Part II

In Part I of this two part article on equine colic I broadly classified colics into seven categories. To repeat, they are: Verminous colic; Spasmodic colic; Flatulent and stomach dilation or Gas colic; colic due to Gastric Duodenal Ulcers and Enteritis; Intestinal obstruction due to malposition; Impaction colic; Colic due to pregnancy in the mare; and Azoturia of the intestinal tract. This is a very broad classification of colics but it will aid the ordinary stockman to understand the nature and causative factors associated with the colic syndrome in the equine family.

As promised, in this issue of The Draft Horse Journal I will list some very important measures the readers should be taking to prevent most of these colics in their herds, as well as some of the procedures a veterinarian should undertake to diagnose a case of colic and how to decide if the colic is to be treated medically or surgically.

A proper and thorough physical examination of the horse with symptoms of abdominal pain, including such history as can be provided, should be done as soon as possible after the onset of the condition. It is thought by many clinicians that over 90 percent of those animals showing severe abdominal pain, or colic, can be treated successfully while some four percent may require surgery to correct the condition. Therefore, it becomes imperative that as soon as a colic is observed, professional help should be sought, a diagnosis should be made, and, as a result, the prognosis of the case can be determined. To delay this process may worsen the chances for recovery.

The animal’s owner or attendant should be prepared to give a very good history relating to the present colic. This history should include such information as:

1. The duration of the colic. When was it first observed and where?
2. The severity of pain. Was there any drug or drugs given to alleviate it? If so, what product(s), what dosage and how long ago was it given?
3. Any change in feed, feeding routine or practice?
4. Has the horse urinated or defecated recently?
5. Did this colic follow foaling, exercise or breeding?
6. Has this animal had colic before? If so, when and how often?
7. A history of any vaccinations given and the worming schedule is also an important part of the information passed on to the veterinarian.

This history can be given while the veterinarian is examining the horse. The veterinarian’s examination is very important and should include without fail certain procedures and practices. Following is a list of the basic procedures I believe the veterinarian must follow in evaluating and diagnosing colic.

Evaluation of the pulse and respiration is a must. Most clinicians agree that a weak pulse rate increasing to greater than 80 beats per minute is indicative of shock and the result of a condition whereby cardiovascular damage is being rendered. This condition, tissue perfusion, can be tested by raising the upper lip and pressing the tissue above the incisor teeth with one’s thumb. Normally, the original color will return in 1-2 seconds. This is called “capillary refill time.” Should it take 5-6 seconds to refill, severe dehydration is occurring. Likewise, a 3-4 second time generally indicates moderate dehydration.

The color of these mucous membranes is also indicative of the severity of the colic. Red to dark red or bluish membranes are often seen in severe endotoxic conditions. Often when the animal is approaching death, the same membrane will be a grey to “sickly white” in color.

The respiratory rate is also a barometer of the colic syndrome. Generally, a respiratory rate of greater than 30 breaths per minute is seen in horses with severe colic pain and they will increase with the severity of pain and the production of endotoxin due to the death of a segment of bowel.

Another important part of the veterinarian’s physical examination of the patient is the procedure in which intestinal sounds or movements are listened to and recorded. This is done on both sides of the abdomen. Normally, there are two types of intestinal sounds, each occurring every two to four minutes. One is a short sharp sound heard when the feed or ingesta is being “mixed” in the intestinal tract. The other sound is of longer duration and occurs as the ingesta is being moved through the intestine. In many types of colic, these sounds may be absent for as long as 30 minutes. In contrast, they are often greatly increased in spasmodic colic cases.

There are two procedures which should always be carried out by the veterinarian in every case of colic. They are: 1) The passing of a stomach tube through the nostril of the horse, down the esophagus and into the stomach. This procedure is known as “nasogastric intubation;” 2) A thorough rectal examination of the patient. Let’s look more closely at these two procedures.

The passing of the nasogastric tube should always be done in every colic case without fail. No excuse! The veterinarian should perform the feat! It is often said the horse or mule cannot vomit. If there is gas in the stomach, a well placed tube will immediately remove it with immediate relief of pain to the patient. To remove excess fluid in the stomach, the material must be siphoned away. It is important to note that to siphon off the fluid, repeated attempts have to be made, especially if by rectal examination it has been determined that the small intestine is distended. This procedure will serve as a diagnostic tool as well as preventing the rupture of the stomach.

A thorough rectal examination of the patient should always be done without fail. If the patient is too small or if it is too violent, the procedure can be excused, but for only these two reasons. The rectal exam performed by one who knows what he or she is doing is an extremely important diagnostic tool. A specific diagnosis of a colic can often be made by the examiner. However, in the draft animal, this is somewhat limited due to the size of the abdominal cavity and the length of the veterinarian’s arm. However, the examiner will be able to feel distension of the bowel and certain malpositions of the intestines.

A well performed rectal exam by a knowledgeable veterinarian could reveal the presence of an inguinal hernia, colon displacements and torsion, impactions, intussusception and gas buildup in the caecum.

