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farriery
veterinary
biomechanics
anatomy
nutrition
physiotherapy
2012
Cohort Study

Relative prevalence of upper respiratory tract obstructive disorders in two breeds of harness racehorses (185 cases: 1998-2006).

Authors: Strand E, Fjordbakk C T, Sundberg K, Spangen L, Lunde H, Hanche-Olsen S

Journal: Equine veterinary journal

Summary

# Editorial Summary Upper respiratory tract obstructions significantly compromise performance in harness racehorses, yet breed-specific prevalence data have been lacking—particularly for the genetically distinct Standardbred and Coldblooded Trotter breeds used in Scandinavian racing. By examining 185 cases diagnosed between 1998 and 2006, researchers compared obstruction rates between these two breeds whilst controlling for environmental and management variables, since both populations compete under identical conditions. The findings revealed substantial breed-level differences in susceptibility to specific URT disorders, suggesting genetic factors play a substantial role in determining which horses develop these performance-limiting conditions. For practitioners working across different breeds, these results underscore the importance of targeted diagnostic screening protocols and highlight that breed predisposition—rather than training or management alone—may explain variable presentations of obstruction in racehorses. Understanding these breed-specific vulnerabilities allows farriers, veterinarians and trainers to establish more informed early intervention strategies and realistic performance expectations.

Read the full abstract on PubMed

Practical Takeaways

  • When evaluating harness racehorses for poor performance or respiratory noise, consider breed-specific susceptibility patterns to URT obstructions as part of diagnostic approach
  • Standardbred and Coldblooded Trotter horses may require breed-tailored screening protocols for different types of URT obstructive disorders
  • Genetic factors play a significant role in URT obstruction risk; breeding decisions should account for breed predispositions to these conditions

Key Findings

  • Study compared URT obstructive disorder prevalence between Standardbred and Coldblooded Trotter harness racehorses under identical environmental and racing conditions
  • Genetic and phenotypic differences between breeds were associated with different relative prevalences of specific URT obstructive conditions
  • Findings suggest breed-specific predisposition to certain upper respiratory tract disorders independent of management and training variables

Conditions Studied

upper respiratory tract obstructive disordersrecurrent laryngeal neuropathydorsal displacement of the soft palateepiglottic entrapmentsubepiglottic cyst

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