Ask the vet:Colic

If you own horses long enough, chances are you will be faced with the threat of colic. Get the answers first by posing your questions concering the topic of colic to our month's AAEP expert, Dr. Christina Hewes.

Question: I have a 17-year-old Thoroughbred with a history of gas colic - usually about 3 episodes a year - and is a mild cribber. He is turned out on pasture 24/7. A couple of months ago, our barn switched feed and since then, he has increased his cribbing and has become more gassy. With his history, my veterinarian believes the cribbing is a sign of gastric distress brought on by the feed and recommended that I find a different feed (he said that the new feed might have too much sugar as the feed bag says that the pellets contain molasses). What do I need to look for in a feed? He is already getting pre- and probiotics.
I agree with your veterinarian that this new food seems to be upsetting his gastrointestinal tract. I would look at the previous feed that did not cause problems and switch back to the original feed or find one very similar to it by looking at the ingredients, not the percentage of protein, fat, or fiber. I do not know which ingredient upsets your horse's system in the new feed. It could be the molasses or it could be something else. The only way to know is by comparing the old and new feeds.
Question: My 22-year-old mare coliced and after the episode, the veterinarian recommended I put my horse on an ulcer medication. Why would my veterinarian make this recommendation? I have owned my horse for 12 years and she is a very easy keeper as this colic episode was her first that needed the attention of a veterinarian. In the past, she has had two mild gas colics.
This is a tricky question since I did not see your horse. A large percentage of horses have been found to have ulcers in their stomach. Ulcers can only be accurately diagnosed by placing an endoscope (medical camera) into the stomach to visualize the inside lining. Many vets have found that treating for gastric ulcers can resolve colic in some horses, whether or not the horses have ulcers. It may help to lower the gastric acid levels, which the ulcer medication does, to reduce some intestinal discomfort. Although your horse seems to be at a low risk for ulcers, ulcers or intestinal irritation still could be present. If the medication helped your horse, there may have been something irritating the intestines that reducing stomach acid helped.
Question: My horse went into colic mulitple times over the winter. Finally, the last veterinarian that came out to treat my horse, determined that the horse needed to take Sand Clear every day. The product says to only take a week a month but the veterinarian insists it must be taken every day due to the shale on the property. Is it safe to feed Sand Clear everyday?
There are different opinions on the use of psyllium, which is the active ingredient in Sand Clear. I prefer to give it one week of every month. Horses can develop the ability to digest psyllium in the colon, especially if they are receiving it everyday. This would prevent the psyllium from moving the sand through the colon. By feeding it intermittently, the horse is less likely to develop the ability to digest it so it can still help move the sand/silt through the intestine. Another thing to consider is using probiotics to help keep the intestinal bacteria working appropriately. This can improve the colonic motility and help move sand out. One study found significantly more sand was passed through the intestinal tract when probiotics and psyllium were given together.
Question: Does coastal hay cause colic?
Coastal Bermuda grass hay has been associated with feed impactions in the ileum, which is a portion of the small intestine. Some of these impactions resolve with nasogastric tubing with water, mineral oil, and electrolytes, while a small number require surgery. With that being said, many horses eat coastal hay regularly without a problem. Having good quality hay is very important so if you need to feed coastal hay due to your situation, many horses will tolerate it without colic.
Question: I have an 8-year-old Thoroughbred mare that developed spasmodic colic after getting cast in the stable two years ago. Since then, she has had a number of spasmodic episodes with the last one for a period of 36 hours. She lost a lot of weight and is currently on haylage and a high fiber, slow release mix. She is getting little turnout or grazing, but is being worked and hacked out 3 to 5 times a week. Is there anything else I should do to maintain her and stop the incidents of colic?
Chronic colicers are always tricky to manage. In some of the scientific studies they have found that horses that live on pasture have the lowest rate of colic. If you could find a situation where your mare is turned out for most of the day, it may help her. The movement in the pasture seems to improve the ability of the intestinal tract to move gas and feed material. If a pasture is not an option, getting her out every day for some activity is important. It can be just hand walking if you do not have time to ride. You may also want to note if there are certain types of feed or weather patterns that correspond to her colic. If she colic's when it rains, you want to ensure that she is getting some extra exercise on those days. If she colic's when fed a certain type of hay, try to find one that seems better.
