Call the vet, or wait and see? When concerned about a foal’s health–particularly when infections are suspected–waiting is never a good idea. Osteomyelitis in young foals, for instance, requires immediate treatment, as Alastair Kay, BVSc, MS, Dipl. ACVS, MRCVS, equine surgeon at Minister Equine Clinic, in North Yorkshire, U.K., relayed at the 2011 American Association of the Equine Practitioners convention, held Nov. 18-22 in San Antonio, Texas.

"Osteomyelitis is an infection of either bone or bone and cartilage combined," Kay explained. "If infection develops in bone and/or cartilage close to joints, the chances of achieving a high-level athletic exercise may be poor, particularly if the infection is aggressive, a large area is involved, or if treatment is initially delayed."

Osteomyelitis is relatively common in young foals less than 4 weeks old, and it can affect all bones of the skeleton. Long bones such as the cannon bone, small bones such as in the lower hock or knee joints, or bones within the foot are most commonly affected.

"Infection of the patella (equivalent to the knee cap in humans) is uncommon in foals, but when it happens can result in prolonged and severe stifle joint infection," added Kay