What Are the Causes of Colic in Foals?

The biggest fear of every horse owner is colic, especially a young foal with colic. A seemingly healthy foal can become ill with colic symptoms within hours. There are many causes of colic in foals, but some are more common than others. Horse owners should be proactive and try to prevent some of the more common causes. Always consult a veterinarian when dealing with colic in foals.

  1. Hair Ball Colic

    • Most foals are born during early spring in February or March, unfortunately this is also when mares shed their winter coat. Foals can often be seen nuzzling the sides of their dams or chewing on their tails. If the mare is shedding profusely, or the foal chews on the mare's tail, the foal can accidentally ingest a large amount of hair which can lead to a hair ball (trichobezoar) colic. Equine practitioners recommended that pregnant mares have their winter hair shaved off their stomach and sides before foaling to avoid hair colic in their foal. Brushing the mare daily to remove loose hair can also help to avoid hair ball colic in foals.

    Overo Lethal White Syndrome

    • Overo Lethal White Syndrome in foals is caused by breeding both a stallion and mare that are each positive for one Lethal White Overo gene or LWO. The breeding of two Lethal White Overo carriers can result in up to 25 percent of the resulting foals being born with Overo Lethal White Syndrome or OWLS. Foals born with this syndrome are born without a fully functioning digestive tract. While they may appear normal when first born, they start to colic soon after they start nursing, as they cannot eliminate waste. Lethal White Syndrome is fatal in all foals born with this syndrome.

    Parasite Infestation

    • The most common parasites seen in foals are Ascarids, also known as roundworms. Foals pick up these worms from the manure of other horses, or through the milk of their dam. Ascarids travel to the small intestine and begin to hatch hundreds of eggs, which in turn can cause colic, pneumonia and diarrhea. Pregnant mares should be dewormed immediately before or after foaling to avoid these parasites being transmitted to the foal. Foals should be dewormed starting at eight weeks of age, and then every six to eight weeks until the age of one to two.

    Meconium Impaction

    • Meconium is the first waste passed by a newborn foal and can be very hard and sticky. This can make it difficult for some foals to pass, which in turn can cause a foal to exhibit colic symptoms. Colts are at a higher risk of meconium impaction then fillies, due to their pelvis being more narrow then a filliy's pelvis. For mild meconium impactions, veterinarians recommend foals be given a mild soap and water enema to soften the meconium and make it easier for the foal to pass. Enemas given to foals must be given very carefully to avoid perforating the rectum.