Heat Wave Preparedness

Weather extremes are a universal concern for horse owners. Any drastic temperature change can increase the risk of colic, while anhidrosis and overheating are particular concerns during hotter months. Miska Paget, DVM, owner of Williamson Valley Large Animal Veterinary Practice in Prescott, Arizona, explains hot-weather horse management and how owners can help keep their horses healthy and comfortable when scorching weather strikes.

Natural Cooling

During hot weather, horses will naturally seek shade. Paget says that if shade from trees isn’t already available in the horse’s environment, it is important to provide it in some other form. Barn air, she explains, can become stagnant and hot, so providing adequate ventilation, fans or even misters may be critical to keeping horses cool.

Drinking plenty of water, while important year-round, becomes even more critical during hot weather. Clean, free-choice water is generally most appealing to horses. While drinking water can help keep a horse cool, it also supports hydration and digestive health.

“What I like to do for my horses, for the ones that don’t drink well, is to make sure that they have access to electrolytes,” Paget says. “If they are not ones that like a salt block, then I give them an extra bucket of water with electrolytes in it.”

To avoid a possible electrolyte imbalance, she advises always offering a second bucket of plain water alongside the electrolyte-supplemented water.

Electrolytes, she explains, can also be offered as a top-dressing on feed. She says a tablespoon of table salt may also be effective, depending on the horse’s needs. Because electrolytes encourage horses to drink more, Paget says she is particularly mindful of providing them to horses that are prone to colic. Properly hydrated horses may be less likely to develop an impaction.

She also recommends adding water to hay pellets, cubes or feed to create a moist mash. In certain cases, mineral oil may be used under a veterinarian’s direction to help soften manure in a colic-prone horse.

Paget says electrolytes can be beneficial in situations beyond hot days at home. They may also be appropriate when horses are trailered or during periods of increased physical activity. While always important, hydration becomes even more critical when stress and exertion coincide with a heat wave because horses may sweat more and drink less.

Staying on Top of Preventive Care

According to Paget, horses kept current on veterinarian-recommended vaccination and deworming schedules may be better prepared to face a heat wave because they are generally healthier and better able to respond to weather-related stress.

However, she advises against administering vaccinations or dewormer during extreme heat.

“I don’t advise deworming during a heat wave or even vaccinating,” Paget says. “For example, if I have routine vaccinations scheduled during that time, I’ll bump them out to the next week. I don’t want the horse to develop a vaccine fever that can sometimes happen when it’s super hot outside. That’s tempting a problem.”

Adjusting Riding Schedules

Owners can further help their horses cope with a heat wave by adjusting when they ride.

“I think a good rule of thumb is to ride during the cooler times of the day before the sun is high,” Paget says.

Decreasing the intensity of a ride during hot weather is also advisable. Finally, if it is really hot and you are fortunate enough to have an arena, ride at night with the lights on.

Feeding Adjustments

Changes in exercise timing and intensity aren’t the only adjustments owners should consider. Paget also recommends evaluating how much feed is offered during periods of extreme heat.

“I tend to feed lightly during hot weather,” she says. “I don’t chunk a lot of feed at them just in case somebody isn’t drinking well. I don’t want them to have had a hot day and not have had a lot of water and then engorge on their hay ration and get colic.”

Feeding time also provides an opportunity to monitor a horse’s intake and output. Paget advises owners to track water consumption and urine and manure production whenever possible. Decreased output could signal a developing problem, as could manure balls that become smaller, drier or harder than usual. Recognizing these changes early may allow owners to address a problem before it worsens.

A Change in Location

Even if your area isn’t currently experiencing a heat wave, you may be planning to travel somewhere that is. Paget advises owners facing this situation to follow the same precautions they would take at home.

Horses have individual heat tolerances, and she recommends knowing your horse well enough to recognize whether it has acclimated or needs additional time to adjust.

Despite an owner’s precautions, a horse may still overheat during a heat wave. Signs of overheating include excessive sweating or a sudden lack of sweating; an elevated respiratory rate; flared nostrils; muscle tremors; abnormal behavior; and an unwillingness to move.

If this happens while you are working the horse, Paget says to stop immediately.

“Take your saddle off,” she says. “That will allow a lot of heat to leave the horse.”

She also says to offer the horse water and begin cooling it with a hose, concentrating on the legs, underbelly, underside of the neck, between the hind legs and beneath the tail. Move the horse into the shade or, if possible, in front of a fan.

Contacting a veterinarian for guidance or an evaluation is also appropriate, even if the horse appears to recover after cooling.

Final Advice

Heat waves can be stressful, and Paget offers this final advice for horse owners.

“I think it’s important to listen to your horse and to listen to your intuition if your horse isn’t acting right,” she says. “Don’t try to push through it. It’s OK to have a bonding day with your horse by bathing them, standing them in front of a fan, and braiding their manes. That’s nice for everybody.”