Effects of live yeast (Saccharomyces cerevisiae Strain 1026) : supplementation on the closure of articular growth plates in quarter horse foals

Abstract

Abstract: The objective of this study was to determine whether dietary live yeast (Saccharomyces cerevisiae strain 1026) was able to shorten the time for growth plate closure. Twenty-four Quarter Horse foals, 8 months of age, were allotted to 2 treatment groups in a completely randomized experimental design. Horses were fed 0 or 20 g live yeast daily from 8 to 24 months of age. Growth plate closure was evaluated by dorso- palmar X – ray imaging at baseline, second study at 12 months of age and finally at 24 months of age. Blood and urine samples were taken at the same time to evaluate bone and mineral metabolism parameters, serum phosphorus, calcium, magnesium, alkaline phosphatase, serum hydroxyproline. Calcium, magnesium and phosphorus urinary fractional excretion were calculated. Closure scales of distal radius growth plate data were compared using the Wilcoxon´s test; bone markers were compared using Student´s t-test. Baseline radiographs showed that in 84% of foals the distal metacarpi were half closed or fully closed at 8 months; thus subsequent evaluations were limited to the distal radius. At 12 months of age, a positive but nonsignificant elevation in calcium urinary fractional excretion was observed in the supplemented group. At 24 months of age, radiographs showed a non-significant but positive effect in the live yeast group, with more than 50% of foals having closed distal radius growth plates. Although bone markers at 24 months of age did not differ (p > 0.05) between groups, some individual horses showed a positive effect with yeast supplementation