Does your horse, or a horse you know have a range of weird symptoms? Unexplained abrasions on the face, fetlocks, knees and hocks? Hypervigilance? Bowing, stumbling, or partial collapse? 'Laziness', loss of appetite, general grumpiness? Consider whether this horse is getting enough sleep.
Sleep Deprivation in Horses: A Hidden Threat Sleep is a fundamental requirement for all living beings. It plays a crucial role in cognitive functions, particularly memory consolidation. In horses, sleep deprivation can lead to serious health issues. Understanding Sleep in Horses Horses are polyphasic sleepers, meaning they have multiple sleep periods throughout a 24-hour cycle. They require between 3 and 5 hours of sleep per day, primarily during the night. The most significant phases of slow-wave and paradoxical sleep occur between midnight and 4 am. Unlike humans, horses must lie down to enter the paradoxical (or REM) phase of sleep. If a horse is unable or unwilling to lie down, it may suffer from sleep deprivation. I believed sleep deprivation is frequently overlooked. We ask a lot from them. We expect them to be athletes. We put them in situations without the forewarning that we have about where we are going, what we are doing and for how long. And for horses that have been sold, or moved multiple times - any trip on the float raises the possibility they may not be going home. The Consequences of Sleep Deprivation Sleep deprivation in horses can have severe consequences. There have been cases of spontaneous collapse linked to lack of sleep. This can be particularly dangerous if the horse is in motion or in an unsafe location at the time of collapse (like on your farrier). Management or physical problems can lead to sleep deprivation in horses. For example, a horse that is kept in a small stall without enough room to lie down comfortably may not get enough sleep. Similarly, a horse with joint pain, or other imbalances, may avoid lying down and thus miss out on crucial REM sleep. Horses kept alone may be reluctant to sleep without a 'sentinel horse' watching over them. Equally, a horse that's paddocked with a bully will avoid sleep. We see symptoms of sleep deprivation in horses taken away from home to compete. Away from their herd, in an unfamiliar environment, and often working harder than usual, sleep deprivation can reduce performance exactly when they need it most. Some horses are very resilient. Some horses may be extremely gymnastic or competitive, but still very emotional. The Importance of Proper Sleep Management It's important to understand the sleep requirements of your horse(s) and how to accommodate them at home and away. By ensuring that horses have a comfortable and safe place to lie down and rest, owners and caretakers can help prevent sleep deprivation and its associated risks. Horses also sleep standing up, and this is based on the 'stay apparatus'. Horses with a compromised stay apparatus will fall, which will wake them up. Here is another blog with more information about sleep deprivation and the stay apparatus. This blog also includes links to studies in equine sleep worth looking at. There are only limited studies about sleep deprivation in horses. Further research is needed in this area, as sleep deprivation is frequently misdiagnosed - often as something catastrophic (like 'wobbles' - a damaged spinal cord) that can end their career. As we continue to learn more about equine sleep patterns and their impact on health and wellbeing, we can develop better strategies for promoting optimal horse welfare. Have a look at the study below which reviews sleep deprivation in horses overall.
REVIEW article Front. Vet. Sci., 17 August 2022 Sec. Animal Behavior and Welfare Volume 9 - 2022 | https://doi.org/10.3389/fvets.2022.916737 A Review of Equine Sleep: Implications for Equine Welfare Linda Greening1* Sebastian McBride2