Ageing domestic sheep (Ovis aries L.) from growth lines in the cementum of the first incisor

First incisor teeth from known-age domestic sheep were examined to determine whether annual lines developed, and to test 3 processing techniques. Fluorescing lines in undecalcified, unstained transverse sections indicated completed years in 44 % of teeth. Dark lines in decalcified, stained transverse sections indicated completed years in 8 % of teeth. Dark lines seen by reflected light in undecalcified roots ground transversely by hand indicated completed years in 62 % of teeth. Grinding by hand was the simplest, quickest, and most dependable method.