This blog post goal Is to take a quick look into the relationship between equine sleep patterns and welfare. I aim to offer insights to horse owners on how understanding and supporting natural sleep behaviors can enhance the welfare for our horses.
Have you ever considered how much sleep your horse is getting and how much they need? One study reported that only 50% of horse owners thought their horse slept more or equal to four hours a day (Greening, 2022). It also showed that 17% were unsure of their horses sleep patterns, and 29% never even considered their horses sleep (Greening, 2022). This study also revealed that 55% of owners did not chalk up their horses' lethargy to lack of sleep (Greening, 2022). These statistics show that sleep is often not considered a part of horse welfare, despite emerging research indicating the great importance it has.
What is sleep?
Sleep is called a maintenance behaviour, as it is essential for physiological and cognitive function (Kelemen, 2021). Sleep involves a loss of unconsciousness or comparable inactivity for a distinct set of time (Kelemen, 2021).
Types of Equine Sleep:
A horse sleeps in 5-7 polyphasic episodes, meaning that sleep occurs multiple times throughout a twenty-four hour time-span (Kelemen, 2021). Humans are monophasic sleepers, meaning they sleep only at night in one episode (Greening, 2022). Horses need approximately 4-5 hours of sleep, which is divided into NREM and REM sleep (Greening, 2022).
Standing Sleep: Also known as NREM sleep: Horses primarily sleep in this stage (Greening, 2022). Horses are prey animals, so this stage of sleep is vital for responding to potential threats quickly (Greening, 2022). Horses are able to sleep standing by a locking mechanism that occurs in their leg joints, that prevents them from falling over (Greening, 2022).
Recumbent Sleep: Horses must be recumbent, or lay down in order to enter into REM (Rapid Eye Movement) sleep (Kelemen, 2021). Horses need about 30-45 minutes of REM sleep per 24 hours and this is the most vital part of a horse's sleep (Kelemen, 2021). This sleeping state is important for horses' physical and mental wellbeing (Kelemen, 2021).
Factors that Influence Sleep:
Below is a list of the main contributing factors of reduced REM sleep. More research is emerging on other factors that can also affect sleep cycles, but for the purpose of keeping this more concise, only the main factors will be discussed.
Allowance of Space: Research has shown that if there is no available space to lay down, horses lack REM sleep (Kelemen, 2021).
Bedding: Studies have shown that a lack of proper bedding and the softness of bedding can affect sleep (Kelemen, 2021).
Herd Dynamics: Horses that are not in a herd or near any horses can feel unsafe. Horses in herds naturally take turns sleeping in order to feel protected. Therefore, REM sleeping patterns can be disrupted in horses that lack a herd dynamic and are alone.
Lighting and Loud Noise: Nighttime checks and noises were noted to affect REM sleep cycle as it may affect melatonin cycles (Kelemen, 2021). Although, consistent gentle noise such as music at night showed to improve REM cycle sleep (Kelemen, 2021).
Health: Research has shown that unmanaged arthritis, musculoskeletal disease and gastric ulcers decreased laying time as well, as the horse often was in pain in getting up. Controlling these issues with pain medications increased laying down time.
Psychological Stress: Horses under stress, such as feeling uncomfortable or changes in their environment have shown to have reduced sleeping states.
REM Deficiency
REM deficiencies have shown to cause a wide-array of issues. Stereotypies, which are unwanted behaviours understood to primarily form due to stress, were increased with a lack of REM sleep (Kelemen, 2021). Researchers initially wondered if stress worsened sleeping states or if a lack of sleeping states worsened stress (Greening, 2022). Current research has shown that stress causes a lack of sleep, which in turn a lack of sleep worsens stress in horses due to fatigue (Greening, 2022). Stress can cause an array of behavioural problems in horses that can make training and everyday handling difficult and even dangerous (Greening, 2022)/ A lack of REM sleep can also cause horses to collapse onto their front fetlocks, causing painful sores that can occur (Kelemen, 2021). Therefore, REM sleep has shown to be imperative for both psychological and physical aspects of horse welfare.
Importance of Understanding Sleep for Equine Welfare
Research suggests that there is a strong correlation between sleep quality and overall welfare in horses. A deficiency in sleep can cause:
Behavioral Issues: Such as, agitation, anxiety, and reduced performance.
Mental Health: Can impact cognitive function and emotional well-being.
Physical Health: Collapsing due to lack of sleep can cause painful sores on the front fetlocks.
Conclusion
Understanding the connection between equine sleep patterns and overall welfare is essential for responsible horse husbandry. Promoting natural sleep behaviors and ensuring optimal sleep conditions can allow horse owners and caretakers to enhance the health and happiness of their horses. Further research into equine sleep physiology should continue in order for horse owners to gain new information that can lead us to continually improve standards of care and management practices in the future. To conclude, prioritizing sleep as an important component of equine welfare promotes respecting the natural behaviors and biological needs of horses, which can provide a harmonious relationship between horse owners and their equine partners.
References:
Kelemen, Z. et al. (2021) Recumbency as an Equine Welfare Indicator in Geriatric Horses and Horses with Chronic Orthopaedic Disease. Animals (Basel). [Online] 11 (11), 3189-.
Greening, L., McBride, S., (2022). A Review of Equine Sleep: Imp lications For Equine Welfare. Frontiers in Veterinary Science. [Online]. (9). 1-22. Doi: 10.3389/fvets.2022.916737
Comments