To humans, wood chewing by horses might feel like this cartoon depicts – as part of a conspiracy to annoy humans. But it’s not. Honest.
So why do horses chew wood? For a number of reasons. Part of the horse’s natural diet includes browsing and nibbling on bark and small branches that provide woody fiber. When horses are denied the ability to perform this behavior, they may resort to chewing on fence boards, barn siding, or anything else they can reach – particularly in the wet winter months. Horses who chew wood may also do so when they aren’t getting an adequate amount of daily fiber. The fiber content of hay and pasture can vary, and if the forage the horses are eating doesn’t have enough fiber to satisfy the horse’s needs, he may resort to chewing wood.
Horses that are fed a diet high in concentrates, or those who eat pelleted foods (such as hay pellets or cubes) to replace long-stemmed hay or pasture are more likely to chew wood, as are those who are fed set hay ‘meals’ (i.e. 2-3 times a day). Horses have evolved to eat for 14-20 hours a day, and their GI tract is designed to be continuously processing forage. Set meals and pelleted foods don’t satisfy the horse’s physical and psychological need to select, chew (over 50,000 times a day), and process forage, and can lead to wood chewing. Unlike pica (ingesting non-food items such as soil or clay) it is not believed that wood-chewing is a sign of a nutrient deficiency – contrary to what some supplement manufacturers may tell you.
Horses may also chew wood when they are under-stimulated or under-exercised. Being confined to a stall or small paddock with nothing to do doesn’t allow the horse to fulfill many of his natural behaviors. Being ‘turned out’ for the day in a small paddock does not allow the horse to fulfill his need to move about, almost continuously. Turn out should allow the horse to freely walk, trot, canter gallop, buck, fart, roll, and play with other horses. Riding and schooling the horse may allow him relatively brief, controlled exercise, but horses sill need to be able to choose how and when they wish to move in order to fulfill their behavioral needs.
So, what can you do to reduce or stop wood chewing in your horse?
McGreevy, P, Equine Behavior: A guide for veterinarians and equine scientists Saunders:Edinburgh p 195, 200-201,, 2004.
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Houpt KA, Perry PJ,, Hintz HF, Houpt TU: Effect of meal frequency on fluid balance and behavior of ponies. Physiol Behav 42:401–407, 1988.
Jackson SA, Rich UA, Ralston SL: Feeding behavior and feed efficiency in groups of horses as a function of feeding frequency and use of alfalfa hay cubes. J Anim Sci 59 (Suppl 1):152-153, 1984.
Salter UE, Hudson RJ: Feeding ecology of feral horses in western Alberta. J Range Manag 32:221-225, 1979.
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Lauren Fraser, CHBC offers relationship-based horse training that blends the art of horsemanship with behavioral science and the practical application of learning theory. She provides horsemanship coaching, behavioral consultations, solutions to problem behaviors, foundation training, clinics, and educational presentations.
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True narcolepsy is rare in horses, but sleep deprivation is not.
This video shows an older mare who is sleep deprived, falling into REM sleep while standing. Horses must lay down to achieve REM sleep, and when deprived from doing so it may manifest as the behaviors you see here. Sleep deprivation is harmful to the health of all animals, so it is very important that your horse has the ability to lay down each day, and feels safe to do so.
Horses won't lay down to sleep for a number of reasons such as pain, lack of suitable resting sites, or when they don't feel safe to lay down. It's reported that two factors resulted in this mare not laying down to sleep - the arrival of a new horse, and undiagnosed arthritis pain ... See MoreSee Less
Sleep Disorder Case : Horses require 30mins/day REM sleep. Siri is a 22 year old Arab X mare. Last summer after a new, dominant horse was introduced to the herd, she lost weight and was seen to have frequent episodes of partial collapse, once falling onto her side. The episodes resolved, but a couple of weeks ago the same behaviour was observed again and New Forest Equine Vets were called in to investigate. Collapse in horses is fortunately uncommon, but when it does occur can obviously be hazardous to both horse and handlers. Three types of 'collapsing' are seen in horses; seizures, syncope (fainting) and sleep disorders. Siri underwent a very thorough clinical examination including neurological and musculoskeletal assessments, and had a range of blood tests performed. The most significant findings were; The original association of the behaviour with the arrival of a new field-mate. A low grade right hind lameness, with severe persistent right hind pain with flexion tests. The gradual lowering of the head, before the front legs buckle. We also found a cardiac arrhythmia; Siri has a second degree AV block, but this is a normal finding in horses and would not cause fainting. Siri's condition is a Sleep Disorder. True narcolepsy can occur in horses, and is usually associated with events like grooming or saddling. Siri is most likely suffering from sleep deprivation. Horses require 30 minutes of REM sleep per day and although they can doze standing up, they need to lie down for REM sleep. We expect that when the new dominant herd-mate arrived, Siri was not comfortable to lie down in the field with him. Now she has lameness and finds it painful to flex her right hindlimb, which is likely to be preventing her from wanting to lie down to sleep. She is currently on a bute (pain relief) trial, and her owner has made her a lovely deep stable bed that she is coming into daily to encourage her to lie down – so far, no further collapsing episodes have been seen. A very interesting case and a good reminder of how important it is for horses to feel comfortable, physically and psychologically in their herd/environment, so that they don't miss out on their REM sleep.
3 days ago ·