Cover image courtesy of The Image Is Everything
The conversation over racing in hot weather is something that often rears its head and with equine welfare at the forefront of the wider community’s mind, it is hardly surprising to see the debate again front and centre. While the challenge of rising temperatures cannot be ignored, all industry participants are responsible for ensuring the safe continuation of racing in warm weather.
Risk factors for heat stress
Australia has faced hot summers in the past, but recent trends indicate longer, and more severe weather patterns are ahead of us. To understand the physiological effects of heat on horses, we sought insights from Dr David Marlin, one of the equine world’s leading scientists renowned for his work in equine thermoregulation, and Dr. Meta Osborne, a highly respected equine veterinarian who has an academic focus on animal welfare.
Both Dr Marlin and Dr Meta Osborne emphasised crucial factors that contribute to heat stress in horses.
Dr Marlin highlighted “high temperatures, heavy ground, and the duration of races in hot conditions as primary risk factors for heat-illness in horses.”
“High temperatures, heavy ground, and the duration of races in hot conditions as primary risk factors for heat-illness in horses.” - Dr David Marlin
Additionally, Dr Osborne emphasised the significance of humidity, and the horse's fitness, intensity of exercise, and its duration play pivotal roles in how well the horse copes with heat stress.
As top-tier horses often start their Autumn campaigns amid the height of summer, their fitness levels could significantly affect their ability to endure the prevailing conditions. Dr Marlin indicated that “the start of the season, either for flat or jumps, was a risk factor for heat-related stress and this came down largely to their reduced fitness in the early part of their campaign”.
Dr David Marlin | Image courtesy of Dr David Marlin
Long-distance travel is an unavoidable aspect of horse transportation in Australia due to its vast geography. Research indicates that temperatures inside a horse float on a warm day can be notably higher - 5 to 9.5 degrees - than the outside temperature.
Dr. Marlin emphasises the physiological toll of road travel on horses: “Horses use more energy being transported by roads than standing in their stables to maintain their balance. Obviously, the hotter it is, the more they're going to sweat. And if you have dry heat, then often people don't appreciate how much water horses can be losing.”
The combination of long distances and hot conditions are a recipe for disaster.
“The hotter it is and the further you have to transport, the more that's going to have a negative effect on your horse's performance and potentially also increase the risk of heat-related illness,” said Dr Marlin.
Earlier starts well-received
The modifications to race scheduling in response to forecasted high temperatures were crucial during last weekend's racing events and garnered widespread industry approval. Newmarket Handicap Day experienced forecasted temperatures of 39 degrees, prompting earlier starting times and the rescheduling of two races on the card to alternative days.
Similarly, Racing SA officials took proactive measures in response to forecasted temperatures of 40 degrees in South Australia on Saturday, opting to bring forward the Magic Millions meeting at Murray Bridge to avoid the hottest part of the day.
Additionally, stewards enacted a Level 2 Hot Weather Policy for Morphettville’s Adelaide Cup Day due to forecasted high temperatures of 36 degrees. Measures implemented included revised transport and arrival times for horses and the addition of a third veterinary resource.
These changes, particularly the revised transport and arrival times, are crucial in mitigating prolonged heat exposure for horses and Ballarat based trainer Henry Dwyer couldn’t agree more.
“I don't think the heat affects them (horses) that much, it’s more so travelling in the heat because it just prolongs the day and prolongs the (exposure to the) heat. If the meeting is at home or somewhere close, we'll be happy to run in the heat. But in general, if we have to travel, then we probably don't.”
“... it’s more so travelling (not racing) in the heat because it just prolongs the day and prolongs the (exposure to the) heat.” - Henry Dwyer
Backing his word, Dwyer illustrated his point by sharing his decision to delay sending sprinting mare Prairie Flower (Star Turn) to Murray Bridge's scorching Magic Millions raceday and opting instead to run her at Morphettville on Adelaide Cup Day. It was a decision that proved fruitful given the 4-year-old mare took out the final event on the card.
