QUESTION: What are hoof growth rings and what does it mean when you see them on a horse at sale?
DR. SCOTT FLEMING: Growth rings are externally visible ridges in the hoof that indicate differences in the rate of growth or quality of a horse's hoof wall. The appearance and number of rings can vary from several consecutive rings to a single or widely intermittent pattern. Growth rings can be indicative of a problem within the hoof capsule or may just be an external map of changes in activity, nutrition, or a systemic disturbance that altered hoof growth at one time.
The average hoof on a healthy adult horse will grow from the coronary band to the ground in approximately one year. Alterations in hoof growth or quality such as laminitis can greatly affect growth rates. For example, the hoof wall at the toe may grow slower than the heels in both laminitic and clubfooted hooves while exhibiting a similar dished appearance. Both conditions may take much longer for the toe to grow to the ground.
Visually, the growth rings will appear small and tightly spaced at the toe and become wider and more pronounced toward the heels where the growth rate is more rapid. We describe these growth rings as being divergent. They are wider in one part of the hoof than another region. They can be divergent in several planes, such as those described previously, or wider at the toe than heels or even wider on the outside of the hoof than the inside or vice versa. These patterns tell us something about the hoof and what forces, either internal or external, are causing growth differences in the hoof. Wider (faster growth) at the toe than heels can mean the heels are compressed or compromised in some manner. We often see this pattern with negative palmar/plantar angled coffin bones.
The hoof may also exhibit a rounded “bullnosed” appearance and the angle of the coronary band is higher than a normal hoof. Rings that are divergent from one side of the hoof compared to the other may result from differential loading due to conformation or can result from more significant insults such as medial sinking or failure of the internal suspension of the hoof. Divergent rings can often result from overloading or imbalance of one portion or structure in the hoof and can be improved through trimming and shoeing that reduces stress in the affected region.
Reading growth rings offers valuable information but is only part of the picture to overall hoof health. The rings that are visible, are a history of where that hoof has been recently, but internally, a hoof can be catastrophically failing without external signs having shown in the wall itself. Physical evaluation, a detailed history, and radiography remain the cornerstones for diagnosing hoof problems.
Scott Fleming, originally from Northeast Texas, grew up riding Western performance Quarter Horses and working with cattle. Upon graduating from high school, Fleming attended farrier school and maintained a quarter horse centric farrier business in Northeast and central Texas until moving to Lexington. He also served in the Marine Corps Infantry for four years.
Fleming graduated from veterinary school at Texas A&M University in 2013. He then completed an internship at Rood & Riddle in 2013-2014, continued at the hospital as a fellow, and is currently an associate veterinarian at Rood & Riddle.
Outside of Rood & Riddle, Fleming enjoys spending time on the farm with his wife, Tina and their two children, Callie and Case . A special interest for Dr. Fleming is participating in Equitarian Initiative trips to Central America to help working equids in the region.
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