There has been a significant increase in research and resources devoted to sleep, or the lack of, in humans. However, horses sleep very differently to humans. Most people believe that horses just stand around and sleep. Horses can take short nag naps while standing up, like we do in front of the TV, as a sort of short sleep needed to avoid predators, when they were around. Horses sleep standing up using a method called reciprocal apparatus. When this is locked into place, the horse needs minimal muscle function to keep standing. Everything else can then relax.
For animals that sleep, and that’s just about all of them, rapid eye movement (REM) sleep is the key to good quality, restful sleep. Sleep research has pointed to the critical role REM sleep plays for all of these animals.
REM sleep allows our brain to process things we’ve learned during times of wakefulness and to declutter our brain. Horses need to have REM sleep every three days to keep physiologically and mentally healthy, which doesn’t happen when a horse naps standing up.
A lack of REM sleep has a similar effect on horses as it does on people. Horses lacking REM sleep become irritable, clumsy and generally not themselves. They may also fall asleep while standing up.
The problem You may notice your horse falling asleep standing up when you’re grooming them or any other activity when they are still, but it can happen anywhere, even when you’re riding them. In less obvious cases, horses can lower their neck, buckle at the knees or lean against fences or other objects. Affected horses can hit that wall of sleepiness and hit the ground very suddenly. In humans, this is a medical condition called narcolepsy. In horses, this is also a real medical condition, which occurs when the brain inappropriately triggers sleep. This occurs when horses are sleep-deprived. There is also a rare genetic condition of some miniature horses, which has the same effect. Narcolepsy can be challenging to diagnose and to treat, and there are currently no recognised criteria for definite diagnosis.
Cause and treatment The primary issue to consider in horses with this condition is pain in the back, neck or hip. Pain can disrupt the action of laying down, especially in older horses, which means they can’t comfortably get to sleep.
Consulting our team about investigating the source of any pain may involve a trial of a pain relief drug to help determine the cause of this lack of sleep. If this works, the improvement can be dramatic. Your horse is back to its normal temperament and no more falling asleep on the job.
Another possible cause can be the group of horses that your horse spends time with. Horses need to feel safe to sleep. Changes to their social interactions can cause a horse to feel less safe and be therefore less likely to sleep effectively (reach REM sleep). This can happen for horses transported into a new social group.
Improving quality of life for these horses needs a lot of trial and error. Assessing your horse’s place in the social hierarchy may allow you to place your horse in a group where they can feel safer. This could be accompanied by medication to manage anxiety and make them sleep easier.
If you eliminate these two more common causes, it can sometimes lead to other physiological causes which are, sadly, more difficult to treat.
Contact our team if you have any concerns about your horse’s sleep. |