All domestic animals have two successive sets of teeth. Deciduous teeth, or milk teeth, are the first set of teeth in young animals. These are replaced by a permanent set of teeth as animals age.
In an anatomic tooth-identification system, permanent teeth are designated as incisor (I), canine (C), premolar (P), and molar (M); deciduous teeth are designated as Di, Dc, and Dp. The canine tooth of domestic ruminants has commonly been counted as a fourth incisor.
The dental formulas are shown below.
Goats, as with other ruminant animals, lack upper incisors. Instead, a hard dental pad on the frontal part of the upper jaw serves in place of teeth. Each formula represents the number of teeth a goat has on one side of its upper and lower jaws; the number is multiplied by two for the total number of teeth in the mouth. The upper jaw teeth number is represented by the upper number in the fraction, and the lower jaw teeth number is represented by the lower number in the fraction.
Goat Deciduous Teeth Dental Formula: 2(Di 0/4; Dc 0/0; Dp 3/3) = 20
Goat Permanent Teeth Dental Formula: 2(I0/4; C0/0; P3/3; M3/3)= 32
In kid goats, the first pair of milk teeth incisors occurs at birth to 1 week of age. The second pair of milk teeth incisors erupts at one to 2 weeks of age, the third pair at 2 to 3 weeks of age, and the fourth pair of milk incisors appears at 3 to 4 weeks of age.
The sequence for the eruption of permanent incisors is 1 to 1.5 years of age for the first pair of incisors, 1.5 to 2 years for the second pair, 2.5 to 3 years for the third, and 3.5 to 4 for the fourth pair of incisors. A full mouth of permanent teeth is in place by the time the goat reaches 4 years of age. Estimating age in goats older than 4 years is achieved by assessing the amount of wear that has occurred on the teeth, which can vary with the degree of dietary abrasiveness (see Teeth and Age of the Goat and Judging Goat Age by Teeth).