FREE SHIPPING over $40
OVER 9000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Home / Equine Research Bank / Equine Vet J / Causes of death in racehorses over a 2 year period.
Equine veterinary journal1994; 26(4); 327-330; doi: 10.1111/j.2042-3306.1994.tb04395.x

Causes of death in racehorses over a 2 year period.

Abstract: Necropsies were performed on 496 horses that had a fatal injury or illness at a California racetrack during the period February 20th 1990 to March 1st 1992. The primary cause of death was categorised by breed, activity at time of injury or illness and organ system affected. Most of the submissions were Thoroughbred horses (432) and Quarter Horses (46). Most of the injuries occurred while racing (42%) and in training sessions (39%); with fewer non-exercise (12%) and accident (7%) related injuries or illnesses. Musculoskeletal injuries accounted for 83% of the Thoroughbred and 80% of the Quarter Horse submissions. The Thoroughbred horses incurred 306 fractures with 263 in the limbs and 90% of those in the forelimbs. The proximal sesamoid bone(s), third metacarpal bone and humerus were the most common bones fractured in Thoroughbred horses and Quarter Horses. Other major causes of death included respiratory, digestive and multi-organ system disorders.
Get Full Text
Publication Date: 1994-07-01 PubMed ID: 8575402DOI: 10.1111/j.2042-3306.1994.tb04395.xGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • 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 investigates the primary causes of death in racehorses, particularly Thoroughbreds and Quarter Horses, over a two-year period in a California racetrack. It identified musculoskeletal injuries and fractures as the major causes, most of which were sustained during races and training sessions.

Objective and Methods

  • The research aimed to understand the major causes of death in racehorses at a California racetrack from February 20, 1990, to March 1, 1992.
  • To achieve this, necropsies were conducted on 496 horses who either had a fatal injury or illness during this period.
  • The investigators categorized the primary cause of death according to the breed of the horse, the horse’s activity at the time of injury or illness, and the affected organ system.

Key Findings

  • The majority of the studied horses were Thoroughbreds (432) and Quarter Horses (46)
  • A significant number of injuries occurred during racing (42%) or training sessions (39%); on the other hand, non-exercise activities and accidents accounted for fewer injuries and illnesses (12% and 7% respectively).
  • Musculoskeletal injuries were the predominant cause of death, accounting for 83% of the Thoroughbred cases and 80% of the Quarter Horse submissions.
  • In the case of Thoroughbred horses, the study identified that they incurred 306 fractures, of which 263 were located in the limbs. About 90% of these limb fractures were situated in the forelimbs.
  • The most common bones to fracture were the proximal sesamoid bones, third metacarpal bone, and the humerus in both Thoroughbred and Quarter Horses.

Other Causes of Death

  • Apart from musculoskeletal injuries and fractures, the research also pinpointed other significant causes of death in horses.
  • These included respiratory and digestive system disorders along with multi-organ system disorders.

Conclusion

  • The research provides valuable insight into the major causes of death in racehorses over a particular time frame.
  • Notably, it emphasizes the prevalence of musculoskeletal issues, particularly fractures, primarily sustained during racing and training sessions.
  • The findings pave the way for further studies on developing effective prevention and response measures to these prevalent issues in racehorses.

Cite This Article

APA
Johnson BJ, Stover SM, Daft BM, Kinde H, Read DH, Barr BC, Anderson M, Moore J, Woods L, Stoltz J. (1994). Causes of death in racehorses over a 2 year period. Equine Vet J, 26(4), 327-330. https://doi.org/10.1111/j.2042-3306.1994.tb04395.x

Publication

Equine veterinary journal
ISSN: 0425-1644
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 26
Issue: 4
Pages: 327-330

Researcher Affiliations

Johnson, B J
  • California Veterinary Diagnostic Laboratory System.
Stover, S M
    Daft, B M
      Kinde, H
        Read, D H
          Barr, B C
            Anderson, M
              Moore, J
                Woods, L
                  Stoltz, J

