Q: My horse chews wood. People at the barn say it is due to a nutritional deficiency, but I’m not sure what that deficiency is?
A: Many horses like to chew or eat wood in their stable, or nibble on paddock fencing. For owners, this can be frustrating, but chewing on wood, twigs and bark is actually totally natural behaviour for horses. If we don’t provide horses with appropriate places to carry out this wood chewing, then they may start to chew things that we would prefer them not to! There are several different tree species that horses particularly enjoy chewing the bark of. Favourites include oak (ensuring that there are no acorns), poplar, ash and apple. Many horses also enjoy chewing willow, but this must be monitored, as the bark contains salicin, which has pain-relieving properties and is similar to the main ingredient in aspirin.
You therefore don’t need to panic that your horse has a nutritional deficiency, but rather just make sure he has access to some wood he can safely and happily chew – that isn’t holding stable or paddock together!
NOTE: It is important to differentiate between wood chewing and wind sucking however. Wind sucking, which is also known as crib biting, is a stereotypic behaviour where a horse grips onto a surface and sucks air in, often making a strange noise. If your horse is wind sucking/crib biting, he is displaying a stereotypic behaviour and this is of concern, especially if it is new. We would advise in these instances that you speak to your vet, and also that you look at making some lifestyle changes for your horse, such as more paddock time or more time spent with other horses.