CHAPTER XIII. 



PROJECTING TEETH IN HORSES, SHEEP AND 

 PIGS. 



THEIR CAUSE, RESULTS AND TREATMENT. 



There seems to be a difference of opinion among 

 the various authors in regard to the length of time 

 permanent teeth continue to grow; some maintaining 

 that the growth of the tooth is completed by the 

 sixth or seventh year, others by the tenth or twelfth 

 year, while some contend that the tooth of a horse 

 grows for a much longer period. 



Clark, " Horse Teeth," page 73, says: "They, 

 * permanent teeth attain their growth more slowly 

 than the temporary, and a healthy tooth continues to 

 grow throughout life. The growth offsets the wear, 

 the wear the growth. 



If we carefully examine the above statement we 

 can not conclude otherwise than that the tooth retains 

 its length throughout life, for if "the growth off. 

 sets the wear, and the wear the growth," then it 

 must necessarily follow that one end of the tooth 

 is reinforced as fast as the other is cut away by attri- 

 tion. This theory does not hold true in actual prac- 



* Italics mine. 



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