Prevalence of post-race exertional heat illness in Thoroughbred racehorses and climate conditions at racecourses in Japan.
Abstract: Despite growing recognition of post-race exertional heat illness (EHI) in the horse racing industry, reports on its prevalence are limited. The purpose of this study was to investigate the prevalence of post-race EHI and climate conditions at racecourses in Japan. The overall prevalence of EHI from 1999 to 2018 was 0.04% (387 cases for 975,247 starters) in races operated by the Japan Racing Association (JRA). The yearly prevalence has been increasing, exceeding 0.07% in the last four years of the studied period. The overall prevalence in summer (May-September) was 0.086% (352 cases for 409,908 starters). The monthly prevalence varied among the 10 JRA racecourses, which are distributed from latitude 34 to 43°N, ranging from no cases to 0.459%. During summer, prevalence of post-race EHI was high when the mean monthly ambient temperature was high at a racecourse. To evaluate climate conditions, we investigated the wet-bulb globe temperature (WBGT, °C) from 9 AM to 5 PM on sunny race days in July and August of 2017 and 2018 at three racecourses with a high prevalence of EHI among the 10 racecourses. The durations of time during which WBGT was between 28 and 33°C at these three courses were 95, 94, and 65% of the minutes measured, respectively. This result indicated that most races on the sunny summer days were held when WBGT was between 28 and 33°C at the three racecourses. These findings could be useful in developing the appropriate countermeasures to be taken during hot weather at each of the studied racecourses.
Publication Date: 2019-07-03 PubMed ID: 31285689PubMed Central: PMC6606451DOI: 10.1294/jes.30.17Google Scholar: Lookup
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- Journal Article
Summary
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This study investigates the rate and conditions of exertional heat illness (EHI) in racehorses in Japan, finding an overall prevalence of 0.04% from 1999 to 2018, with rates increasing yearly and particularly during summer months. Climate conditions were evaluated with regards to this illness as well as the potential development of countermeasures.
Objective and Methodology
- The purpose was to evaluate the prevalence of post-race exertional heat illness (EHI) in Thoroughbred racehorses and examine the climate conditions at different racing venues in Japan. The researchers want to develop a comprehension of EHI in order to be able to create effective countermeasures for health risks in horses due to weather conditions.
- The prevalence rates were gathered from data for races conducted by the Japan Racing Association (JRA) during the period of 1999 and 2018.
- To understand the impact of climate on EHI prevalence, conditions were examined based on the wet-bulb globe temperature (WBGT), a composite temperature used to estimate the effect of temperature, humidity, and sunlight on humans.
Findings
- Across the study period, there were 387 cases of EHI, representing an overall prevalence of 0.04% from approximately 975,247 race starts. There has, however, been a trend of increasing yearly prevalence, which surpassed 0.07% in the final four years of the study’s period.
- There is a clear seasonal pattern in EHI events with the prevalence in summer months (May-September) standing at 0.086% (352 cases from around 409,908 starters).
- The EHI rates were higher in summertime when the mean monthly ambient temperature was high.
- The prevalence differed among the 10 JRA racecourses, which are spread out across varying latitudes. Rates ranged from no incidences of EHI at some venues to a prevalence of 0.459% at others.
Implication of the Findings
- The results provide valuable insight into the contexts in which EHI is prevalent in racehorses in Japan, and this knowledge could be useful for forming preventative strategies to minimise EHI cases.
- Most races on sunny summer days occurred when WBGT was between 28 and 33°C at the three racecourses. This knowledge provides potential indicators for when races could be most hazardous regarding EHI, which can inform prevention practices.
Cite This Article
APA
Nomura M, Shiose T, Ishikawa Y, Mizobe F, Sakai S, Kusano K.
(2019).
Prevalence of post-race exertional heat illness in Thoroughbred racehorses and climate conditions at racecourses in Japan.
J Equine Sci, 30(2), 17-23.
https://doi.org/10.1294/jes.30.17 Publication
Researcher Affiliations
- The Horse Racing School, Japan Racing Association, Chiba 270-1431, Japan.
- Equine Research Institute, Japan Racing Association, Fukushima 972-8325, Japan.
- Racehorse Clinic, Ritto Training Center, Japan Racing Association, Shiga 520-3085, Japan.
- Racehorse Clinic, Miho Training Center, Japan Racing Association, Ibaraki 300-0493, Japan.
- Racehorse Clinic, Miho Training Center, Japan Racing Association, Ibaraki 300-0493, Japan.
- Racehorse Clinic, Ritto Training Center, Japan Racing Association, Shiga 520-3085, Japan.
