This section is from the book "The Farmers Ready Reference Or Hand Book Of Diseases Of Horses And Cattle", by S. C. Orr. . Also available from Amazon: The Farmer's Ready Reference;.
This is a species of tumor that has small calcareous or limy bodies interspersed through it. These bodies are from the size of a millet seed to that of a hazel nut, and form sores if located where they receive pressure from the harness. The remedy is to dissect the deposits out and then treat as an ordinary wound.
Callouses about the shoulders or other parts, the result of undue pressure, are best treated by splitting the skin and removing the hard tissue with the knife, then healing the wound.