                    MeSH Terms

                    • Age Factors
                    • Animals
                    • Breeding
                    • Cause of Death
                    • Digestive System Diseases / epidemiology
                    • Digestive System Diseases / mortality
                    • Digestive System Diseases / veterinary
                    • Female
                    • Fractures, Bone / epidemiology
                    • Fractures, Bone / mortality
                    • Fractures, Bone / veterinary
                    • Horse Diseases / epidemiology
                    • Horse Diseases / mortality
                    • Horses / injuries
                    • Incidence
                    • Lung Diseases / epidemiology
                    • Lung Diseases / mortality
                    • Lung Diseases / veterinary
                    • Male

                    Citations

                    This article has been cited 41 times.
                    1. Noordwijk KJ, Chen L, Ruspi BD, Schurer S, Papa B, Fasanello DC, McDonough SP, Palmer SE, Porter IR, Basran PS, Donnelly E, Reesink HL. Metacarpophalangeal Joint Pathology and Bone Mineral Density Increase with Exercise but Not with Incidence of Proximal Sesamoid Bone Fracture in Thoroughbred Racehorses. Animals (Basel) 2023 Feb 24;13(5).
                      doi: 10.3390/ani13050827pubmed: 36899684google scholar: lookup
                    2. Shaffer SK, Stover SM, Fyhrie DP. Training drives turnover rates in racehorse proximal sesamoid bones. Sci Rep 2023 Jan 27;13(1):205.
                      doi: 10.1038/s41598-022-26027-ypubmed: 36707527google scholar: lookup
                    3. Basran PS, McDonough S, Palmer S, Reesink HL. Radiomics Modeling of Catastrophic Proximal Sesamoid Bone Fractures in Thoroughbred Racehorses Using μCT. Animals (Basel) 2022 Nov 4;12(21).
                      doi: 10.3390/ani12213033pubmed: 36359157google scholar: lookup
                    4. Pearce DJ, Hitchens PL, Malekipour F, Ayodele B, Lee PVS, Whitton RC. Biomechanical and Microstructural Properties of Subchondral Bone From Three Metacarpophalangeal Joint Sites in Thoroughbred Racehorses. Front Vet Sci 2022;9:923356.
                      doi: 10.3389/fvets.2022.923356pubmed: 35847629google scholar: lookup
                    5. Crawford KL, Ahern BJ. Investigations into Thoroughbred racehorse welfare in Queensland Australia focused on musculoskeletal injuries and retirement. Anim Front 2022 Jun;12(3):59-62.
                      doi: 10.1093/af/vfac018pubmed: 35711502google scholar: lookup
                    6. Bowers K, Weinhandl JT, Anderson DE. A review of equine tibial fractures. Equine Vet J 2023 Mar;55(2):171-181.
                      doi: 10.1111/evj.13599pubmed: 35569040google scholar: lookup
                    7. Hellings IR, Skjerve E, Karlstam E, Valheim M, Ihler CF, Fintl C. Racing-associated fatalities in Norwegian and Swedish harness racehorses: Incidence rates, risk factors, and principal postmortem findings. J Vet Intern Med 2022 Mar;36(2):778-786.
                      doi: 10.1111/jvim.16364pubmed: 35060194google scholar: lookup
                    8. Crawford KL, Finnane A, Greer RM, Barnes TS, Phillips CJC, Woldeyohannes SM, Bishop EL, Perkins NR, Ahern BJ. Survival Analysis of Training Methodologies and Other Risk Factors for Musculoskeletal Injury in 2-Year-Old Thoroughbred Racehorses in Queensland, Australia. Front Vet Sci 2021;8:698298.
                      doi: 10.3389/fvets.2021.698298pubmed: 34796223google scholar: lookup
                    9. Samol MA, Uzal FA, Blanchard PC, Arthur RM, Stover SM. Sudden death caused by spinal cord injury associated with vertebral fractures and fetlock failure in a Thoroughbred racehorse. J Vet Diagn Invest 2021 Jul;33(4):788-791.
