Effects of fecal microbiota transplantation on clinical outcomes and fecal microbiota of foals with diarrhea

Abstract

Background: Diarrhea in foals can be associated with disruption of the intestinal microbiota (dysbiosis). Effective management of intestinal dysbiosis in foals has not been demonstrated.

Hypothesis/objectives: Fecal microbiota transplantation (FMT) in foals with diarrhea influences the intestinal microbiota and improves clinical and clinicopathological outcomes.

Animals: Twenty-five foals <6 months of age with diarrhea and systemic inflammatory response syndrome at 3 veterinary hospitals.

Methods: A prospective randomized placebo-controlled cohort study. Foals in the FMT group (n = 19) or control group (n = 9) received FMT or electrolyte solution once daily for 3 days. Fecal samples were obtained on Day 0 (D0), D1, D2, D3, and D7. Within group and between group data analyses were performed for clinical, clinicopathological, and microbiota variables.

Results: Treatment had no effect on survival (FMT 79%; control 100%, P = .3) or resolution of diarrhea (FMT 68%; control 55%, P = .4). On D3, the white blood cell count of the FMT group was lower than the control group (D3 FMT group median 6.4 g/L [5-8.3 g/L]; D3 control group median 14.3 g/L [6.7-18.9 g/L] P = .04). Heart rate reduced over time in the FMT group (D0 median 80 bpm [60-150 bpm]; D2 median 70 bpm [52-110 bpm] [P = .005]; and D3 median 64, [54-102 bpm] [P < .001]). Phylum Verrucomicrobiota, genus Akkermansia, and family Prevotellaceae were enriched in the FMT group on D1 (linear discriminate analysis > 4).

Conclusions and clinical importance: In foals with diarrhea, FMT appears safe and can be associated with some clinical and microbiota changes suggestive of beneficial effect.

Keywords: foal; next‐generation sequencing; transplant.

FIGURE 1

Pie chart displaying the identified enteropathogens from foals with diarrhea.

FIGURE 2

WBC and PCV of the FMT group and Control group on D3. FMT, fecal microbiota transplantation; WBC, white blood cell.

FIGURE 3

Line graph displaying the prevalence of diarrhea within the FMT group and the control group during the study period. FMT, fecal microbiota transplantation.

FIGURE 4

The fecal microbiota relative abundance at genus level. The bar chart shows the relative abundance of the donor horses, and each foal group at each sampling time point.

FIGURE 5

The enriched fecal microbiota displayed by LEfSe histogram, which shows a number of differences in taxa at D0. LEfSe, linear discriminant analysis effect size.

FIGURE 6

The enriched fecal microbiota displayed by a LEfSe histogram, which shows enriched features in the FMT group at Day 1 compared with the Control group on Day 1. FMT, fecal microbiota transplantation; LEfSe, linear discriminant analysis effect size.

FIGURE 7

Measures of alpha diversity including Chao1 (A) observed features (B) and Shannon (C) box plot displaying differences in alpha diversity between groups. The donor horses had significantly increased richness and diversity compared with all foals.

FIGURE 8

Weighted (A) and unweighted (B) principal coordinate analysis of the fecal microbiota of foals with diarrhea and adult donor horses. Each shape represents each group at each time point during the study period.