Dentition is the development of teeth and their arrangement in the mouth.91 For many years,
producers, veterinarians, and exhibitors have used dentition to make general age determinations.
Dentition will vary from herd-to-herd and animal-to-animal, because of the animal’s genetics,
diet, and the varied geographical locations in which they are raised. When the age of an animal is
not known, (or when there are no birth certificates) the best and most practical way to determine
age is by an examination of the teeth. There are three types of teeth found in the bovine: incisors,
premolars, and molars. Incisor teeth are found in the front of the mouth, but they are absent from
the upper jaw. The premolars and molars are found in the back of the mouth and are present in
both the upper (maxilla) and lower (mandible) jaws.
At birth, calves have deciduous teeth, known as temporary, milk, or baby teeth. The deciduous
teeth are lost as the animal ages and they are replaced by the permanent teeth. Calves have a total
of 20 deciduous teeth. There are no deciduous molars and a deciduous premolar is not present.
Gradually permanent teeth replace deciduous teeth.
The deciduous incisors differ from the permanent incisors in being much smaller. The crowns
(that part of the tooth that is covered with enamel) of the deciduous incisors are narrower than
the permanent incisors and they diverge more from the base (at the gum line) of the tooth to the
apex when compared to the permanent incisors.
Cattle 14 months of age would have a full set of deciduous incisors. All four pairs of teeth are
temporary and firmly in place. The teeth are short, broad and usually have a bright, ivory color.
There is usually space between the Di 1 incisors. Other incisors may touch on the inside corner at
the top of the tooth. As the animal ages, the deciduous teeth become loosely set in the jaw. The
teeth appear longer and narrower than in younger animals and the teeth may or may not be
touching at the upper corners.
The permanent incisors usually erupt at an angle and straighten into a definite pattern with
growth. Animals with eruption of one or more central incisors are considered to be 18-24 months
of age. When one or both middle (I 2) incisors erupt, the animal is considered to be 24-30
months of age.
Cattle that have the middle (I 2) incisor (or incisors) erupted are in the 24-30-month age range.
However, FSIS, as written in FSIS Notice 5-04, is using a conservative approach and is
determining that cattle with eruption of at least one of the second set of permanent incisors (I 2)
are 30 months of age or older.
The eruption of the lateral (I 3 or second intermediate) incisor (or incisors) indicates that the
animal has reached 36 months of age. The eruption of the corner (I 4) incisor (or incisors)
indicates that the animal has reached at least 42 months of age.
For more information visit: http://www.fsis.usda.gov/OFO/TSC/bse_information.htm
