Doctor Bill Kvasnicka, State Extension Veterinarian. The beef cow has a relatively short life span. After their peak productive age, breeding market value usually declines as the animal gets older. Year branding or ear tag numbering are good methods of permanently identifying the age of cattle. These practices usually add value when selling bred cows.
Buyers can bid with confidence on the age of cow they are purchasing.
However, many cattle ranchers are unable to accurately identify the ages of their cattle. The approximate age of cattle may be determined by examining the teeth as illustrated in Diagram 1. The tooth method of aging cattle involves noting the time of appearance and the degree of wear on the temporary and permanent teeth. The temporary or milk teeth, are easily distinguished from the permanent teeth by their smaller size and whiter color. Under rough feed conditions, such as desert rangelands, teeth are worn at a much faster rate.