DERANQEMEJTTS OF THE TEETH. 299 



Ieeegulaeities of Growth. — This includes a survey of 

 the teeth, under two distinct periods of the life of the animal. 

 The first of these is tliat comprised in the early life of the 

 horse — a period including the time from the birth of the animal 

 until the time at which all the permanent teeth are either com- 

 pletely developed, or in a state rapidly approaching that of 

 complete development. This period may be said to terminate 

 with the end of the 5th year of the age ; while the second 

 period commences with the completion of this year, and con- 

 tinues until the death of the animal, be that sooner or later, as 

 accident or design may determine. 



FiEST Peeiod. — The principal abnormalities of the teeth, 

 during this period, arise from irregularities in the growth and 

 development of the new and permanent teeth, and in the pro- 

 cess which attends the shedding of the temporary or milk 

 ones. 



The mouth of the gelding, when five years of age, contains 

 forty permanent teeth, At first, twenty-four of this number 

 (viz., twelve incisors and twelve molars) are developed as tem- 

 porary organs ; but these, at the period named, have all 

 disappeared, and have been replaced by teeth of a permanent 

 class, and of a larger growth. The remaining sixteen of the 

 forty are developed as permanent organs in the first instance. 

 Now the development and shedding of the temporary teeth, 

 and the appearance and the development of the permanent 

 ones, are periods (for the process is both slow and gradual) 

 productive of more or less disturbance to the general health of 

 all young colts and fillies. 



Sometimes the permanent molars are delayed in their 

 appearance, and sometimes the temporary molars and incisors 

 are not cast so readily as usual with young animals in general. 

 The first step to be taken with those which may not feed well, 



