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American journal of veterinary research2000; 60(12); 1562-1566;

Epidemiologic analysis of factors influencing exertional rhabdomyolysis in Thoroughbreds.

Abstract: To determine incidence, effect on performance, and management practices associated with exertional rhabdomyolysis (ER) in Thoroughbreds. Methods: Medical records for 984 Thoroughbreds and a survey of trainers of horses with and without ER. Methods: Medical records for 984 Thoroughbreds stabled at a midwestern racetrack were examined to determine the incidence of ER during the 1995 racing season. A retrospective questionnaire was administered to trainers to determine management practices associated with ER in 59 Thoroughbreds with ER and 47 control Thoroughbreds in training. Multiple logistic regression was used to determine management factors associated with ER. Results: ER affected 48 of 984 (4.9%) Thoroughbreds. Two-year-old females were most frequently affected, and 36 of 96 (37.5%) trainers had > or = 1 horse with ER. Horses with ER were more likely not to race during the racing season, compared with control horses. For horses that raced, differences were not found with respect to racing performance between ER and control horses. Exertional rhabdomyolysis developed frequently in susceptible horses that had > or = 1 day of rest prior to exercise and that galloped during exercise. Horses with ER were commonly fed > 4.5 kg of grain daily. Nervous and extremely nervous horses were 5.4 times more likely, and horses with some form of lameness were 4.2 times more likely, to have ER. Conclusions: Exertional rhabdomyolysis is common in Thoroughbreds, and ER can be affected by temperament, sex, age, diet, exercise routines, and lameness. Management that minimizes excitability, particularly when tailored to each horse, may be most effective for controlling ER.
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Publication Date: 2000-01-06 PubMed ID: 10622169
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  • Journal Article
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  • Non-U.S. Gov't

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.

This research tries to comprehend the incidence, effect on performance, and management practices related to exertional rhabdomyolysis (a muscle disorder) in Thoroughbreds. Analyzing the medical records of 984 Thoroughbreds and surveying horse trainers, the study identifies various factors such as temperament, age, sex, diet, exercise routines, and lameness influencing the disorder.

Epidemiologic Analysis of Exertional Rhabdomyolysis

  • The study was carried out to discern the incidence of exertional rhabdomyolysis in Thoroughbreds, along with its effects on performance and the management practices connected with it.
  • The data for the research was gathered from the medical records of 984 Thoroughbreds at a Midwestern racetrack to find out the prevalence of exertional rhabdomyolysis during the 1995 racing season.
  • Findings reveal that around 4.9% of Thoroughbreds suffered from exertional rhabdomyolysis, with two-year-old females being the most susceptible.
  • The study also informs that 37.5% of trainers had at least one horse with this condition.

Impact on Racing Performance

  • The study found that horses with exertional rhabdomyolysis were more likely to not participate in races during the racing season when compared to control horses (those without the condition).
  • Interestingly, among the horses that did participate in races, no significant difference was found in their performance levels, irrespective of whether or not they had exertional rhabdomyolysis.

Role of Management Practices and Other Factors

  • A retrospective questionnaire was used to find out the management practices associated with exertional rhabdomyolysis in 59 Thoroughbreds.
  • The horses that were more prone to exertional rhabdomyolysis had distinct patterns – they had been off exercising for at least one day before participating and preferred galloping during exercise.
  • There appeared to be a correlation between the amount of grain fed to the horses and their vulnerability to exertional rhabdomyolysis. The condition was more common in horses fed more than 4.5 kg of grain daily.
  • In terms of personality traits, the research showed that nervous and extremely nervous horses were 5.4 times more likely to have exertional rhabdomyolysis.
  • Another factor that increased susceptibility to exertional rhabdomyolysis was some form of lameness, making horses 4.2 times more likely to suffer from the condition.

Conclusion

  • Exertional rhabdomyolysis is a common condition in Thoroughbreds.
  • It can be influenced by many factors including age, sex, diet, training regimen, lameness, and the temperament of the horse.
  • The study suggests that a management strategy aimed at reducing excitability and tailored to each horse’s needs might be the most effective method to control the occurrence of exertional rhabdomyolysis.

Cite This Article

APA
MacLeay JM, Sorum SA, Valberg SJ, Marsh WE, Sorum MD. (2000). Epidemiologic analysis of factors influencing exertional rhabdomyolysis in Thoroughbreds. Am J Vet Res, 60(12), 1562-1566.

Publication

American journal of veterinary research
ISSN: 0002-9645
NlmUniqueID: 0375011
Country: United States
Language: English
Volume: 60
Issue: 12
Pages: 1562-1566

Researcher Affiliations

MacLeay, J M
  • Department of Clinical and Population Sciences, College of Veterinary Medicine, University of Minnesota, St Paul 55108, USA.
Sorum, S A
    Valberg, S J
      Marsh, W E
        Sorum, M D

          MeSH Terms

          • Age Factors
          • Animals
          • Female
          • Horse Diseases / epidemiology
          • Horses
          • Incidence
          • Male
          • Minnesota / epidemiology
          • Retrospective Studies
          • Rhabdomyolysis / epidemiology
          • Rhabdomyolysis / veterinary
          • Sex Factors
          • Surveys and Questionnaires

          Citations

          This article has been cited 20 times.
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