An evaluation of the accuracy of ageing horses by their dentition: a matter of experience?

There is a widely held belief that a horse can be accurately aged by an examination of its teeth but this belief has recently been questioned. In this study photographs were taken of the dentition of 434 thoroughbreds of known age. Four experienced equine clinicians provided estimates of the ages of the horses from the photographs. A comparison of the estimated and true ages showed large discrepancies in many cases and the discrepancies increased as the horse's true age increased. The results show that the ageing of horses from their dentition is an imprecise science. It is suggested that written records of the dental features are made on each occasion when a dental examination is made and that veterinary surgeons advise clients that estimating a horse's age from dental criteria can provide no more than an 'informed guess'.