Question: The stable where I board my horse has very sandy pastures. The horses are in a dry lot for all months except a few in the summer when the grass is tall enough. Is it a good idea to give my gelding a 7-day dose of a sand-clearing supplement like Arenus Assure Plus (a pelleted psyllium based feed additive with synbiotics and controlled release digestive aids. This patent pending pelleted combination of psyllium and digestive aids removes all of the sand and silt from the large colon)? On the other days of the month, I give him just the regular Arenus Assure (a granular daily feed additive with psyllium and synbiotics that improves the environment of the colon and improves normal digestive processes). I feel these are good preventative steps - as I have already lost a horse to sand colic. Do you feel this is a safe plan?
Sand colic is a difficult type of colic since horses tend to ingest sand when eating from the ground. The only way to prevent sand colic is to prevent sand intake. Feeding inside a barn or on a mat can reduce sand intake. Since this may be difficult in your situation, a one week course of psyllium is a good idea. I tend to have horses fed psyllium for one week a month and then have no psyllium for the following three weeks. This seems to prevent horses from obtaining the ability to digest psyllium, which is possible if fed psyllium constantly. For the products you are looking at, they both have psyllium in them so I would want to ensure that the Plus version has more psyllium than the other version. I might also try to find a supplement without psyllium that can be fed daily and add the psyllium for one week per month. Also, I do not think there is a  feed supplement that can remove all psyllium from the colon despite the label claims. If a product worked that well, then we would recommend it to all horses. At this time, intermittent psyllium seems to be the best way to prevent a large buildup of sand in the colon.
Question: Why is it so important to not let a horse with colic roll? 
This is a very common question. It is important to not let a horse with colic roll since they can injure themselves when they are rolling. The rolling rarely causes the intestine to move into an incorrect position but is a sign of the pain caused by the abnormal position of the intestines. If the horse is trying to roll, I recommend walking them to distract them from the pain and possibly relieve the cramping from the colic. Walking can also help the gastro-intestinal tract expel gas, which may relieve the colic pain. If the horse is sitting or lying quietly, the horse can be left alone until the veterinarian arrives to examine him. If the horse is uncontrollable and trying to roll, everyone needs to stay out of the way so they are not hurt by the painful horse.
Question: What diagnostics should be performed on an 8-year-old, otherwise healthy, gelding that frequently (every 1-3 months) suffers from low grade gas colic? His manure consistency and volume remains unchanged, his feed remains the same as does his stress level. He lives in an acre field (dry lot under trees) with a 21-year-old companion. They both have access to ample fresh water and frequent small feedings of quality grass hay. The hay is fed in slow nets tied inside clean plastic livestock tanks. Aside from 1/4 cup flax, mineral supplements, and regular psyllium doses mixed in grass hay pellets, and a carrot or two, he's not ingesting anything other than hay (the bark on the trees remains untouched, the fencing is plastic/Centaur, the field is covered with fine pine chips). He has had a tendency to colic since my daughter purchased him as a yearling, but now that he's living at our home and not a boarding facility. We notice his discomfort more often (appetite diminished, lying down and getting up, flehmen response). He often walks and passes gas as his way out of the discomfort, but we need some help for the poor guy!
This is a complicated question since it sounds like you have made a good environment for him. It sounds like your gelding is either producing too much gas or has a motility disorder in his intestinal tract, which could be secondary to inflammation. I would start with a fecal exam to look for parasites, even if he is regularly dewormed. I would then consider adding a probiotic to his diet since he is producing excess gas on a regular basis, which may help normalize the bacteria in his colon. If he is on any medications, I would ensure that he needs them and consider side effects, which could upset his gastro-intestinal system. Another thing I like to do is ensure he is getting enough activity with daily exercise form riding, lunging, or hand walking. Although he is in a pasture and should be walking around often, he may not be active enough. Another diagnostic is a gastroscopy to look for gastric ulcers even though he is in a low stress environment. A final option is to try a different type of hay to see if it produces less gas in colon. If you change his hay, it should be done gradually by adding small amounts of the new hay to his old hay. The amount of new hay should slowly increase and old hay decrease over a 1-2 week period to transition him to the new hay.