Gastrointestinal Problems in Horses

Gastrointestinal Problems in Horses: Colic is not a specific disease but a disease complex, created in many ways. There are special types of colic, but the primary cause of difficulty in all cases is a distention of the stomach or intestine, which produces abdominal pain.

Equine Colic One type, called physical colic, which produces a blockage of the intestines, has many causes: bad teeth, compactions of lush green feeds, obstructions in the stomach brought about by foreign matter, grain compaction, strangulations of the intestine (twisting), and bloodworm infestations. All of these factors can cause distention, gas, and fluid accumulation, the signs associated with colic.

Another type of colic, called transient colic, is brought on by an inflammation of the intestines from parasites, microorganisms, poisons, or even spasms of the intestines resulting from such things as consumption of cold water when a horse is excessively hot, thunderstorms, and other factors that cause a horse to become excited. Signs of colic include a slow to sudden onset of pain, which may be intermittent. Pain may cause depression and excessive sweating, even when the horse is idle.

The pulse may reach 80 to 100 beats per minute. Affected horses walk stiffly, kick toward the stomach, or bite at their flanks. They may assume a “sitting dog” position. Advanced stages may show very red mucous membranes around the mouth, later changing color to blue, indicating a restriction of oxygen supply from the blood.

The temperature may increase, up to 102 to 103 degrees Fahrenheit. By placing one ear against the abdomen of the horse, you may hear a foaming or explosive gas noise. Respiration is usually very shallow or labored. A definite sign is to see the horse doing continuous rolls on its back.

A healthy horse may lie down in the dust and roll a time or two, but it usually does not continue this at length. A horse affected by colic may rub the hair off its back and head, trying to get relief from the “tummy ache.” If the cause of distention is not removed, death often occurs within 12 to 48 hours. The most important factor in treatment is judging the severity of the attack. Mild colic can be relieved in an hour or so by simply walking the horse.

In more severe cases, it could be fatal. Because of the intense pain, it is necessary to get relief right away in severe cases. A veterinarian should be called at first suspicion; the animal should be kept on its feet and walking until the veterinarian can get there. Do not allow it to lie on its back and roll, as this can cause further twisting of the intestines and compound the problem.

Treatment usually involves the administration of injectable pain relievers and purging with mineral oil, a mild lubricant. Further treatment may be necessary, depending on the cause of the obstruction. The pain may be brought on by a variety of disorders, including “sand colic,” which produces stretching of the intestinal tract and parasite blockage of the intestinal tract.

Actually, 90% of colic cases are caused by parasitic infestations, especially strongyles (Verminous Arteritis), reducing or blocking the flow of blood to segments of the intestines. Although colic should not be confused with the founder (laminitis), an attack of colic can lead to the crippling disease of the feet (laminitis), to be discussed later.

Cantharis Poison (Blister Beetle or Spanish Beetle Poisoning): The Spanish beetle, often called “blister beetle,” which is very common in many parts of the southwest, can produce severe pain and even death to a horse that ingests sufficient quantities of them.

These poisonous insects often feed on alfalfa and may be baled with hay. The dead beetle, eaten by the horse along with the hay, produces a toxic substance that can cause severe irritation to the mouth and intestinal tract. The horse will show signs of colic, but the pain is not relieved when treatment is applied. There is no effective treatment once the situation occurs.

The only preventive method is to control the beetles in the hay fields. Young colts are very susceptible to beetles, and cantharis poison often occurs when colts follow the mother, eating tender leaves that have been shaken out of alfalfa hay. The beetles are typically in the leaves, and the colts absorb an abnormally large amount because of their selective feeding. Choking Gasping for air is a typical sign of choking and can be related to the same situation that occurs in humans.

It may be a mild form of choke or a relatively severe case that could cause complete blockage and eventual death. It is not uncommon for horses to choke on ears of corn, apples, or fruit that a well-meaning horse owner may offer to them. Most often, the blockage will pass due to the motion of the esophagus, but if the condition persists for 3 or 4 hours, a veterinarian should be consulted.

Although little can be done to prevent a horse from choking on an ear of corn or similar morsel that he accidentally comes upon, choking can be prevented when feeding horse tidbits such as apples by simply splitting the apple with a knife so that there is no round surface that might completely block the passage of air.

Verminous Arteritis, Mesenteric Arteritis, and Bloodworm Colic Strongyle (worm) infestations produce an intestinal upset due to blockage and inflammation of the mesenteric arteries. This parasite, which migrates through the bloodstream, can accumulate to the point that complete blockage occurs, producing a rupture and killing the animal. In other cases, it can create a colic-like syndrome.

The best prevention is to treat very young horses at four to six months of age with a deforming agent and continue this deforming program three to five times a year for the life of the horse. In the event a preventive program has not been established, treatment for the condition may include massive doses of thiabendazole or drugs recommended by a veterinarian. In any case, once the condition occurs, it should definitely be handled by a veterinarian because of the grave nature of the situation.

The preventive program may easily be handled by the layman once proper supervision has been given by a veterinarian or other trained personnel. Simple Diarrhea Although it does not occur in horses as often as in cattle and other domestic animals, diarrhea does occur in horses and is brought on by parasites, an abrupt change of feed, engorgement by young foals with too much milk, and numerous bacterial and viral diseases.

Diarrhea is not a predominantly dangerous situation and can usually be controlled by relatively simple means. Kaolin or pectin-type products may be used as a mild attempt to bring the disorder under control. Usually, this will work, but if anything stronger is needed, a veterinarian should be consulted.

Colitis X (Acute Colitis)

This condition is a serious inflammation of the large intestine and often occurs in quarter horses and racing animals. The signs are similar to simple diarrhea, but the condition is more sudden and profuse. The disease is typically secondary to stresses such as a respiratory disease outbreak three to four weeks prior, very hard training for a race, or traveling over long, tiring distances. The culprit is rapid dehydration caused by watery diarrhea.

This is followed by the production of toxins such as salmonella, E. coli, and clostridium, which creates a severe infection and inflammation as a result. The disease is so insidious that a horse may appear slick and fat, eat its evening ration, and be dead the next morning. Treatment involves long-term oral antibiotic therapy, anti-inflammatory drugs, intestinal Protestants, and a tremendous infusion of intravenous fluids.

If the antibiotics can kill out the toxins, mainly salmonella, rehydration is effective, and adequate calories and nutrition can be maintained, then the animal has a chance to redevelop the immune system and survive. Antiserum can be purchased to protect against acute colitis, and there is now a salmonella vaccine to care for the major toxin, but these are preventative measures only. A horse that is diagnosed with acute colitis must begin treatment immediately. 

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