IS YOUR HORSE GETTING ENOUGH SLEEP?
We all understand the importance of getting a good night’s sleep for ourselves, but how do we know if our horses are getting enough — and what are the implications if they aren’t? Vet Mike Hewetson investigates
Spot the signs and the health effects
ASTUDY DURING THE 1980s revealed that horses need two to three hours sleep every day and, of that, they need at least half-an-hour to an hour’s worth of rapid eye movement (REM) sleep, which can only take place when the horse is lying down.
So what happens if your horse isn’t getting enough sleep and is therefore sleep deprived? The main issue we see with horses who suffer from sleep deprivation is that they demonstrate characteristic clinical signs which for many years were incorrectly identified as narcolepsy — a horse falling asleep on their feet.
Narcolepsy is a clinical disease that causes horses to collapse into a cataleptic state in which they are relaxed but collapsed on the ground. Sleep deprivation collapse in horses is a little different in that they will be standing and their heads will slowly drop, as if they have been sedated, and they get to a point where their forelimbs begin to buckle. It’s usually at this point, just before their knees hit the ground, that they wake themselves up out of the state, like someone falling asleep at the wheel when driving.
When they’re really tired, they actually collapse into REM sleep, and that’s when they can seriously injure themselves.
This is the description that vets often receive when they’re called out to horses who have strange, unexplained injuries to their knees, lower limbs and head.
These signs are often related to sleep deprivation.