| Founder in the Mini Horse
It is a painful inflammatory condition of a horse's laminae, tissues between the wall and the coffin
bone of the foot. Founder usually affects the front feet, but it can occur in all 4 feet.
The laminae tissue actually comes apart and detaches from the coffin bone causing it to slip. This
puts pressure on the sole of the feet and creates a very painful condition that can cause a fever
and shaking of the muscles of a horse.
The coffin bone can penetrate the bottom of the horses foot. In this case, the horse is in a
hopeless condition and is usually put down.
The main cause of founder in miniature horses is overeating, but overuse on a hard surface (road
founder), retained placenta in the broodmare, or drinking too much water while over-heated can
also lead to founder. Whenever a high fever occurs, a horse can become foundered. Other causes
include over ingestion of grass (grass founder), administration of steroids, diarrhea and Cushings
disease. Finally, founder can be from idiopathic causes (unknown causes).
Symptoms of founder:
Heat and pain in the foot causing the horse to avoid putting his weight on the affected feet. The
hooves will be hot to the touch.
What to do:
Call the veterinarian. Cool his feet with mud or water, and confine the horse in an area with a deep
bed of straw for cushioning until veterinarian help arrives.
The veterinarian will give laxatives to clean out the digestive tract and inject anti-inflammatory
drugs and antihistamines. A special diet and hoof trimming care will be prescribed. In some
instances nitroglycerine cream will be prescribed to increase blood flow to the feet.
Standard preventative measures include:
1) Prevent obesity
2) Do not allow horse to eat black walnuts
3) Any diet changes must be done gradually
4) Avoid excess grain in diet
5) Maintain feet by regular trimming
6) Early evaluation and treatment of fever- temp above 101F
7) Ensure that a mare passes her placenta within 3 hours of foaling