Q: I have heard that the practice of purposely keeping young horses thin to help with soundness later in life is fairly common. Is there any proof this works?

A: Obesity in young horses is something you want to avoid; however, it is important to make sure your foal or weanling is not too thin! Ribs should not be visible, but should be easily felt when you run your fingers over the animalโ€™s flank, and the loin, croup, and neck should not have any bony structures visible (a 5 on the Henneke body condition chart).

Osteochondritis dissecans (OCD), developmental bone lesions associated with abnormality of the cartilage within the joint, is always a risk when raising young horses. Finding a happy medium in body weight is a good start in preventing OCD.

Long bones in mammals are developed through bony replacement of a cartilage skeleton in the fetus. By the time the animal is born, the majority of the bone is bony tissue; however, there is still an area of cartilage present near each end of the long bones called the โ€˜growth plateโ€™ which allows the bone to continue to grow as the animal ages. Sometimes the replacement of cartilage with bone is incomplete and results in thickened and retained joint cartilage which has an abnormal structure and causes the integrity of the joint to be poor. During the period of rapid growth from four months to one year, extra weight should be avoided to prevent undue stress on this cartilage, as young horses are most vulnerable to bone and joint disease.

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