A Systematic Approach to Estimating the Age of a Horse

The examination of the upper corner incisors (UCI) is of great benefit when estimating the age of a horse. Until approximately 5 years of age the UCI will be deciduous. The shape of the UCI as a permanent tooth will progress from wider than tall (similar to a rectangle laying on its side) at 5 to 6 years to square shaped at 9‐10 years. The exposed tooth changes to taller than wide (similar to a rectangle standing on end) at 14 to 15 years of age. The authors suggest that by using the UCI to first categorize the age of the horse, other historically used indicators then can be applied to further refine age estimation. Authors’ address: Texas A&M University, Large Animal Medicine and Surgery, College Station, TX 77843-4475. r 1999 AAEP.