Donkeys have 12 cutting teeth, 6 upper and 6 lower. The pair in the middle is called front teeth, the pair next to front teeth is called middle teeth, and the pair on both sides is called horn teeth.
1-The black fossa of deciduous teeth under 5 years old disappeared.
At the age of 2, the middle teeth of the lower breast became black and fell off.
At the age of 2-5, the black fossa of the lower horn of deciduous teeth disappeared.
At the age of 3, the permanent lower incisors appeared. The villagers call it "three-year-old teeth" and "thousand-day teeth".
At the age of 4, the middle teeth of permanent teeth appeared. The fellow villager is called "4 years old and 4 teeth".
At the age of 5, permanent angle teeth appeared (but the front edge was very thin). The hometown is called "five-year-old tooth". At this time, the donkey began to have canine teeth.
The 6-year-old horn teeth have come out. The villagers are all called "six years old and seven mouths". However, the angle teeth are only crescent-shaped, and the lower incisors begin to appear filamentous dental stars.
At the age of 7, filamentous dental stars appeared in the middle teeth; The black fossa of the lower incisors is oblate with obvious edges and corners. The villagers call it "seven squares and eight circles", which means that the black nest is square at the age of 7 and round at the age of 8.
At the age of 9, the black pit of the lower incisors became as small as mung beans, and the teeth were long and rectangular; The middle tooth star is horseshoe-shaped; The trailing edge of the horn tooth begins to form.
When 10 ~ 1 1 year old, the black pit of the lower incisors becomes smaller and the incisors become rectangular.
12 ~ 13 years old, the depth of the black pit of the lower incisors is shallow, only 1 mm, and the villagers have the saying that "biting down the middle bend is 12 or 13 years old". At this time, a pair of root flowers appeared on the upper incisors (that is, the exposed part of the root increased in Yellowstone ash, called A yellow).
14 ~ 15 years old, the black pits of front teeth and middle teeth disappear, and the horn teeth are round. The villagers call it "fifteen-year round tooth", which is quite accurate.
16-year-old tooth star and lower incisors have rounded chewing surfaces.
17 ~ 19 years old, the chewing surface developed into a vertical ellipse, and the tooth star was a regular circle.
The tooth star of 20 ~ 23 years old is located in the center like a chestnut; The chewing surface is vertical oval; Yellow teeth; Pale gums.
Extended data donkey is the domesticated offspring of African wild donkey and one of the important domestic animals in the world. China has a vast territory and a long history of raising donkeys. According to the body shape, it can be divided into three types: the big donkey is related to the middle donkey and the Biyang donkey, and the body height is above 130 cm; The medium-sized donkey is Liaoning donkey, and its height is 1 10 ~ 130 cm.
Donkey, mostly produced in North China, Gansu and Xinjiang, is 85 ~ 1 10 cm tall. Donkeys are shaped like horses, mostly grayish brown and not dignified. It has a big head and long ears, a slightly narrow chest, thin limbs and a short trunk, so its height and length are roughly the same, and it is square.
Donkeys have thin neck skin, small and solid hooves, strong physique and strong resistance. Donkeys are strong, resistant to extensive farming, not easy to get sick, and have the advantages of docile temperament, diligence and obedience.
CCTV- Know how to judge the age from the donkey's teeth
Baidu encyclopedia-donkey