Trends in the prevalence of Gidoh at Japan Racing Association Training Centers in 2020.

Overview

• This study investigated the occurrence and characteristics of Gidoh, a pathological hoof-wall condition in racehorses, at Japan Racing Association Training Centers in 2020.
• The research aimed to determine if previous trends from 2001 persisted regarding age, gender, lesion type, location, severity, seasonal variation, and differences between training centers.

Background

• Gidoh is a hoof-wall cavity unrelated to nailing, commonly found in horses’ feet in Japan.
• A 2001 study by the Japan Racing Association (JRA) found Gidoh occurred most frequently at the toe of the fore-hoof, predominantly affecting older horses with no gender differences.
• There was uncertainty about whether these patterns continued and about the predominant pathological types or seasonal variations in prevalence.

Study Objectives

• Assess the current prevalence and characteristics of Gidoh in racehorses at the JRA Training Centers during spring and autumn of 2020.
• Compare results with earlier data from 2001 to identify changes or consistencies in prevalence, lesion location, disease type, severity, and demographic patterns.
• Evaluate if differences existed between the two JRA training centers, suggesting variation in hoof-care techniques.

Methods

• Comprehensive survey carried out in April (spring) and October (autumn) 2020, targeting all racehorses at the JRA training centers.
• Data collected included:
  • Age and gender of horses
  • Location of hoof lesions
  • Type of Gidoh lesions
  • Severity of lesions
  • Overall prevalence of Gidoh

Key Findings

• Age and Gender:
  • Gidoh was most common in horses aged 6 years or older.
  • There was no significant gender predilection, confirming prior findings.
• Lesion Location:
  • The toe area of the fore-hoof remained the most affected site.
• Type and Severity:
  • The predominant pathological type was the white-line-fissure type of Gidoh.
  • Approximately 80% of cases were classified as mild severity.
• Seasonal Variation:
  • The prevalence of Gidoh was significantly lower in October compared to April, indicating some seasonal effect.
  • The statistical significance was supported by a p-value of 0.02.
• Comparison Between Training Centers:
  • No significant difference in prevalence was found between the two JRA training centers.
  • This suggests that hoof-care and management practices have become standardized and aligned at both centers over the past 19 years.
• Comparison With 2001 Data:
  • The overall prevalence pattern and demographic trends in 2020 mirrored those reported in 2001.
  • This similarity suggests stable and consistent hoof management practices at JRA facilities over nearly two decades.

Conclusions

• Gidoh remains a prevalent hoof pathology in older racehorses, predominantly affecting the toe of the fore-hooves with the white-line-fissure type being most common.
• The incidence varies seasonally, being lower in autumn, which could be relevant for management strategies.
• The consistent findings over 19 years demonstrate stable, effective hoof care and management by the JRA.
• The harmonization of care techniques across different training centers is evident, as no center-specific differences in prevalence remain.
• Overall, the research supports the ongoing importance of routine hoof monitoring and management to minimize the impact of Gidoh in racehorses.