METHODS OV RESTRAINT AND COMMON OPERATIONS 191 



plantar neurotomy, for the relief of navicular or ringbone lameness, 

 or other non-infectious, painful conditions below the fetlock; 

 median neurotomy, to relieve lameness due to disease of the fore 

 limb, so located that it cannot be overcome by plantar neurotomy; 

 sciatic and anterior tibial neurotomies, for the destruction of sen- 

 sation in the hock and parts distal thereto to relieve otherwise 

 incurable spavin lameness and diseases of the tendons. 



TRACHEOTOMY 



Tracheotomy is an operation to provide a direct entrance for 

 air into the trachea. It is performed for the following purposes : 



To avert suffocation threatened by swelHngs or other obstruc- 

 tions in the upper air-passages; to restore to usefulness animals 

 that have difliculty in breathing produced by stenosis of the upper 

 air-passages; and to remove foreign bodies from the trachea. 



The operation is best performed on the standing animal with 

 the head extended. A portion of two adjoining tracheal rings is 

 removed. There is then inserted a special trachea tube, with a 

 fine wire-gauze covering to prevent dust particles in the air from 

 passing through. This tube is to be removed and cleansed daily 

 as long as its use is necessary. 



ARTIFICIAL INSEMINATION 



The impregnator is used in horse-breeding as a practical and 

 satisfactory means of breeding mares that have been difficult or 

 even impossible to breed by direct service. As a means of breeding 

 several mares at one service of the stallion, it has extended his use 

 to more mares than would otherwise be possible. 



In Bulletin 93 of the Oklahoma Experiment Station, Dr. L. L. 

 Lewis discusses the various forms of instruments employed for 

 artificial insemination and their methods of use. He emphasizes 

 the necessity of keeping all instruments scrupulously clean. As 

 the sperm cells are very abundant in the semen, it is not necessary 

 to place a large amount in the womb. Experiments show that con- 

 tact with the air seems to have little effect upon the vitality of the 

 sperm cells. Direct sunUght is injurious to them, and semen left 

 in the sun soon loses its vitality. The life of the cells is short even 

 when protected, as in normal copulation, so an effort must be made 

 to introduce the semen into the womb without unnecessary ex- 

 posure or delay. 