                      doi: 10.1177/10406387211018289pubmed: 34041971google scholar: lookup
                    10. Physick-Sheard P, Avison A, Sears W. Factors Associated with Mortality in Ontario Standardbred Racing: 2003-2015. Animals (Basel) 2021 Apr 5;11(4).
                      doi: 10.3390/ani11041028pubmed: 33916415google scholar: lookup
                    11. Crawford KL, Finnane A, Phillips CJC, Greer RM, Woldeyohannes SM, Perkins NR, Kidd LJ, Ahern BJ. The Risk Factors for Musculoskeletal Injuries in Thoroughbred Racehorses in Queensland, Australia: How These Vary for Two-Year-Old and Older Horses and with Type of Injury. Animals (Basel) 2021 Jan 21;11(2).
                      doi: 10.3390/ani11020270pubmed: 33494508google scholar: lookup
                    12. Ribitsch I, Oreff GL, Jenner F. Regenerative Medicine for Equine Musculoskeletal Diseases. Animals (Basel) 2021 Jan 19;11(1).
                      doi: 10.3390/ani11010234pubmed: 33477808google scholar: lookup
                    13. Crawford KL, Ahern BJ, Perkins NR, Phillips CJC, Finnane A. The Effect of Combined Training and Racing High-Speed Exercise History on Musculoskeletal Injuries in Thoroughbred Racehorses: A Systematic Review and Meta-Analysis of the Current Literature. Animals (Basel) 2020 Nov 11;10(11).
                      doi: 10.3390/ani10112091pubmed: 33187122google scholar: lookup
                    14. Crawford KL, Finnane A, Greer RM, Phillips CJC, Woldeyohannes SM, Perkins NR, Ahern BJ. Appraising the Welfare of Thoroughbred Racehorses in Training in Queensland, Australia: The Incidence and Type of Musculoskeletal Injuries Vary between Two-Year-Old and Older Thoroughbred Racehorses. Animals (Basel) 2020 Nov 5;10(11).
                      doi: 10.3390/ani10112046pubmed: 33167429google scholar: lookup
                    15. Bellone RR, Ocampo NR, Hughes SS, Le V, Arthur R, Finno CJ, Penedo MCT. Warmblood fragile foal syndrome type 1 mutation (PLOD1 c.2032G>A) is not associated with catastrophic breakdown and has a low allele frequency in the Thoroughbred breed. Equine Vet J 2020 May;52(3):411-414.
                      doi: 10.1111/evj.13182pubmed: 31502696google scholar: lookup
                    16. Tapprest J, Foucher N, Linster M, Laloy E, Cordonnier N, Amat JP, Hendrikx P. Resumeq: A Novel Way of Monitoring Equine Diseases Through the Centralization of Necropsy Data. Front Vet Sci 2019;6:135.
                      doi: 10.3389/fvets.2019.00135pubmed: 31134214google scholar: lookup
                    17. Brown HR, Peloso JG, Werner WC, Mecholsky JJ, Cohen ND, Vogler JB. A Thoroughbred racehorse with a unicortical palmar lateral condylar fracture returned to training 14 days after surgery: a hypothesis on the role of a single bone screw on crack propagation. J Equine Sci 2019 Mar;30(1):7-12.
                      doi: 10.1294/jes.30.7pubmed: 30944541google scholar: lookup
                    18. Spargo KE, Rubio-Martinez LM, Wheeler DP, Fletcher L, Carstens A. Catastrophic musculoskeletal injuries in Thoroughbred racehorses on racetracks in Gauteng, South Africa. J S Afr Vet Assoc 2019 Feb 28;90(0):e1-e5.
                      doi: 10.4102/jsava.v90i0.1640pubmed: 30843400google scholar: lookup
                    19. Turlo AJ, Cywinska A, Frisbie DD. Revisiting predictive biomarkers of musculoskeletal injury in thoroughbred racehorses: longitudinal study in polish population. BMC Vet Res 2019 Feb 26;15(1):66.
                      doi: 10.1186/s12917-019-1799-7pubmed: 30808359google scholar: lookup
                    20. Hitchens PL, Hill AE, Stover SM. Relationship Between Historical Lameness, Medication Usage, Surgery, and Exercise With Catastrophic Musculoskeletal Injury in Racehorses. Front Vet Sci 2018;5:217.
