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Home / Equine Research Bank / J Vet Intern Med / Racing-associated fatalities in Norwegian and Swedish harnes...
Journal of veterinary internal medicine2022; 36(2); 778-786; doi: 10.1111/jvim.16364

Racing-associated fatalities in Norwegian and Swedish harness racehorses: Incidence rates, risk factors, and principal postmortem findings.

Abstract: There are no reports on the number of fatalities or causes of death in the Norwegian and Swedish harness racehorses. Objective: The incidence rates (IRs), risk factors, and postmortem findings in horses that died or were euthanized associated with racing between 2014 and 2019 were investigated. Methods: Thirty-eight Standardbreds and 10 Norwegian-Swedish Coldblooded Trotters died or were euthanized associated with racing. A total of 816 085 race-starts were recorded. Methods: Incidence rates were calculated for both countries and horse breeds. Risk factors for sudden death were identified using a case-control logistic model. Postmortem examinations were performed in 43 horses. Results: The overall fatality IR was 0.059/1000 race-starts. Traumatic injuries accounted for 14.5%, while sudden death for 85.5% of fatalities. Only minor differences between countries and breeds were recorded. The number of starts within the last 30 days increased the risk of sudden death (5 starts odds ratio (OR) 228.80, confidence interval (CI) 10.9-4793). An opposite non-linear effect was observed in number of starts the last 180 days (>10 starts OR 0.12, CI 0.02-0.68). Seven horses were euthanized because of catastrophic injury. Acute circulatory collapse because of suspected cardiac or pulmonary failure or both was recorded in 30 horses, while major hemorrhage after vessel rupture was the primary cause of death in 10 cases. One horse collapsed and died but was not submitted for autopsy. Conclusions: Comparatively low rates of catastrophic orthopedic fatalities were reported, while causes and IR of sudden death were similar to previous studies.
© 2022 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.
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Publication Date: 2022-01-21 PubMed ID: 35060194PubMed Central: PMC8965266DOI: 10.1111/jvim.16364Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research explores the incidence rates, risk factors, and causes of death in Norwegian and Swedish harness racehorses during races between 2014 and 2019, from a total of 816,085 race starts.

Methodology

  • In this study, the researchers investigated 48 horses (38 Standardbreds and 10 Norwegian-Swedish Coldblooded Trotters) that died or were euthanized during harness racing.
  • They calculated incidence rates for horse fatalities in both countries and breeds.
  • Using a case-control logistic model, the researchers were able to identify risk factors for sudden death.
  • Postmortem examinations were conducted on 43 of the departed horses.

Findings

  • The overall fatality incidence rate for harness racing horses was found to be 0.059 per 1,000 race starts.
  • 14.5% of fatalities were due to traumatic injuries, while 85.5% were sudden deaths.
  • There was only a minor difference in these statistics between the two countries and breeds studied.
  • The study found that the number of starts a horse made within the 30 days before a fatality significantly increased the risk of sudden death (5 starts led to a 228.80-odds ratio).
  • Interestingly, a nonlinear effect was observed in the number of starts made the last 180 days – fatal incident risk declined with a horse engaging in more than 10 starts
  • Seven horses had to be euthanized due to severe injuries.
  • The most common cause of death was acute circulatory collapse due to suspected cardiac or pulmonary failure (recorded in 30 horses) followed by major hemorrhage after vessel rupture (observed in 10 cases).

Conclusions

The study reports comparatively low rates of catastrophic orthopedic fatalities. The causes and incidence rate of sudden death was found to be similar to previous studies on this topic. The findings indicate that the majority of racing-associated fatalities are due to sudden deaths, with cardiac or pulmonary issues being a key factor.

Cite This Article

APA
Hellings IR, Skjerve E, Karlstam E, Valheim M, Ihler CF, Fintl C. (2022). Racing-associated fatalities in Norwegian and Swedish harness racehorses: Incidence rates, risk factors, and principal postmortem findings. J Vet Intern Med, 36(2), 778-786. https://doi.org/10.1111/jvim.16364

Publication

Journal of veterinary internal medicine
ISSN: 1939-1676
NlmUniqueID: 8708660
Country: United States
Language: English
Volume: 36
Issue: 2
Pages: 778-786

Researcher Affiliations

Hellings, Ingunn Risnes
  • Department of Companion Animal Clinical Sciences, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Ås, Norway.
Skjerve, Eystein
  • Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Ås, Norway.
Karlstam, Erika
  • Department of Pathology and Wildlife Diseases, The Swedish National Veterinary Institute, Uppsala, Sweden.
Valheim, Mette
  • Department of Pathology and High-Risk Pathogens, The Norwegian Veterinary Institute, Ås, Norway.
Ihler, Carl Fredrik
  • Department of Companion Animal Clinical Sciences, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Ås, Norway.
Fintl, Constanze
  • Department of Companion Animal Clinical Sciences, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Ås, Norway.

MeSH Terms

  • Animals
  • Autopsy / veterinary
  • Horses
  • Incidence
  • Risk Factors
  • Sports
  • Sweden / epidemiology

Conflict of Interest Statement

Authors declare no conflict of interest.

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Citations

This article has been cited 3 times.
  1. Nath L, Stent A, Elliott A, La Gerche A, Franklin S. Risk Factors for Exercise-Associated Sudden Cardiac Death in Thoroughbred Racehorses. Animals (Basel) 2022 May 18;12(10).
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  2. Kapusniak A, Lara NM, Hitchens PL, Bailey S, Nath L, Franklin S. Use of Artificial Intelligence to Detect Cardiac Rhythm Disturbances in Athletes: A Scoping Review. J Vet Intern Med 2025 Nov-Dec;39(6):e70257.
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  3. Avison A, Goderre BG, Pyle WG, Physick-Sheard PW. QT Interval and Cardiac Restitution Ratio Complexity in Standardbred Racehorses From Rest to Maximal Effort: Insights Into Arrhythmia Risk. J Vet Intern Med 2025 Sep-Oct;39(5):e70207.
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