Dates: October 2018 - December 2020

Background: Heatstroke is a potentially fatal, yet often preventable, condition for dogs that can be caused by exercise (exertional heatstroke), or confinement in hot conditions (environmental heatstroke) (Bruchim et al. 2017). Despite the annual “Dogs die in hot cars” campaign, the number of calls made to the RSPCA reporting animals in hot environments grew by 10% from 2016 to 2017. Other evidence also suggests the number of canine heatstroke cases is increasing; the number of British vets reporting treating heat related conditions increased significantly from 2015 to 2016, with 25% of vets reporting seeing up to eight cases during the summer of 2016 (BVA, 2017).  

Canine heatstroke studies from USA, Germany and Israel, report fatality rates from 36% to 63%, with all studies reporting more male than female dogs affected (Hall and Carter, 2016). Obesity, respiratory disease and lack of fitness have also been reported as risk factors for heatstroke in dogs outside of the UK (Bruchim et al. 2017). These findings are particularly pertinent to the UK as two of these risk factors: canine sports participation (Carter and Hall, 2018) and brachycephalic breed ownership (O’Neill et al. 2016; O’Neill et al. 2018), have increased within the UK dog population in recent years. However, to date there have been no published studies investigating canine heatstroke cases in the UK, meaning the incidence and risk factors for this high-welfare disorder in UK dogs are currently unknown.  

This project will use the VetCompass™ database to review the clinical records of over 900,000 dogs registered with UK primary-care veterinary practices for heatstroke events. As well as canine risk factors (e.g. breed, age, sex and bodyweight), additional information will be collected to establish the incidence, fatality rate, seasonality and underlying causes for heatstroke. Understanding the risk factors of heatstroke specific to the UK dog population will provide evidence to better support educational campaigns aiming to reduce or prevent this potentially fatal condition.


  • To report the incidence of canine heatstroke cases presenting to primary care veterinary practices in the United Kingdom.
  • To determine canine factors associated with increased risk of heatstroke.
  • To identify the predominant underlying cause of canine heatstroke in the United Kingdom (exertional versus environmental heatstroke).


British Veterinary Association (2017). Vet warning for pets as summer heat returns London: British Veterinary Association. [Available from:  

Bruchim et al. (2017). Pathophysiology of heatstroke in dogs – revisited. Temperature. 4, 56-70.  

Carter & Hall (2018). Investigating factors affecting the body temperature of dogs competing in cross country (canicross) races in the UK. Journal of Thermal Biology 72, 33-8.  

Hall & Carter (2016). Heatstroke – providing evidence-based advice to dog owners. Veterinary Nursing Journal 31. 359-63.  

O'Neill et al. (2018). Demography and disorders of the French Bulldog population under primary veterinary care in the UK in 2013. Canine Genetics and Epidemiology 5, 3.  

  O'Neill et al. (2016). Demography and health of Pugs under primary veterinary care in England. Canine Genetics and Epidemiology 3, 1-12.

Vet Compass Project Type: Dog

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