DENTITION AND DENTAL DISEASES 



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364. Incisors. — Between one year and nine months and two years and 

 three months the two central incisors are replaced by permanent 

 teeth ; at two years and three months to two years and six months the 

 two middle lateral incisors are cast, and the animal has four broad 

 teeth ; at three years old six permanent teeth are seen ; and at about 

 three years and three months the corner or canine milk teeth are shed, 

 and eight broad teeth are in view. The permanent teeth are very 

 much larger and darker than the milk teeth, which are very white, 

 and are thus readily distinguished. 



365. The following illustration shows at what age the incisor 

 milk teeth of cattle are cast and replaced by permanents : 



Fig. 13. — Permanent Incisors of the Cow. 



1. Centrals, 1 year 9 months to 2 years 3 months. 



2. Middle laterals, 2 years 3 months to 2 years 6 months. 



3. Laterals, 2 years 6 months to 3 years. 



4. Corners, or canines, 3 years to 3 years 3 months. 



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//JVt 







366. The crowns or wearing surfaces of the molar teeth of 

 cattle are very unlike those of the horse, having sharp elevations 

 and depressions, resembling the teeth of flesh-eating animals, and 

 are well suited for tearing down rough fibrous grass, but are not 

 adapted for grinding oats or other grain, the cow being a true 

 herbivorous animal. 



