Q: I came across this issue on another forum and everyone is stumped. There’s a 2-year-old donkey that first started getting yellow spots on one hoof and then on all four. The yellow spots get larger and the hoof horn peels off in layers. She has been lame with serious stiffness in all four legs, lays down a lot and is now on a half gram of bute twice daily.

Both a farrier and vet are involved in this case. The farrier says it does not look like white line disease and the vet has ruled out laminitis. The hoof lesions and yellow spots may be coincidental to lameness, but both started around the same time. Poison Control does not think the issue is due to a plant that the donkey may have eaten. Has anyone seen anything like this?

— Christine Sizemore

A: Get some X-rays. There may be some issues with the coffin bone or possibly a keratoma.

— Chris Diehl

A: I’ve seen this type of thing twice and both were caused by different factors. One was a selenium overdose. A horse was given a selenium E shot, but was from an area that is naturally high in selenium. The horse’s system was overloaded, causing a blistering effect in the laminae and eventually sloughing off both front hooves. That horse had to be put down.

The other case was a donkey with mold from a wet pasture. Conventional bacteria treatments won’t kill some types of mold…