                      doi: 10.3389/fvets.2018.00217pubmed: 30246014google scholar: lookup
                    21. Rosanowski SM, Chang YM, Stirk AJ, Verheyen KLP. Risk factors for race-day fatality in flat racing Thoroughbreds in Great Britain (2000 to 2013). PLoS One 2018;13(3):e0194299.
                      doi: 10.1371/journal.pone.0194299pubmed: 29561898google scholar: lookup
                    22. Maeda Y, Hanada M, Oikawa MA. Epidemiology of racing injuries in Thoroughbred racehorses with special reference to bone fractures: Japanese experience from the 1980s to 2000s. J Equine Sci 2016;27(3):81-97.
                      doi: 10.1294/jes.27.81pubmed: 27703403google scholar: lookup
                    23. Turley SM, Thambyah A, Riggs CM, Firth EC, Broom ND. Microstructural changes in cartilage and bone related to repetitive overloading in an equine athlete model. J Anat 2014 Jun;224(6):647-58.
                      doi: 10.1111/joa.12177pubmed: 24689513google scholar: lookup
                    24. Seo JP, Tsuzuki N, Haneda S, Yamada K, Furuoka H, Tabata Y, Sasaki N. Osteoinductivity of gelatin/β-tricalcium phosphate sponges loaded with different concentrations of mesenchymal stem cells and bone morphogenetic protein-2 in an equine bone defect model. Vet Res Commun 2014 Mar;38(1):73-80.
                      doi: 10.1007/s11259-013-9587-5pubmed: 24442646google scholar: lookup
                    25. Vos Nj. Conservative treatment of a comminuted cervical fracture in a racehorse. Ir Vet J 2008 Apr 1;61(4):244-7.
                      doi: 10.1186/2046-0481-61-4-244pubmed: 21851712google scholar: lookup
                    26. Boyde A, Firth EC. Articular calcified cartilage canals in the third metacarpal bone of 2-year-old thoroughbred racehorses. J Anat 2004 Dec;205(6):491-500.
                      doi: 10.1111/j.0021-8782.2004.00354.xpubmed: 15610396google scholar: lookup
                    27. Leblond A, Villard I, Leblond L, Sabatier P, Sasco AJ. A retrospective evaluation of the causes of death of 448 insured French horses in 1995. Vet Res Commun 2000 Mar;24(2):85-102.
                      doi: 10.1023/a:1006408522233pubmed: 10720095google scholar: lookup
                    28. Pan M, Malekipour F, Pivonka P, Morrice-West AV, Flegg JA, Whitton RC, Hitchens PL. A mathematical model of metacarpal subchondral bone adaptation, microdamage and repair in racehorses. J R Soc Interface 2025 Oct;22(231):20250297.
                      doi: 10.1098/rsif.2025.0297pubmed: 41027486google scholar: lookup
                    29. Zhang Z, Li J, Mai Z, Yang Y, Fu H, Cao X, Li T, Guo Q, Ma Y. Clinical study on the effect of low-intensity pulsed ultrasound on healing of proximal sesamoid bone fractures in Yili horses. Sci Rep 2025 Aug 28;15(1):31697.
                      doi: 10.1038/s41598-025-17424-0pubmed: 40877380google scholar: lookup
                    30. Schild CO, Nyaoke A, Asin J, Henderson EE, Blea JA, Stover SM, Uzal FA. A retrospective study of radial fractures in racehorses in California, 2006-2022. J Vet Diagn Invest 2025 Jul 23;:10406387251336267.
                      doi: 10.1177/10406387251336267pubmed: 40702641google scholar: lookup
                    31. Irandoust S, Whitton C, Henak C, Muir P. Tuning and validation of a virtual mechanical testing pipeline for condylar stress fracture risk assessment in Thoroughbred racehorses. R Soc Open Sci 2025 May;12(5):241935.
                      doi: 10.1098/rsos.241935pubmed: 40370600google scholar: lookup
