Year round requirement | While dehydration normally occurs in summer, horses can also lack sufficient water in winter
Many people recognize the need to make sure animals get enough water during summer. The rodeo and show season highlights that need for horses.
Julia Montgomery, assistant professor in large animal clinical sciences at the Western College of Veterinary Medicine in Saskatoon, said horse owners can use two simple tests, the capillary refill and the skin tent, to see if their horses are dehydrated.
“[For the capillary refill] you lift the upper lip and you look at the horse’s gums. You can pinch it with a finger and it will go white and we count how long it would take for the colour to come back. It should be less or equal to two seconds,” said Montgomery.
If the refill time is prolonged, it means the animal’s body may be prioritizing major organs, such as the brain and kidneys, with available water. In that case, more water should be provided.
In the skin pinch or tent test, the skin on the neck is pinched and twisted to make a tent. The skin should snap back to normal within about a second. If it doesn’t, it is a sign of dehydration.
In a clinic setting, a veterinarian can conduct a blood test to determine the number of red blood cells, which also can determine dehydration. Vets use percentage dehydration when they assess animals. At be-tween five and 12 percent dehydration, animals will show clinical signs with the capillary refill and skin pinch.
“If we say it’s 10 percent dehydrated and it weighs 500 kilograms, then what we need to replace is 50 litres. So we would replace half of that fairly quickly and the other half over about 12 hours,” she said.
Horses can also become dehydrated in winter if freezing temperatures reduce their access to water.
“Snow is not an adequate water source. Horses, in a pinch if they have to, eat snow, but they will never take in enough to make it an adequate water source.”
Montgomery encourages horse owners to check the Equine Code of Practice for more information. It is at www.nfacc.ca/codes-of-practice/equine.