Ask the Vet Video on Cannon Keratosis on Horse Legs

Updated June 6, 2025

In this video, Dr. Lydia Gray answers a viewer question about fungus horses get on the front of their cannon bones on the back legs. She discusses what cannon keratosis in horses is (also known as cannon crud, stud crud, or cannon dermatitis) and how this skin condition may be treated.

Please note, it is important to involve your veterinarian in the diagnosis and treatment of horse health issues. Working under the guidance of a knowledgeable horse health expert may help you avoid aggravating your horse's delicate skin with strong products, scrubs, or manually picking at the crud.