In his or her examination, the attending veterinarian may take a blood sample and a sample of the peritoneal or abdominal fluid for analysis.

In the long run, only two to four percent of all colics need surgery–the balance can be treated medically. To treat it successfully, one must know what is causing the “colic” or what kind of colic it is. Is it impaction colic, spasmodic colic, or gas colic, verminous colic, colic due to pregnancy or ulcers and enteritis? These can all be treated medically as well as with minor surgical practices such as those used in relieving gas buildup in the caecum. My point is the colic must be diagnosed–not just “treated” by giving the patient a “shot” of Banamine and going home. There are many drugs used today in the treatment of different types of colic occurring in the equine family. Their successful use, however, depends on what kind or type of colic the veterinarian is treating. The veterinarian should make a diagnosis and tell you what it is and how he or she is treating the case. Again, the shot of Banamine and “it’s just a belly ache” is not a diagnosis of the problem and, in most cases, is not an adequate treatment for the condition and the welfare of the patient. I would say if a veterinarian is not sure of his or her diagnosis, he or she should seek advice from other clinicians or refer the case to another equine clinic for further examination.

When should the attending veterinarian refer the “colicky” horse for surgery? This decision should be made as early as possible by all parties and not postponed until the condition of the animal deteriorates to the point where surgery will no longer correct the problem. The following is a list which will indicate surgical intervention for treatment of the “colicky” patient:

1. 100% of colic patients require surgery with the presence of uncontrollable pain if violent pain recurs within one hour after the administration of a potent drug to control it.
2. Motility of the intestines has ceased.
3. A rectal examination has revealed a problem which only surgery can correct.
4. Pulse rate weakening and increasing to 80 beats per minute and higher. Increasing capillary refill time along with the mucous membranes becoming dark red in color.
5. Distension of the abdominal cavity with increased shallow breathing.
6. Gastric reflux with continued pain.
7. Analysis of the peritoneal fluid reveals increased protein and red and white cells plus a change in consistency and color. (If the above has already happened, it may be too late for surgery.)

Are there any signs or symptoms seen in the “colicky” horse that imply the case can be treated medically? Yes, there are a number of them which would point the veterinarian toward a medical treatment. Following is a list of them:

1. Rise in temperature. Fever. This often occurs in a colic due to enteritis which can be treated medically.
2. Cessation of pain - 1 to 2 hours after a dose of a “pain killing” drug such as Banamine is given.
3. Following I.V. administration of 10-12 liters of fluid there are increased bowel sounds with no pain evident.
4. Depression. Head lowered, animal is lethargic. This often occurs in cases of enteritis.
5. Spasmodic colic.
6. Bloat - or gas in the caecum. This can be removed via a needle or trochar.
7. Some impactions can be relieved by non-surgical treatments.

Many of these colics can be prevented. I have had only one colic in my herd of horses since I bought my first pair of registered mares in 1962. It occurred in a stallion which I owned at the time. I caused this one myself. I fed him some hay from a bale which had not gone through its “sweat.” The inside of the bale was still hot. So number 1 is:

1. Do not feed “hot” hay. For that matter, do not feed any forage to your horses that is moldy or dusty.
2. Provide plenty of water in a clean tank or fountain year around.
3. Try to feed grain the same time each day and do not overfeed any grain or grain mixture.
4. Sand colic can be largely prevented in corralled horses by feeding hay in deep bunks with floors in them.
5. Verminous colic can almost be eliminated by a very aggressive worming program, especially in horses and mules up through 3 years of age.
6. Horses with poor teeth on coarse roughages are candidates for colic.
7. Horses fed pelleted or sweet feeds have an increased risk of colic.
8. Horses stabled at shows should be exercised daily to reduce the risk of colic.
9. Place your horses on a full feed of roughage.

I believe this last colic preventative measure is the most important one. The horse eats 80% of the time in a day. It has a small stomach and eats to fill it, then rests while it empties into the intestinal tract. The horse must keep the intestines full and I strongly believe this single fact prevents most of the intestinal displacements. I also believe this practice will prevent ulcers in adult horses.

I have a number of friends in the draft horse world who feed much the same as I, as well as having a similar worming and health program for their stock and it’s a fact that colics in their animals, as well as mine, are almost non-existent.

I’ve tried to write both Parts I and II as simply as I could in order that you, the reader, might better understand “colics.” I could write much more on the subject, but for the owner of horses, it would not be meaningful. Above all, I have informed you what the veterinarian should absolutely do when called to your stable to diagnose and treat a horse or mule with “colic.” I have also given you an insight into the condition as well as the means to prevent almost all “colics.” With this information, the rest is up to you.

By the way, I ended Part I by telling you about a gentleman and his treatment for colic in his horses which he says has never failed to cure them.

Do you think it will work?

I am especially indebted to the following authors and speaker as a source of material to use in this article about equine colic. Another source is my own experience on the subject gained from 56 years as a veterinary practitioner.

·White N.A. – Edwards G. B. (1999) Handbook of Equine Colic

·White N.A. (2005) Lecture on Equine Colic at The Western Veterinary Conference, Las Vegas, NV.