Equine colic is still the number one killer of horses, but despite its high profile, it remains a little-understood critical ailment.
Technically, colic means pain in the abdomen. In the worst case, it can be a blockage in the intestines. Since every horse reacts differently to pain, it’s hard to judge the severity of the situation by the severity of the symptoms, but here’s what to look for: The horse is clearly uncomfortable. He may be lying down more than usual, getting up and lying down repeatedly, standing stretched out, standing frequently as if to urinate, turning his head towards his flank, repeatedly curling the upper lip, pawing the ground, kicking at his abdomen, or rolling.
If you suspect your horse is colicking, please call your vet right away. Time is of the essence and delay can truly mean the difference between life and death. Pulsed LEDs and other therapies like acupuncture and acupressure will help to ease your horse’s pain and in some cases, relieve other symptoms, but they should be considered supplemental therapies only. Visit Gladstone Equine’s Library to purchase fine books on equine veterinary care for horse owners.
Recent research on the causes and prevention of equine colic.
Although we have made great strides in the diagnosis and treatment of equine colic, we still know frustratingly little about the causes.
This was the main point that struck me after hearing the lectures at the Fifth Equine Colic Research Symposium, an international conference held in Athens, Ga., this fall.
True we are now able to surgically and medically save more animals from colic, with fewer complications, but we still cannot tell the horse owner exactly why or how to prevent colic. Colic remains the number one killer in horses.
As we have always suspected researchers confirm that colic has many causes, so there will be no single preventative protocol.
Although many equine colic studies in the past were retrospective — that is, researchers gathered information about colic cases and looked for a common factor — a new study that was revealed at the conference was a prospective analysis. It was conducted by the Virginia-Maryland Regional College of Veterinary Medicine and local horse farms. These researchers followed randomly selected horses over a period of time and obtained data. Then a comparison was made between colicky horses and normally based on that data.
Here is a summary from my review of the new information from the Virginia-Maryland study, and from other excellent retrospective studies in Pennsylvania and Texas.
Keep in mind, however, that it’s inappropriate to apply any of these findings to anyone particular colic case. Colic problems are best treated with the help of a veterinarian.
Research supports the recommendation that feeding a horse good-quality fiber (pasture or hay) prevents equine colic.
Some other interesting findings were that:
- Horses that had access to several different pastures, or were on pasture 24 hours a day, were at less risk.
- Horses that received less than 5.5 pounds of grain concentrate a day were at less risk.
- Horses that received more of their energy from grain than fiber were at greater risk.
Dietary Management
There was no apparent difference between sweet feed and pellets on the risk of colic. While traditional horsemen have blamed pelleted feeds for colic, research disproved this bias.
There was, however, a study that showed an increased risk of equine colic with owners who top-dressed a horse’s rations with corn. (This should not be interpreted to say that corn causes colic.) Owners who mixed corn into the ration possibly fed more grain energy than fiber energy, creating a nutritional imbalance. But good quality corn mixed into balanced nutritional benefits and has not shown a definitive association with colic, as long as fiber remained the primary energy source.
Equine colic was highly related to feeding changes. Two of the studies showed that recent feed changes increased colic risk; farms with greater than six feed changes per year were also at risk. The theory: feed changes have an effect on the horse’s intestinal bacteria.
Another major factor in the colic scenario was water management. Horses turned out for exercise in a paddock with no water for as little as one to two hours had a significantly increased risk of colic.
Breed, Use and History
Two studies showed that the Arabian horse was at risk of colic. Researchers, however, were unsure if the data was biased. Perhaps the Arabian horse reacts more to abdominal pain than other horses, or perhaps the owners of Arabians watch their animals more closely and report colic more frequently.
In one study, it appeared that crossbred horses were at less risk of colic. This finding may be biased because of the ways these owners use their horses. Much more research is needed before we can definitely assign relative risk of colic to certain breeds of horses.
The study also showed that horses cared for by someone other than the owner are at higher risk of colic.
Horses used for riding lessons were at less risk than horses in race training.
Any changes in exercise regimens or stabling changes increase the risk of colic. Apparently, horses that had a decrease in exercise and an increase in stall confinement were at greater risk of colon impactions. Researchers theorize that when a horse’s exercise is decreased intestinal fluid shifts can occur, resulting in a blockage.
Some of the most significant risk factors were for horses that have had colic before. Once a horse has had colic, research showed that he is more likely to suffer from it again. Also, horses undergoing treatment for something other than colic are at higher risk of suffering colic as a secondary complication.
Another concern of horse owners is: to what extent do age and parasites influence the incidence of equine colic?
Although age factors are still confusing, according to one study, horses between ages two and ten were more likely to colic than older horses.
As for parasites, although they contributed to colic, they are no longer thought to be the primary cause, and no correlation could be made between deworming programs or fecal egg counts and colic. (Of course, deworming will always be basic to good horse care.)
Future Research
The question of mold toxins and colic has always been an area of concern. Recently, researchers at North Carolina State University have looked at whether certain mold toxins or combinations of mold toxins found in hay or grain may play a role in equine colic. However, more definitive work needs to be done before a particular mold toxin can be confirmed as the cause of a colic episode.
Because most horse owners don’t have adequate pastures to maintain their horses entirely on grass, is there a way to alter the grain diet and lessen the risk of colic? Possibly.
New pilot studies have shown that enzymes, digestive bacteria, yeast cultures or ammonia scavengers (as offered in Triple Crown feeds) can improve digestion and modify the intestinal environment. The most inconsistent feed fed to horses is hay. Could the use of more consistent “quality” forages lessen the risk of colic? Would the mixing of a consistent fermentable “hay chop” (such as Dengie Forages) with grain rations alter colic risk?
All of us should support future research projects on the causes of equine colic. Get involved in your breed associations, horse clubs, and universities to help raise revenues to fund these costly but needed projects. Quality research is our only hope of lessening the impact of equine colic.