狗狗年龄的鉴定
有关犬的年龄鉴定，以犬的牙齿生长状况、齿峰与齿的磨损程度，以及牙齿的颜色等为判断犬年龄的重要依据。例如，成年犬的牙齿42枚，其犬齿全部是短齿冠形，上颌的第1与第2门齿齿冠为三尖峰形，即中央为大尖峰，两侧的为小尖峰，其余门齿各有大小两个尖峰，犬齿呈弯曲的圆锥形，尖端锋利，是攻击与自卫的武器。前臼齿为三峰形，后臼齿为多峰形。
幼犬的乳齿，呈白色，齿细而尖，全部长齐，共计28枚。
幼犬出生20天左右即长出乳齿，4~6周龄，乳门齿长齐；2个月龄，28枚乳齿全部长齐。2~4个月龄，更换第一乳门齿。5~6月龄，更换第2~3乳门齿及乳犬齿。8个月龄以后，全部更换成恒齿。
1岁犬，恒齿长齐，洁白光亮，门齿上有尖突。
1岁半犬，下颌的第一门齿大尖峰磨损至与小尖峰平齐。
2岁半犬，下颌的第二门齿尖峰磨灭。
3岁半犬，上颌的第一门齿尖峰磨灭。
4岁半犬，上颌的第二门齿尖峰磨灭。
5岁犬，下颌第三门齿尖峰稍磨灭，而下颌的第一、二门齿磨成矩形面。
6岁犬，下颌第三门齿的尖峰已磨灭，犬齿磨成钝圆。
7岁犬，下颌第三门齿磨损至齿根部，磨损面呈纵椭圆形。
8岁犬，下颌第一门齿磨损面向前方倾斜。
10岁犬，上颌第一门齿及下颌第二门齿磨损面呈纵椭圆形。
16岁犬，门齿脱落，犬齿不全
Identification of the age of the dog
Age determination about the dog to the dog's teeth growth conditions, the degree of tooth wear and tooth peaks, as well as the color of the teeth to determine the age of an important basis for the dog. For example, the adult dog teeth 42, which are all short canine tooth crown, the first maxillary incisor crown and a second for three spike-shaped, that is central to a large spike, small spikes on both sides, the rest of the incisors have the size of the two spikes, fangs curved conical tip sharp attack and self-defense weapons. Premolars for three peaks form, after the molars of multimodality.
Puppies primary teeth, white, thin and sharp teeth, all long Qi, totaling 28.
Puppies born 20 days or so that primary teeth grow 4 to 6 weeks old, milk incisors longer homogeneous; 2 months of age, all 28 primary teeth longer homogeneous. 2 to 4 months of age, the replacement of the first milk incisors. 5 to 6 months of age, the replacement of 2 to 3 breast milk incisors and canines. After eight months of age, all replaced with permanent teeth.
1-year-old dog, permanent teeth longer homogeneous, white and bright, with the incisor cusp.
A year and a half dog, the first big spike mandibular incisors with small spikes worn to flush.
2-year-old half-dog, second incisor jaw spikes forgotten.
3-year-old half-dog, the first maxillary incisors spikes obliterated.
4-year-old half-dog, maxillary incisors second peak obliterated.
5-year-old dog, mandibular third incisor spikes slightly forgotten, and the mandibular first and second incisors ground into rectangular faces.
6-year-old dog, mandibular third incisor spikes have been obliterated, canines ground obtuse.
7-year-old dog, mandibular third incisor teeth worn to the roots, wear-section vertical oval.
8-year-old dog, facing the front of the first mandibular incisors wear tilt.
10-year-old dog, maxillary and mandibular incisors first appear before the second incisor wear vertical oval.
16-year-old dog, shedding incisors, canines incomplete
狗狗年齡的鑑定
有關犬的年齡鑑定，以犬的牙齒生長狀況、齒峰與齒的磨損程度，以及牙齒的顏色等為判斷犬年齡的重要依據。例如，成年犬的牙齒42枚，其犬齒全部是短齒冠形，上頜的第1與第2門齒齒冠為三尖峰形，即中央為大尖峰，兩側的為小尖峰，其餘門齒各有大小兩個尖峰，犬齒呈彎曲的圓錐形，尖端鋒利，是攻擊與自衛的武器。前臼齒為三峰形，後臼齒為多峰形。
幼犬的乳齒，呈白色，齒細而尖，全部長齊，共計28枚。
幼犬出生20天左右即長出乳齒，4~6週齡，乳門齒長齊；2個月齡，28枚乳齒全部長齊。 2~4個月齡，更換第一乳門齒。 5~6月齡，更換第2~3乳門齒及乳犬齒。 8個月齡以後，全部更換成恆齒。
1歲犬，恆齒長齊，潔白光亮，門齒上有尖突。
1歲半犬，下頜的第一門齒大尖峰磨損至與小尖峰平齊。
2歲半犬，下頜的第二門齒尖峰磨滅。
3歲半犬，上頜的第一門齒尖峰磨滅。
4歲半犬，上頜的第二門齒尖峰磨滅。
5歲犬，下頜第三門齒尖峰稍磨滅，而下頜的第一、二門齒磨成矩形面。
6歲犬，下頜第三門齒的尖峰已磨滅，犬齒磨成鈍圓。
7歲犬，下頜第三門齒磨損至齒根部，磨損面呈縱橢圓形。
8歲犬，下頜第一門齒磨損面向前方傾斜。
10歲犬，上頜第一門齒及下頜第二門齒磨損面呈縱橢圓形。
16歲犬，門齒脫落，犬齒不全