SAND COLIC REARS ITS UGLY HEAD THIS WINTER
Adapted from Sand Colic Article from MI Equine News by Karen Waite
and My Horse University's Horse Nutrition and Health Online Courses
The mild and relatively snow-free winter experienced in certain parts of the country has been great for riding, but not so terrific for your horse’s health. Pastures with sandy soil combined with the lack of seasonal snow cover have resulted in horses nibbling at forage but ingesting sand. This winter, Michigan State University’s Large Animal Clinic has treated a number of sand colic cases that aren’t typically seen in the winter months.
Sand Colic Description
Colic is defined as any abdominal pain, although horse owners typically refer to colic as problems with the gastro-intestinal tract. The causes of colic are numerous, but generally they are related to the anatomy and the microflora of the horse's gastrointestinal tract. While horses can ingest almost any kind of foreign material (sand, gravel, hair), sand is by far the most common one associated with colic. Horses typically ingest sand while grazing very short pastures or when turned out on dirt/sand lots without access to forage. Feeding directly off the ground can also lead to the ingestion of sand or dirt.
Impaction colics are commonly located in the cecum and large intestine where there is a significant change in direction or diameter of the intestinal wall (Image right).
When horses ingest sand, some of it will pass through the GI tract and be eliminated, but because it is heavier than organic material and water, it tends to precipitate out of the ingesta and accumulate in the gut. Mild sand accumulation can cause intermittent diarrhea, alterations in intestinal motility, and colic symptoms that come and go. The large intestine folds upon itself and has several changes of direction (flexures) and diameter changes. These flexures and diameter shifts can be sights for impactions, where a firm mass of feed or foreign material blocks the intestine (including the cecum). Impactions and obstructions can be induced by coarse feed stuff, dehydration or accumulation of foreign material like sand. Horses with an impaction may develop severe colic with or without abdominal distension.
Intestinal Motility: The contractions and other movements by which the intestines move ingesta through the system.
Impactions: A blockage formed by something the horse has ingested.
Signs of colic include:
During a colic episode, you will need to monitor your horse’s condition. The information you gather will help your vet determine how the episode is progressing.
Helpful Hint: Listen for gut sounds by putting your head on the horse's barrel just behind the last rib. You should hear gurgling sounds in a healthy digestive tract. the absence of sounds means there are mobility problems in the gut. Be sure to listen to both sides and practice when your horse is healthy.
Rolling can be a sign of colic, especially if it is repeated and/or violent. Source: Flickr_Sioux.
Biting or looking at their belly is a sign that a horse is colicing. Source: Dr. Judy Marteniuk.
Repeatedly lying down and getting up is a sign of discomfort in a colicing horse. Source: Flickr_pmarkham.
Curling the upper lip (above) can be a sign of pain, but it is not seen as often as other signs.
What To Do Until the Vet Arrives
• Remove all feed. Ingesting any food could make the problem worse.
• Monitor vital signs – heartbeat, respiration, temperature.
• Monitor gum color and capillary refill time.
• Monitor for gut sounds.
• Monitor passage of manure.
• Allow a quietly resting horse to remain at rest.
• Slowly walk your horse if it is rolling, kicking or pawing excessively or seems likely to otherwise harm itself. This may distract it and prevent injury.
• If your horse is rolling violently or throwing itself around, try to get it to an area where it will do the least damage to itself. You must take care to avoid injury yourself, however, for your own safety must be of primary importance.
What Not To Do
• Do not force your horse to walk if it is resting quietly.
• Do not force the horse to stand if it is lying down quietly.
• Do not give the horse any medication before clearing it with a veterinarian. Doing so may mask symptoms and make it difficult for the vet to do an accurate assessment upon arrival.
To give the proper treatment for colic, it is important to determine the cause, so that it can be corrected. The severity of the signs of colic is not necessarily indicative of the severity of the colic, and sometimes it is difficult to determine the exact cause and therefore the correct treatment. For these reasons, make sure to have a veterinarian evaluate your horse as soon as possible. Many cases of sand colic can be treated successfully with medication, while others involving severe impactions may require immediate surgery. Medical management can consist of numerous treatments.