References
This article includes 19 references
- Australian PolonFederationn. Heat policy. .
- Brownlow MA, Dart AJ, Jeffcott LB. Exertional heat illness: a review of the syndrome affecting racing Thoroughbreds in hot and humid climates.. Aust Vet J 2016 Jul;94(7):240-7.
- Brownlow M.A., Knight P.K., Suann C.J.. Exertional heat illness in thoroughbred racehorses: observations and treatment in the field. Proc. Int. Conf. Racing Analysts Vet. 2014 20: 13–22.
- Budd GM. Wet-bulb globe temperature (WBGT)--its history and its limitations.. J Sci Med Sport 2008 Jan;11(1):20-32.
- Casa D.J., Roberts W.O.. Consideration for the medical staff: preventing, identifying and treating exertional heat illness. 2003 pp. 169–195 In: Exertional Heat Illnesses, Human Kinetics, Champaign.
- EquestriannAustralian. Hot weather policy. .
- Guthrie AJ, Lund RJ. Thermoregulation. Base mechanisms and hyperthermia.. Vet Clin North Am Equine Pract 1998 Apr;14(1):45-59.
- Hodgson DR, Davis RE, McConaghy FF. Thermoregulation in the horse in response to exercise.. Br Vet J 1994 May-Jun;150(3):219-35.
- Hodgson D.R.. Thermoregulation. 2014 pp. 108–124 In: The Athletic Horse; Principles and Practice of Equine Sports Medicine, 2nd ed. (Hodgson, D.R., McGowan, C.M., and McKeever, K.H. eds.), Saunders-Elsevier, St. Louis.
- JapannMeteorological Agencyn. Climate change monitoring report. .
- Kanda Y. Investigation of the freely available easy-to-use software 'EZR' for medical statistics.. Bone Marrow Transplant 2013 Mar;48(3):452-8.
- Macdonald D.M., Wheeler D.P., Guthrie A.J.. Post race distress syndrome in thoroughbred racing in South Africa. Proc. Int. Conf. Racing Analysts Vet. 2008 17: 1–9.
- McCutcheon L.J., Geor R.J.. Thermoregulation and exercise-associated heat illness. 2004 pp. 919–936 In: Equine Sports Medicine and Surgery: Basic and Clinical Sciences of the Equine Athlete (Hinchcliff, K.W., Kaneps, A.J., and Ger, R.J. eds.), Saunders-Elsevier, St. Louis.
- Ministry of thenEnvironment Government of Japann. Wet-bulb globe temperature (WBGT). .
- Ministry of thenEnvironment Government of Japann. Synthesis reports in observations, projections and impact assessmentsnof climate change “Climate change in Japan and its impacts”. .
- Schroter RC, Marlin DJ, Jeffcott LB. Use of the Wet Bulb Globe Temperature (WBGT) index to quantify environmental heat loads during three-day-event competitions.. Equine Vet J Suppl 1996 Jul;(22):3-6.
- Thoroughbred RacingnNorthern Territory. Racing horses in hot weather. Policy No.14. .
- Racing and WageringnWestern Australian. Racing horses in hot weather. .
- Racing N.S.W.n. Racing in hot weather policy. .
Citations
This article has been cited 5 times.- Lisboa BRF, da Silva JAR, da Silva WC, Barbosa AVC, Silva LKX, Lourenço-Júnior JB. Evaluation of thermoregulation of horses (Equus caballus) submitted to two methods of post-exercise cooling, in hot and humid climate conditions, in the Eastern Amazon. Front Vet Sci 2023;10:1150763.
- Trigg LE, Lyons S, Mullan S. Risk factors for, and prediction of, exertional heat illness in Thoroughbred racehorses at British racecourses. Sci Rep 2023 Mar 14;13(1):3063.
- Brownlow M, Mizzi JX. An Overview of Exertional Heat Illness in Thoroughbred Racehorses: Pathophysiology, Diagnosis, and Treatment Rationale. Animals (Basel) 2023 Feb 9;13(4).
- Verdegaal EJMM, Howarth GS, McWhorter TJ, Delesalle CJG. Is Continuous Monitoring of Skin Surface Temperature a Reliable Proxy to Assess the Thermoregulatory Response in Endurance Horses During Field Exercise?. Front Vet Sci 2022;9:894146.
- Verdegaal EJMM, Howarth GS, McWhorter TJ, Delesalle CJG. Thermoregulation during Field Exercise in Horses Using Skin Temperature Monitoring. Animals (Basel) 2023 Dec 30;14(1).
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