Last Updated on February 19, 2022 by Allison Price
Although horses can and do stand up sleeping, all horses need to lie down at some point in order to have a complete sleep cycle and avoid sleep deprivation. The time and place that horses sleep can have an impact on how they are managed.
While it is still not known what horses need to sleep, there are some facts that have been gleaned from different research groups:
- Horses spend the majority of their time eating, resting, and sleeping.
- About 5-7 hours per day are dedicated to resting, with actual sleep occurring usually after midnight in the darkness hours.
- Horses can sleep while standing, and some types of sleep (e.g. slow-wave sleep) can be achieved while they rest. However, horses cannot enter the rapid eye movement phase (REM) without being in recumbency. This is due to muscle tone loss during this phase.
- Horses need at least 30 minutes of recumbency per hour to satisfy their REM sleep requirements.
Horses may not be able to lie down due to poor environmental conditions, such as lack of space or weather, social anxiety (low pecking order), or physical complaints (musculoskeletal pain). These horses may experience excessive drowsiness and REM deficiency. Horses with REM problems may fall asleep while standing, then collapse and wake up suddenly.
One research group measured recumbency in horses without and with access to soft, bedding areas to better understand the factors that influence horses’ ability to lie down. Horses who did not have a bed area (they only had hard black rubber mats) slept less than 30 minutes REM. Horses spent more time lying down as the area was suitable for recumbency grew. Low-ranking horses could lay down as often as higher-ranking horses if large areas of bedding were available. Low-ranking horses were forced to end their lying sessions when their bedded area was smaller.
Ensuring sufficient space for horses to rest comfortably for at least 30 mins every day, and addressing underlying medical reasons for reduced recumbency (such as osteoarthritis) improves the quality life of group-managed horses. This also minimizes welfare problems.
Joint supplements that include chondroitin, glucosamine, hyaluronic and omega-3 fatty acid support healthy joints. These products lubricate joints and help reduce discomfort and inflammation associated with OA. This could potentially make it easier for horses become recumbent after REM sleep,” said Kathleen Crandell Ph.D., a nutritionist at Kentucky Equine Research.
Horses that are overweight may have difficulty lying down or rising from a sitting position, which could limit REM sleep. Make sure your horses are in good health.