Send ANY horse, horse farm, or equine industry-related question to the Equine Science Center and our faculty and staff have the knowledge, expertise, and resources to provide individual answers based on your inquiry. Please note that while we do have faculty with veterinary expertise, if your horse appears to need medical attention or is in pain, please contact your veterinarian immediately.  While we specialize in equine nutrition, care and management of the equine athlete and the older horse, equine exercise physiology, environmental stewardship and best farm management practices, and horse industry economics and policies, we can reach out to our colleagues from around the world to find the most knowledgeable person in the field to answer your question. Send your questions in our provided form below. Your response will be emailed back to you, and may be posted to our website for future reference.

Questions & Answers

Antibiotics can cause loose stool. They kill the bad bacteria causing the sickness, but also kill good bacteria that are used in the digestive process of the horse. It is sometimes recommended to feed a probiotic along with the antibiotic to help replace the good bacteria that are being killed by the antibiotics. You can continue the probiotics after the antibiotics are finished and monitor the stool. Over the course of a week or so the stool should get back to normal and the probiotics can be discontinued. If the stool does not get back to normal you should consult with your veterinarian. However, if a horse is under veterinary care and its condition changes such that it develops new clinical signs (develops diarrhea) the veterinarian should be made aware of the situation. While antibiotics can cause diarrhea, the diarrhea may also be a sign of a progression of the horse’s illness and the horse may need more than a probiotic.

 

This sounds like a horse with an abnormally locking patella (knee) or “intermittent upward patellar fixation”. There are three ligaments that go around the patella in the stifle of the horse (the joint above the hock in the hind leg, similar to a human knee). These ligaments around the patella are used to lock the horse’s leg in place so they can sleep standing up. Usually the locking mechanism can unlock itself very rapidly when needed, e.g. if the horse spooks. However, sometimes there is a problem where the lock gets stuck and the horse will be unable to move its leg for a period of time.

A horse's stifle joint as seen from the front.

There are three main causes of this locking problem: 1) a horse that is unfit might not have enough muscle tone in its hind limbs to trigger the unlocking response, 2) horses with unusually upright hind limb confirmation are more prone to abnormal fixation, and 3) some horses have ligaments that are longer than average, so the locking mechanism gets stuck more easily in them than in most individuals.

 

Given these reasons, there are several ways to go about correcting the problem:

  • Exercise – horses that are unfit will benefit from strengthening of the hind limb muscles. Increasing fitness of the horse will also help increase the effectiveness of other treatments.
  • Corrective shoeing – shortening the extension phase of a stride will lessen the likelihood of the mechanism getting stuck. Use a rocker shoe, or roll the toe. Egg bar shoes or wedge pads are commonly used.
  • Hormonal therapy – estrogen has been found to help these horses. This will help tighten the ligaments that cause the problem.
  • Blistering – infusing an irritant into the joint to create scar tissue to inhibit the locking mechanism in the joint. This is not generally recommended, but could be useful in severe cases.
  • Ligament resection – last resort and is not generally recommended.

Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.

Antibiotics can cause loose stool. They kill the bad bacteria causing the sickness, but also kill good bacteria that are used in the digestive process of the horse. It is sometimes recommended to feed a probiotic along with the antibiotic to help replace the good bacteria that are being killed by the antibiotics. You can continue the probiotics after the antibiotics are finished and monitor the stool. Over the course of a week or so the stool should get back to normal and the probiotics can be discontinued. If the stool does not get back to normal you should consult with your veterinarian. However, if a horse is under veterinary care and its condition changes such that it develops new clinical signs (develops diarrhea) the veterinarian should be made aware of the situation. While antibiotics can cause diarrhea, the diarrhea may also be a sign of a progression of the horse’s illness and the horse may need more than a probiotic.

 

This sounds like a horse with an abnormally locking patella (knee) or “intermittent upward patellar fixation”. There are three ligaments that go around the patella in the stifle of the horse (the joint above the hock in the hind leg, similar to a human knee). These ligaments around the patella are used to lock the horse’s leg in place so they can sleep standing up. Usually the locking mechanism can unlock itself very rapidly when needed, e.g. if the horse spooks. However, sometimes there is a problem where the lock gets stuck and the horse will be unable to move its leg for a period of time.

A horse's stifle joint as seen from the front.

There are three main causes of this locking problem: 1) a horse that is unfit might not have enough muscle tone in its hind limbs to trigger the unlocking response, 2) horses with unusually upright hind limb confirmation are more prone to abnormal fixation, and 3) some horses have ligaments that are longer than average, so the locking mechanism gets stuck more easily in them than in most individuals.

 

Given these reasons, there are several ways to go about correcting the problem:

  • Exercise – horses that are unfit will benefit from strengthening of the hind limb muscles. Increasing fitness of the horse will also help increase the effectiveness of other treatments.
  • Corrective shoeing – shortening the extension phase of a stride will lessen the likelihood of the mechanism getting stuck. Use a rocker shoe, or roll the toe. Egg bar shoes or wedge pads are commonly used.
  • Hormonal therapy – estrogen has been found to help these horses. This will help tighten the ligaments that cause the problem.
  • Blistering – infusing an irritant into the joint to create scar tissue to inhibit the locking mechanism in the joint. This is not generally recommended, but could be useful in severe cases.
  • Ligament resection – last resort and is not generally recommended.

Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.