-- by Vikki Fowler, veterinary equine dentist
Wind sucking is a habit when the horse arches the neck and sucks in air. Crib biting, aka cribbing, is wind sucking whilst holding on to a fixed object. A more scientific term is "oral stereotypic behaviour". I will use the term crib biting in this article as an all-encompassing term as this is most commonly seen.
- Paleontological evidence suggests that horses have been crib-biting since their domestication (6,000 BC) whilst tethered.
- Cribbers show increased stress sensitivity and decreased behavioural flexibility, they struggle to cope with stress. Crib biting has been shown to reduce the horses stress level. It appears the behaviour is a coping mechanism that allows them to deal with external stresses. Preventing the behaviour, particularly physically (collars, bars, foul tasting pastes etc) without addressing the underlying causes is of great concern to the horse's welfare. These horses NEED to crib, preventing them doing so is cruel, instead try to reduce their desire to.
- Genetic predisposition - Although the gene has not been found yet, stereotypies are widely considered to not be learned behaviour but rather an actual physical difference within the brain passed on from one or both of the horses parents and brought on by environmental stresses.
- Studies have shown links between crib biting and reduced blood selenium levels (potentially a lack of multiple antioxidants) which is also seen commonly in human schizophrenic patients.
- Research is currently looking into the differences between normal horses and cribbers in the striatum (an area within the brain that deals with habit forming and the body’s reward centre), early studies show remarkable similarities to people with autism.
Quick Learners
- Crib biters are very quick to form new habits and very slow to unlearn behaviours. This can be used to the riders/handlers advantage if trained carefully to ensure the horse never has a negative experience. Many very highly successful horses are crib biters due to their quick learning. Cribbers are not cognitively impaired unless the behaviour is prevented, then horses show poor judgement and choices.
- Environments where highly motivated, goal-directed behaviours are encouraged could reduce the development of crib biting. Simply put, positive reenforcement with a good deal of activity and mental stimulation when a horse is young will reduce the chances of them becoming a crib biter.
- Crib biters have been shown to have an increased sensitivity to touch, this may go some way towards explaining why these horses find the action of cribbing satisfying compared to a normal horse.
Movement and Social Contact are Key
- Cribbing increases the chances of medical (gaseous) and surgical (epiploic foramen entrapment) colic but it is better to ensure the horse has plenty of movement/turn out and exercise rather than physically stopping the horse from cribbing.
- Studies have clearly shown cribbing does not create saliva to buffer increased acid in the stomach. However studies have shown a higher-than-normal release of acid in the presence of a high cereal concentrate feed in crib biters which could then lead to stomach ulcers. As I have already mentioned, cribbers are also usually highly anxious and stressed animals, and stress has been shown to increase the likelihood of stomach ulcers. So cribbers should be managed as an ulcer-prone horse.
- Plenty of social contact time has been shown to decrease stress and stereotypic behaviours. Both visual and tactile contact reduced the amount of time spent cribbing. Simply put, horses need to be able to see and touch other horses almost constantly to reduce the cribbing behaviour.
Cribbing and Dental Care
- Cribbing on metal surfaces in particular, but also wood surfaces to a lesser degree, is very bad for incisor wear. Horses have a finite length of tooth, once it runs out, that’s it. If the wear is particularly quick, the sensitive pulps of the teeth could be exposed resulting in infection and the need for surgical extraction. Horses need their front teeth to pick hay from haynets, bite grass, pick up food etc, whilst they can cope without front teeth when necessary, it is advisable to avoid this tooth wear.
How Can You Help?
So, how can you help your cribbing/wind sucking horse?
1 - Increase the time the horse spends eating, ensure they always have forage in front of them. Always.
2 - diets suitable for laminitics or ulcer-prone horses are also suitable for cribbers. This means no cereals and no molasses (this counts out many mixes and cubes unless specified cereal and molasses free).
3 - Alfalfa and unmolassed sugarbeet are very good at neutralising stomach acid and reducing the chance of ulcers forming and reducing the horses desire to crib after their feed.
4 - Antacid supplementation may be beneficial to prevent ulcers.
5 - Consider Selenium or other antioxidant supplementation. But take care as selenium is toxic when given in excess. Ideally discuss your horses diet with a nutritionalist or your vet.
6 - Avoid all sugary treats, polos, likits, horslyx etc as these increase the desire to crib.
7 - Provide social contact, neighbouring horses the horse can see and touch, windows, mirrors will all reduce the horses desire to crib.
8 - Daily turnout. As well as the mental enrichment this provides, the movement decreases the chances of colic significantly. This is true for every horse but particularly cribbers that suffer from gas build up. Ideally a minimum of 4 hours every day all year round. Tethering and stalling are not suitable for cribbers.
9 - Mental enrichment, toys, boredom breakers, clicker training, ridden work, Liberty work, anything to keep the horses mind active and provide reward based learning.
10 - Give the horse something soft to crib on to prevent excessive tooth wear. For example old carpet, rubber matting over the door, soft rope. It will need replacing regularly but the horses teeth can not be replaced.
Crib biters can live a long and healthy life, they are often wonderfully talented ridden horses with the right rider/owner that takes the time to understand their natures and quirks.
-- by Vikki Fowler, veterinary equine dentist
Related Links
Why do Horses Need their Teeth Tending To? What about Those in the Wild?
From the Horse’s Mouth... Actually the Horse’s Tongue
A Bit is Only as Harsh as the Hands that Hold It