George W. Pope

“ DETERMINING THE AGE OF CATTLE BY THE TEETH. The age of cattle can be approximated closely by the appearance, development, and subsequent wear of their second incisor teeth. Cattle have eight incisor teeth, all in the lower jaw. In the calf at birth two or more of the temporary or first incisor teeth are present. With the first month the entire eight incisors have appeared.
Fig. 1.—Internal face of incisors of the calf.
As the animal approaches 2 years of age the center pair of temporary incisor teeth or pinchers are replaced by the permanent pinchers which at 2 years attain full development. ”

“ After 6 years the arch gradually loses its rounded contour and becomes nearly straight by the twelfth year. In the meantime the teeth have gradually become triangular in shape, distinctly separated, and show the progressive wearing to stubs. ”