18 DISEASES OF CATTLE. 



solution each time. If, however, the salivation depends on the 

 presence of a thorn, splinter of wood, or any other foreign substance 

 embedded in the cheek or tongue, remove the offending object and 

 wash the mouth occasionally with a weak solution (2 per cent) of car- 

 bolic acid and tepid water. When salivation is produced by mercu- 

 rial poisoning or by the foot-and-mouth disease, the treatment appro- 

 priate to those general conditions of the system, as well as the local 

 treatment, must be applied. 



IRREGULARITIES OP THE TEETH. 



Irregularities of the teeth may be occasioned by the unequal wear- 

 ing of some of the teeth or by some of the incisors being broken, which 

 may happen when cattle are pastured on sandy or gravelly soil. The 

 molar teeth may also show irregular wear from similar causes, or from 

 a disease or malformation of the jaw. Their edges may become sharp, 

 or it may happen that a molar tooth has been accidentally factured. 

 It may also occur that a supernumerary tooth has developed in an 

 unusual position, and that it interferes with the natural and regular 

 mastication of the food. 



Treatment. — The mouth may be examined by grasping the animal's 

 tongue with one hand and partially withdrawing it from the mouth, 

 so as to expose the incisor and molar teeth to inspection. When it 

 is desired, however, to examine the molar teeth with the fingers, so as 

 to obtain a more precise idea of their condition, an instrument like 

 the balling iron which is used for the horse should be introduced into 

 the mouth, so as to separate the jaws and keep them apart while the 

 examination is being made. Any sharp edges of the molars must be 

 removed by the tooth rasp, such as is used for horses. Any super- 

 numerary tooth which interferes with mastication or any tooth which 

 is fractured or loose should be extracted. In performing such oper- 

 ations it is desirable to throw, or cast, the animal, and to have its 

 head held securely, so as to enable the operator to do what is neces- 

 sary without difficulty. 



CARIES OR DECAY OP THE TEETH. 



The presence of caries may be suspected if the mouth exhales a bad 

 odor and if the animal occasionally stops during mastication as if it 

 were in pain. The existence of caries in a molar tooth may be ascer- 

 tained by examining the mouth in the manner already described. If 

 one of the molars is found to be carious, it should be extracted 

 When the crown of the tooth has been destroyed and only the stunm 

 or root is left, extraction will be impracticable. In such cases it is 

 best to sell the animal to the butcher unless it have special value in 

 which case the root stumps may be removed by a veterinarian by the 

 operation of trephining. 



