This term is commonly used to describe abdominal pain in the horse. It occurs quite frequently, is usually only moderate and may pass without being noticed. Mild cases can rapidly become severe so should always be monitored carefully. If in the slightest doubt CALL THE VET! All horse owners will be only too aware of the symptoms of severe colic and its consequences.
The principal causes are:
- Gut overload – if excess starchy feed or spring grass or grass cuttings are eaten, high volumes of gas may be produced in the hind-gut by fermentation. This gas can become trapped in the intestines and cause blockage.
- Poor quality (mouldy) feed.
- Eating very fibrous material e.g. wheat straw, poor hay, woodchips etc., leading to blockage (impaction colic).
- Irregular feeding pattern, preventing regular supply of fibre.
- Inadequate water supply.
- Lack of exercise (essential for releasing the gas produced normally by the digestive processes).
- Worm damage to the gut wall and its blood supply.
- Intestinal strangulation (‘twisted gut’).
- Accumulation of sand and other debris in the gut.
- Tumours and other abnormal growths.
- Poor teeth resulting in inadequate chewing of food.
- Gastric and colonic ulcers.
- Working immediately after feeding.
Most of the causes outlined above can be avoided by good management. Correct feeding is also vital. The horse has a complex digestive system, which has evolved to handle high volumes of leafy vegetable matter. the fibrous part of which is broken down by cellulose-digesting bacteria. A dynamic microbial population is maintained in the hind-gut; sudden dietary changes can have deleterious consequences, as outlined above.
A forage-only diet is usually inadequate for the performance horse and will therefore need supplementing.
Nutrients – dense products such as cereal grains, vegetable oils, oilseeds, proteins, and mineral/vitamin supplements are used. Whilst the horse is well able to digest such materials, they are not a natural part of its diet so need to be fed with care.
By combining such feeds with long fibre, for example, chopped straw or alfalfa, it is possible to slow the rate of passage of feed through the small intestine and so ensure maximum digestion of the soluble nutrients such as starch and protein. Replacing starchy ingredients with high quality vegetable oils and proteins, and good quality digestible fibre greatly reduces the likelihood of excess starch and sugar reaching the hind-gut, where fermentation can cause excess gas production. Probiotic supplements and/or yeast can boost the beneficial bacteria in the hind-gut and so help keep it healthy.