Lindsay Park Racing’s co-trainer JD Hayes also commended the adjustments made to race scheduling on warmer days. With two runners on Newmarket Stakes Day, Hayes acknowledged that while the horses managed the conditions adequately, the alterations to start times serve a dual purpose of enhancing the industry's social perception.
“To a certain degree, they (the horses) can cop it. But if we're looking to do the right thing in the view of the community, it's always a good thing.”
Early decisions and strong communication are the key
Victorian Jockey Club CEO Matthew Hyland is a strong advocate for altering start times to avoid racing in the hottest part of extreme temperature days.
“I think all the decisions that have been made recently by Racing Victoria have been really sensible decisions. Obviously, turnover is key to our industry, and obviously the industry will take a hit, but we're still able to run those meetings. What we don't want is to get into a situation where we can't get those meetings run”.
Matthew Hyland | Image courtesy of the Victorian Jockeys Association
Although scheduling races around the hottest part of the day may impact betting turnover, it remains the most effective approach from both a social and equine welfare standpoint.
“You're not going to take your dog for a run on a 40-degree day in that extreme temperature. You're taking that dog for a run in the morning. So from the social perspective, the perception from people is, why would you run around a circle in extreme conditions,” said Hyland.
Speaking on behalf of the Victorian riding group, Hyland noted common sense is always the best approach. “What I would say is that if you ask the group, they'd be far happier working between 10.30am and 1.30pm on extreme days, as opposed to working in those extreme air conditions. That's just common sense.
“What I would say is that if you ask the (Victorian riding) group, they'd be far happier working between 10.30am and 1.30pm on extreme days, as opposed to working in those extreme air conditions. That's just common sense.” - Matthew Hyland
“They (authorities) have generally got a good idea within 48 hours of what's going to happen? They can't always get it right, but it's good when they're proactive and they make a decision ahead of time because on the day you can’t really plan when you get a few hours’ notice,” said Hyland.
Technology solutions on the horizon
While advancements in technology for thermoregulation monitoring show promise, the most effective methods for safeguarding horses from heat stress often revolve around practical, common sense approaches. Scheduling racing to avoid the hottest parts of the day remains as the industry’s best solution.
“I always start by saying the best way to deal with this is avoidance. If you can run your competition avoiding the worst conditions, then that's the best outcome,” said Dr Merlin when speaking about mitigation of heat stress in horses.
In addition to avoiding the warmest periods, Dr. Marlin noted walking horses immediately post competition has been implemented successfully in Olympic eventing disciplines. “Horses shouldn’t stand still. If they are showing signs of being ataxic, they should continue to be walked whilst being cooled at the same time”.
“Horses shouldn’t stand still. If they are showing signs of being ataxic, they should continue to be walked whilst being cooled at the same time”. - Dr David Marlin
Mitigating the effects of heat stress can start long before the peak of the heat. Dr. Marlin suggests mimicking raceday conditions during training having a positive influence on acclimatisation.
“A lot of the problems that occur potentially is that we still see riders who are training their horses at 5, 6am in the morning and then competing in the middle of the day.”
While adjusting the timing of horse training sessions later into the day might pose practical challenges for many trainers, incorporating treadmill sessions during the afternoon could enhance the horse's ability to tolerate warmer conditions.
Advancements in technology such as Biotherm microchips have the potential to take temperature readings, as well as store each horse's unique identification number.
Dr Osborne is complimentary of the technology highlighting that, “they allow you to measure the horse's rectal temperature or core body temperature non-invasively (and that) would have a very useful role to play here in monitoring a horse who is at risk of heat stress or is actually undergoing an episode.”
Prioritising the comfort and well-being of horses is paramount in managing the effects of heat stress. While our PRAs are responsible for monitoring and scheduling racing around the hottest periods of the day, our trainers and horsemen are also responsible for mitigating the effects of heat stress long before the race takes place.
From acclimatising horses in training to avoiding travelling horses in the warmest parts of the day, trainers can play an integral role in preventing heat stress in equine athletes. At the end of the day, optimising the welfare of the horse is in our best interests and a common sense approach to protecting our horses will take us a long way.
