Colic in the Sandhills

Jim Hamilton, DVM

The Carolinas are home to an ever increasing horse population and as numbers increase so does the incidence of several types of colic. When bringing a horse to this region there are several precautions to be taken.

In Sandy soil where the main grass is Bermuda; horses, as they graze, will pick up small amounts of sand along with the grass roots. As time goes on, the sand, instead of being passed out in the manure, settles to the floor of the intestines and stays there. The bed of sand becomes heavy with time and it can cause a blockage in the intestinal tract (impaction) and/or a twisted intestine (Due to one segment of the intestine being heavier than the rest).

Once sand is there, getting rid of it takes some doing. Bran, beet pulp, or mineral oil help but are only of limited value when trying to push the sand out. The best treatments are psyllium-based laxatives such as "Metamucil." There are several brands on the market for use in the horse and all are about the same. I recommend feeding the laxative 10 days out of every month. Some people add it to the feed every day and that's OK as long as the manure doesn't get too loose.

The most common type of hay fed to horses here is coastal. It is, unfortunately, not a very high quality type of hay, nutritionally speaking. If a horse has been elsewhere and is used to timothy, orchard grass, or some other variety of hay, making a slow transition to the new diet is important. Bring enough of the old hay with you to last two weeks. Each day give some of the coastal mixed in with the old type of hay. Make sure to shake out the "flakes" so the two types are really mixed - horses are very good at picking out what they like and leaving the rest.

Because the nutritional value of coastal is not the best, you should consider adding some mixed grain to the diet. The addition of only 2-3 quarts (2-3 small coffee cans) per day can provide all that the hay and pasture does not. This is important to the field trial rider because his horse needs all the stamina he can muster for the long endurance rides that are taken.

The third precaution has to do with belly worms (parasites). The sandy soil and the year-round warm temperatures make ideal parasite growing conditions. The bottom line with a worm horse is poor growth, poor condition and poor stamina. So investing in a paste wormer every 30-45 days is very smart. My suggestion is to rotate types of wormers that you use because some worms are better controlled by different medications. First use Ivermectin (Zymectin) then the next month Strongid and the third month Anthelcide. Now, start back with the Ivermectin and rotate through them all year long. On this plan your horse will be less apt to colic and will be stronger and look much healthier.

Many people have the misconception that horses are like cattle - able to thrive on pasture and water. Horses can exist that way by barely thriving. A field trial horse is an endurance horse, much like a marathon runner and should be treated as such if he is to do his best.

e-mail Dr. Jim Hamilton, DVM
Southern Pines Equine Associates