                    32. Ciamillo SA, Bills KW, Gassert TM, Richardson DW, Brown KA, Stefanovski D, Ortved KF. Effect of high-speed exercise on subchondral bone in the metacarpo-/metatarsophalangeal joints of 2-year-old Thoroughbred racehorses in their first year of training. Equine Vet J 2026 Jan;58(1):40-48.
                      doi: 10.1111/evj.14524pubmed: 40323137google scholar: lookup
                    33. Morrice-West AV, Thomas M, Wong ASM, Flash M, Whitton RC, Hitchens PL. Linkage of jockey falls and injuries with racehorse injuries and fatalities in Thoroughbred flat racing in Victoria, Australia. Front Vet Sci 2024;11:1481016.
                      doi: 10.3389/fvets.2024.1481016pubmed: 40018508google scholar: lookup
                    34. Orozco Lopez D, Garcia-Lopez JM, Carpenter R, Bras JJ, Richardson DW, Ortved KF. Treatment of traumatic disruption of the suspensory apparatus in Thoroughbred racehorses at risk of proximal interphalangeal joint subluxation using a locking compression-distal femur plate for double arthrodesis. Vet Surg 2025 Apr;54(3):439-452.
                      doi: 10.1111/vsu.14219pubmed: 39895425google scholar: lookup
                    35. Bogossian PM, Nattala U, Wong ASM, Morrice-West AV, Zhang GZ, Rana P, Whitton RC, Hitchens PL. A machine learning approach to identify stride characteristics predictive of musculoskeletal injury, enforced rest and retirement in Thoroughbred racehorses. Sci Rep 2024 Nov 22;14(1):28967.
                      doi: 10.1038/s41598-024-79071-1pubmed: 39578597google scholar: lookup
                    36. Irandoust S, O'Neil LM, Stevenson CM, Franseen FM, Ramzan PHL, Powell SE, Brounts SH, Loeber SJ, Ergun DL, Whitton RC, Henak CR, Muir P. Comparison of radiography and computed tomography for identification of third metacarpal structural change and associated assessment of condylar stress fracture risk in Thoroughbred racehorses. Equine Vet J 2025 May;57(3):723-736.
                      doi: 10.1111/evj.14131pubmed: 39143731google scholar: lookup
                    37. Lin ST, Foote AK, Bolas NM, Sargan DR, Murray RC. Histological and Histopathological Features of the Third Metacarpal/Tarsal Parasagittal Groove and Proximal Phalanx Sagittal Groove in Thoroughbred Horses with Racing History. Animals (Basel) 2024 Jun 30;14(13).
                      doi: 10.3390/ani14131942pubmed: 38998057google scholar: lookup
                    38. Ayodele BA, Pagel CN, Mackie EJ, Armour F, Yamada S, Zahra P, Courtman N, Whitton RC, Hitchens PL. Differences in bone turnover markers and injury risks between local and international horses: A Victorian Spring Racing Carnival study. Equine Vet J 2025 Mar;57(2):333-346.
                      doi: 10.1111/evj.14098pubmed: 38634210google scholar: lookup
                    39. Domańska-Kruppa N, Wierzbicka M, Stefanik E. Advances in the Clinical Diagnostics to Equine Back Pain: A Review of Imaging and Functional Modalities. Animals (Basel) 2024 Feb 23;14(5).
                      doi: 10.3390/ani14050698pubmed: 38473083google scholar: lookup
                    40. Nagy A, Boros K, Dyson S. Magnetic Resonance Imaging, Computed Tomographic and Radiographic Findings in the Metacarpophalangeal Joints of 40 Non-Lame Thoroughbred Yearlings. Animals (Basel) 2023 Nov 9;13(22).
                      doi: 10.3390/ani13223466pubmed: 38003084google scholar: lookup
                    41. Wong ASM, Morrice-West AV, Hitchens PL, Whitton RC. The association between Thoroughbred racehorse training practices and musculoskeletal injuries in Victoria, Australia. Front Vet Sci 2023;10:1260554.
                      doi: 10.3389/fvets.2023.1260554pubmed: 37941814google scholar: lookup
                    Subscribe to our newsletter
                    Join 99,357 horse owners like you who receive our email updates on horse health and nutrition.