Temporal Dynamics of Clinical Response Following Fecal Microbiota Transplantation in Dogs with Chronic Enteropathy

Fecal microbiota transplantation (FMT) is a promising adjunctive treatment for dogs with chronic enteropathy (CE), but response is usually assessed at scheduled follow-up visits, potentially overlooking day-to-day fluctuations. This prospective observational study evaluated temporal response after a single FMT administered by retention enema using daily owner-completed Canine Inflammatory Bowel Disease Activity Index (CIBDAI) monitoring. Fourteen dogs with CE refractory or incompletely responsive to dietary management were enrolled. CIBDAI scores were assigned by a veterinarian at baseline and on days 7 and 30, while owners completed a daily clinical diary for 30 days. Changes over time were assessed using the Friedman test, longitudinal trends using a generalized additive mixed model, and agreement between owner and veterinarian-assigned scores using quadratic-weighted Cohen's kappa and Bland-Altman analysis. Clinician-assigned CIBDAI scores showed a significant overall effect of time (p < 0.01), but no pairwise comparison remained significant after correction. Daily monitoring showed a significant nonlinear pattern in the primary diary-only model, although no interval of significant change was identified. In the secondary baseline-inclusive model, the derivative was significantly negative between Days 2 and 5. In within-dog descriptive comparisons, dogs experienced a median of 3.5 days (range: 0-14) with daily CIBDAI scores at or above their individual T0 value. Weighted kappa was 0.680 (95% CI: 0.266-1.000) at T7 and 0.821 (95% CI: 0.690-0.952) at T30. Bland-Altman analysis identified no proportional bias at T7, whereas significant proportional bias was observed at T30, indicating greater divergence between owner and veterinarian-assigned scores at higher CIBDAI values. Daily owner-reported monitoring captured day-to-day fluctuations that would likely have been missed by conventional outpatient assessments performed only at predefined follow-up time points and may therefore support more individualized post-FMT follow-up in dogs with CE.