NORMAN — Oklahoma temperatures will be soaring upward soon, and that can be quite a shock for horses, especially given how Old Man Winter hung on until recent weeks.
“The sudden shift from cooler-than-normal temperatures to those associated with summer underscores the need for horse owners to monitor their animals closely,” said Heath Herje, ag educator for Oklahoma State University Extension in Norman.
During exercise, there is a significant increase in the amount of heat produced by working muscles. Heat production estimates can increase as much as 50 percent during periods of intense exercise as compared with heat production when the horse is at rest.
In response, a horse increases its sweating rate, moves more blood to the capillaries under the skin and increases its rate of breathing in an effort to release this buildup of heat.
“Heat stress from exercise can result when the environmental temperature is high,” Herje said. “Commonly observed signs of heat stress are profuse sweating, rapid breathing rate and rapid heart rate.”
Some horses are anhidrotic, meaning they have little or no ability to produce sweat. Since heat loss is mainly dependent on convection (wind) and evaporation (sweating), anhidrotic horses are prime candidates for heat stress.
“Owners who suspect a horse to be anhidrotic should consult with their veterinarian, as diagnostic tests exist that can be conducted,” said Dave Freeman, Oklahoma State University Extension equine specialist.
Early stages of heat stress can advance into more critical symptoms associated with heat stroke. Symptoms include skin that is dry and hot, pulse and respiratory rates much higher than normal and unusually high rectal temperatures.
“Horses that exhibit these symptoms require immediate attention,” Freeman said.
Freeman advises that the horse be moved to a shady area with fans or wind to provide ventilation. Cool water should be sprayed on the horse’s body and legs to help the evaporation process.