Monitoring a horse’s heart rate and other vital sounds should be done while waiting for a vet to arrive. Heart rate can be measured by the lower left elbow or underneath the jaw and should be between 30-45 bpm. Source: Dr. Judy Martinuk
• Fluids/Electrolytes: The most common form of medical management for colic is the administration of fluids with electrolytes, either via an intravenous catheter (IV) or orally through a nasogastric tube, to rehydrate the horse. If the colic episode is a simple impaction, rehydrating the horse and the impacted manure will help soften the impacted material so that it can pass.
• Pain Relief: Pain relief, often in the form of anti-inflammatory medications, such as flunixin meglumine (Banamine), is often indicated to control the discomfort while resolving the underlying problem. In some cases, drugs that improve the intestinal motility may be given again to help resolve ileus that can cause colic or result from a prolonged colic.
• Oral Laxatives and Lubricants: Nasogastic administration of laxatives (certain electrolytes) or lubricants (mineral oil) is commonly used if an impaction is suspected. The best way to soften an impaction is to use large volumes of water with electrolytes. This will soften the ingesta more effectively than lubricants alone. However, using some mineral oil or other lubricant may be helpful in dislodging or mobilizing impactions of hair or other materials that won’t necessarily soften with administration of oil.
A veterinarian is often making his/ her best guess to determine the likely cause of the colic pain since there is seldom a definitive diagnosis made without surgical exploration. The goal of medical therapy is to support the patient (rehydrate and prevent excess pain) to allow the therapy to resolve the underlying problem. If the pain persists or the horse deteriorates, however, surgical exploration may then be recommended.
Knowing the composition of your soil can be critical in the prevention of sand colic. Horses kept on sandy soils should be fed off the ground to prevent ingestion. Many horses will throw hay out of feeders and onto the ground, however, so another option is to create a feeding area covered in heavy rubber mats that can be swept regularly to minimize sand and dirt accumulation. Preventing overgrazing of pastures will also help minimize sand ingestion. In general, grass should be four to eight inches tall before you allow grazing in a given area (different grass species have different height requirements), and you should pull a horse off that area if the grass gets below two to three inches. Commercial products containing psyllium may help in eliminating sand accumulated in the GI tract, though the data is limited. According to MSU Equine Extension veterinarian Dr. Judy Marteniuk, “it can take weeks or months for sand to be moved out of the digestive track, depending upon the amount present.”
Psyllium: The seed husks from the plantago psyllium plant. Once moistened, psyllium helps the body rid itself of sand by forming a sticky gel-like substance that picks up sand, allowing it to be excreted.
Checking for Sand
Since the accumulation of sand in the gut is one of the most common causes of colic, it is extremely useful to know how to check your horse’s manure to assess if an abnormal amount of sand is being ingested.
When veterinarians take a fecal sample to check for sand, they will often use a rectal sleeve and take a sample from inside the horse’s rectum. This has the advantage of preventing any contamination of the specimen with sand from the ground. However, if you, like most horse owners, are not trained or equipped to do it that way, you can simply wait for a fresh sample. Take half a dozen balls off the top where they have not come in contact with the ground.
Once you have your sample, there are a couple of different ways you can look for sand. One is to put the manure balls into the bottom of a bucket, add water vigorously and swirl or mash the balls to dissolve them. Wait a few minutes or so to let any sand settle; then pour off the liquid and plant material. Keep adding water and pouring it off until the water is clear and any sand is left at the bottom. More than a teaspoon is considered abnormal, especially if you perform the test several times over a day or so and get the same results.
Another method is to take the manure balls and put them into a large, clear, sealable plastic bag (a large Ziploc works well); add water until the bag is almost full; then seal it and swirl or otherwise break up the manure balls in the water. Once they are dissolved, you can shake or swirl the bag; then hold it up by one corner and wait for any sand to settle into the opposite, lower corner. You can also pour off the water after the contents settle. Then add more water and repeat the process as you do with the bucket method.
For more information on checking horses for sand, and managing sand colic.