It's mid-July, wildfires are consuming acreage in the West, and temperatures are higher than usual and climbing in many areas. HIt's orses and other equines will be facing temperatures that can lead to heat stroke, heat exhaustion, and possible fatalities.
To help horse owners with information relative to the heat in many areas, weather sources, universities and livestock oriented extension services have developed heat indexes that show alerts when temperatures threat the health and safety of horses and other animals. Check to see if such an index exists for your area.
When air temperatures are hot, heat production can increase as much as 50% during intense exercise of horse athletes. The horse sweats to move more blood to the capillaries under the skin and breathing rate increases to release built-up heat. The horse's system may be unable to keep up with the mounting heat to the point that it becomes dehydrated.
Profuse sweating, rapid breathing, and rapid heart rate are indications that the horse is stressed and needs to be moved to a shady area, allowed to cool down, and given sips of water to combat dehydration.
If the horse cannot be cooled down, the nervous and muscular systems will cease to function normally. When these systems stop functioning, heat stroke is inevitable unless measures are taken to cool the horse down and replace fluids lost because of sweating. If heat stroke is suspected, the veterinarian should be called immediately and steps taken to cool both the horse and the environment.
Symptoms of heatstroke in equines include:
- Profuse sweating
- Rapid breathing
- Rapid heart rate
- Hot, dry skin
- High rectal temperature of over 104 degrees
- Sunken eyes and dull expression
- Loss of skin elasticity
- Cessation of urination
- Convulsions and possible collapse if preventative measures are not taken.
A combination of too much exercise and hot, humid weather are the common causes of heat stroke. When the sum of the ambient temperature in degrees Fahrenheit and the relative humidity is around 150, caution should be used in exercising the horse so heat build-up doesn't become critical.
Horses that are affected by anhydrosis (absence of sweating) are extremely susceptible to heat stroke, and special care should be taken with them since the most important mechanism for heat dissipation in horses is evaporation through sweat. In addition, horses that are unfit or overweight are more susceptible to heat stroke and exhaustion than more fit and lean horses.
Of paramount importance is making sure that your horse and other animals have an ample supply of fresh, clean water within easy reach. Check the water supply daily and make sure that the water does not become contaminated with bird droppings, algae or other contaminants. You may want to supply electrolytes along with fresh, cool water to help keep your horse's system in balance.
If your horse becomes overheated because of high temperatures, use shade, cool water, breezes, or fans to cool the horse. If possible, stand your horse in a pond or stream. Sponging or spraying the large blood vessels along the inside of the legs and belly can be helpful in cooling your horse.
Heat stroke can happen to horses whether they are working hard, standing in stuffy stables, or traveling in trailers. Call a vet and take immediate action if your horse exhibits any symptoms of heat stress.
Edited article first published July 2012