reductions in Prevotellaceae_UCG-003,mirror ruminal changes and can be influenced by inter-compartmental bacterial transmission,thereby offering a non-invasive diagnostic approach for SARA.
