Longitudinal Changes in Fecal Microbiota During Hospitalization in Horses With Different Types of Colic.

English. peer reviewed

English. [en] BACKGROUND: Research on fecal microbiota changes during hospitalization of horses with colic is emerging. OBJECTIVES: Describe changes of the fecal microbiota during hospitalization of horses with colic caused by inflammatory (INFL), simple (SIMPLE), and strangulated (STR) obstructions, and investigate associations with survival. ANIMALS: Twenty-three horses with colic: 9 in INFL, 5 in STR, and 9 in SIMPLE groups. Seventeen horses survived, and 6 were euthanized. METHODS: Prospective observational study. Fecal samples were collected on admission (D1), on days 3 (D3) and 5 (D5). Bacterial taxonomy profiling was obtained by V1V3 16S amplicon sequencing. Data were compared using a 2-way permutational analysis of variance (PERMANOVA). Linear discriminant analysis Effect Size (LEfSE) analysis identified significant bacterial population differences, with significance set at p < 0.05 and a linear discriminant analysis (LDA) cut-off > 3.0. RESULTS: Alpha diversity indices remained stable during hospitalization within each colic group. However, at D5, the INFL group had significantly higher richness (p < 0.01) and diversity (Shannon, p < 0.001 and Simpson, p < 0.05) than other colic types. Beta diversity (Jaccard membership and Bray-Curtis indices) was significantly different in the INFL compared to SIMPLE and STR groups (both p < 0.001) but not between SIMPLE and STR. Beta diversity membership analysis by analysis of molecular variance (AMOVA) indicated a significant difference between survivors and non-survivors within the INFL group (p < 0.01). Increased relative abundances of Bacilliculturomica and Saccharofermentans were associated with survival. CONCLUSIONS: Microbiota showed no significant variation over 5 days of hospitalization. Colic type influenced fecal microbiota more than hospitalization duration. Specific bacterial populations may differ between survival and non-survival groups.