Sleep behavior of horses
The sleeping behavior of domestic horses is very complex and has to be considered specifically for each individual. It is important for horses that they are always ready to flee. Horses living in the wild often prefer elevated berths with good all-round visibility in order to be able to spot enemies at an early stage. As a further safety measure, all horses in a herd never lay down at the same time, at least one horse stops in order to be able to quickly warn the others in case of danger. In between, horses sleep for several short periods of sleep, which can last from a few minutes to an hour. Horses are awake approx. 75% of the day, 8% of the day they doze, 13% they spend in the deep sleep phase (SWS sleep), 4% they sleep in dream sleep or REM sleep.
Sleep phases
Sleeping in horses can be divided into three different phases : dozing, SWS sleep and REM sleep.
Doze off
The dozing in the horse can be assigned to the SWS sleep. It is an intermediate phase between being awake and sleeping. Horses doze for about two hours a day. They spend most of it standing, but also lying down. The muscles are hardly tense. This way the horse can relax without actually having to sleep.
SWS sleep
SWS sleep means slow wave sleep, it is also known as deep sleep. During SWS sleep, the respiratory and heart rates slow down and the brain becomes inactive. Sometimes you can see muscle movements. Many horses spend this sleep phase lying down on their chest, but it can also be achieved while standing. Although the brain is inactive, horses are aware of everything in this phase and are ready to react immediately if danger threatens.
REM sleep
REM sleep means rapid eye movement sleep. With REM sleep, breathing and heart rate are reduced even further than in SWS sleep. The brain is very active during this sleep phase, which can be seen in the twitching eyes. Horses always go into SWS sleep and then into REM sleep. Horses can only reach the REM sleep phase while lying on their side and it is extremely important for muscle recovery.
Sleep behavior of adult horses
Adult horses rest an average of seven hours a day. They spend about three hours sleeping and more than three hours dozing. If the feed quality and quantity are poor, the resting phase can be shorter, if the feed quality is good, longer.
Horses lay down for deep sleep. If they are not left alone by others and are stressed or ill, they no longer lie down and can therefore no longer enter the deep sleep phase.
Should this happen, horses suffer a significant lack of sleep, which can lead to a narcoleptic disorder (for example falling over from a standing position due to muscle fatigue as a symptom of overtiredness). If care is taken to separate these horses for sleeping, the symptoms of narcoleptic disorder can subside.
Sleep behavior of foals and young horses
Foals sleep much more than adult horses. You need several deep sleep phases during the day. Especially in the first few days, foals get tired quickly and sleep a lot, always at short intervals throughout the day. During the day they usually spend up to 3.5 hours dozing during this time, horses usually lie on their chest. At night, foals only sleep a few minutes up to six times. The longest sleep cycle lasts up to 15 minutes and you spend it lying on your side. Foals need a dry, warm and clean surface in order to sleep, otherwise they cannot rest properly.
Fillies and colts differ in their lying behavior, so fillies lie on their side almost twice as long as colts.
Sleep behavior of old horses
Old horses often do not lie down anymore because getting up causes them pain or is too strenuous. Therefore, with old horses, care should be taken to ensure that they get enough rest, that they have enough space and that the floor is comfortable to lie on so that they do not get any sleep disturbances.
Sleeping positions
Horses can sleep in three different positions: standing, lying on their chest or lying on their side.
Horses don't always lie down. If the box is too small or not mucked up often enough, horses stop to sleep. Psychological causes such as fear or nervousness can also be reasons for this. It is therefore important that horses always have a clean, dry place to sleep and that they are given enough time to rest.
If all of this is given, there may be other reasons that the horse does not want to lie down. One reason may be that the horse has difficulty getting up again, this often affects horses that are old or have spars.
Sleep standing up
When horses sleep standing up, they lower their heads, close their eyes half or fully, and hang their lower lips. In addition, horses never put weight on all four legs during this phase. They always relieve one of their hind legs, which they change every 4 to 5 minutes. In this posture, horses can escape at any time and do not have to get up beforehand. So horses are always mindful and can still explore their surroundings with their ears.
Sleep on your chest
The horse lies down, pulling the front and rear legs under the body. The horse keeps its head upright while it usually rests its mouth on the ground. Keep your ears moving while lying down to observe your surroundings.
Sleep on your side
The horse lies down on its chest. It then lies down on one side of the body and extends all four legs. In this position the horse gives up its complete vision and must feel absolutely safe.
Individual evidence
- ↑ a b c d e f g h i j k Claudia Fader: Elimination and resting behavior of horses in open stalls and boxes . University library of the Technical University of Munich, 2002 ( tum.de [accessed on November 15, 2018] dissertation).
- ↑ a b c d e f g h i j k l Fuchs, Christine: Narcolepsy or REM sleep deprivation ?: 24-hour monitoring and polysomnographic measurements in adult “narcoleptic” horses. February 11, 2017, accessed November 15, 2018 (dissertation).