Gastrointestinal flora and serum metabolomic elucidation ofwater decoction intervention in subclinical bovine mastitis.

Abstract

BACKGROUND: This study addresses the global challenge of subclinical bovine mastitis (SCBM) in dairy cows, a prevalent disease causing substantial economic losses, by investigating the mechanistic basis of, a traditional herbal remedy with empirically validated efficacy but incompletely understood modes of action. METHODS: Initially, the active components ofwere identified using LC-MS/MS. Dose-response trials were conducted in Holstein cows (= 24 SCBM cases;= 6 healthy controls), along with multi-omics integration, including 16S rRNA sequencing for rumen/feces microbiota and UHPLC-MS metabolomics for serum analysis. The therapeutic effects of Astragali Radix water decoction (ARWD) on milk production, inflammatory markers, immune parameters, and oxidative stress were systematically evaluated. RESULTS: ARWD administration dose-dependently improved milk yield and protein content while reducing somatic cell counts. Serum pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) decreased, contrasting with increases in immunoglobulins (IgA, IgM, IgG) and enhanced superoxide dismutase activity. Microbiota restructuring featured ruminal enrichment of Bifidobacterium and fecal dominance of Rikenellaceae_RC9_gut_group, coupled with suppression of pro-inflammatory taxa (e.g., Christensenellaceae_R-7_group). Metabolomic analysis identified four ARWD-responsive biomarkers, notably Spirotaccagenin and Pelanin, operating through linoleic acid metabolism and phospholipase D signaling pathways. Strong correlations linked microbial shifts to improved lactation parameters and reduced inflammation. CONCLUSION: The findings establish that ARWD alleviates SCBM through coordinated microbiota remodeling and metabolic reprogramming, specifically enhancing antioxidant defenses, restoring mammary barrier integrity, and modulating immune-inflammation crosstalk, with optimal efficacy at 0.4 g·kg·ddosage. This mechanistic validation positions ARWD as a scientifically grounded, eco-friendly alternative for sustainable mastitis management, reconciling therapeutic effectiveness with agricultural economic priorities.