Age determination in mini-Shetland ponies and donkeys

The accuracy of ageing mini-Shetland ponies and donkeys was assessed by cor relating the appearance of specific dental features with the known ages of 106 mini-Shetland ponies and 63 donkeys. The ages of the animals ranged bet ween 2 days and 26 years. In both species the eruption of the deciduous and permanent incisors occurred later than in horses. On the other hand, the a ppearance of the dental stars on the permanent incisors of mini-Shetlands a nd donkeys was seen at a younger age than in horses. As in most horse breed s, the disappearance of the cups, the clinical crown lengths, the presence of hooks on the upper corner and the presence of a Galvayne's groove are un reliable features for dental age determination in the pony and the donkey. Specific dental characteristics of both the mini-Shetland pony and the donk ey are discussed.