Choke (horse)

Choke is a condition in horses in which the esophagus is blocked, usually by food material. Although the horse is still able to breathe, it is unable to swallow, and may become severely dehydrated. A secondary condition, aspiration pneumonia, may also develop if food material and saliva accumulate in the pharynx, spilling into the trachea and into the lungs. Choke is one of the "top 10" emergencies received by equine veterinarians.

The condition is seen in other Equidae like mules and donkeys.

Chewing: Horses may develop choke if they do not chew their food properly. Therefore, horses with dental problems (e.g. acquired or congenital malocclusion, loose or missing teeth, or excessively sharp dental ridges) that do not allow them to completely grind their food are particularly at risk. In addition, horses that bolt their feed and do not take the time to chew properly are more likely to suffer from choke.

Dry Food: Dry foods may cause choke, especially if the horse does not have free access to water, or if the horse has other risk factors linked to choking. While pelleted or cubed feeds in general fall in this category, horse owners sometimes express particular concerns about beet pulp. However, while horses have choked on beet pulp, a university study did not document that beet pulp is a particular problem. It is believed that choke related to beet pulp is linked to the particle size and the horse's aggressive feeding behaviour, rather than the actual feed itself. Research suggests that horses that bolt their feed without sufficient chewing, or who do not have adequate access to water, are far more likely to choke, regardless of the type of feed, compared to horses that eat at a more leisurely rate. The risk of choke associated with any dry feed can be reduced by soaking the ration prior to feeding.

Foreign Objects: Horse may ingest non-edible materials such as pieces of wood. Cribbers may be more prone to this type of choke, if they happen to swallow a piece of wood or other material while cribbing.

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Wikipedia