24 METHODS <»K CASTING ANIMALS. 



If, however, any serious operation is required four hobbles are 

 affixed to the feet, the winch handles are turned (both together) 

 until the horse's feet begin to leave the ground, when the safety 

 chocks are cast off, permitting the apparatus to revolve, and 

 depositing the horse without shock or pain in a horizontal position. 

 The animal may be placed at any degree of inclination to the 

 horizontal, and its position on the table is extremely safe. Broken 

 back has never occurred within the writer's experience. 



Methods of Casting. A permanent bed is usually prepared with 

 six to eight inches of dry spent tan bark covered with a thick layer 

 of short cut straw. Many practitioners still prefer the straw bed 

 to mattresses, because it is softer and because it can be removed, 

 and fresh straw supplied after each operation, whilst the mattress 

 must be thoroughly cleansed and disinfected. It has also the 

 advantage of being cheap, as clean straw is readily obtainable and 

 may afterwards be used for bedding, whilst it is a difficult matter 

 for veterinary surgeons in country practice to convey a mattress 

 from place to place. Nevertheless, straw makes a very bad bed 

 for aseptic operations, and wherever possible it should be replaced 

 by a mattress covered with tarpaulin, or by a proper operating table, 

 though some of the disadvantages of the straw bed may be over- 

 come by covering it with a large tarpaulin before casting the horse. 

 Even so high an authority, however, as Bayer adhered to the straw 

 bed, preferring it partly, because he had to teach students who, in 

 practice, would be unable to afford an operating table, and partly 

 because of the success attained in his own clinique. In support of 

 his recommendation he adduced a long series of cases in which the 

 wounds left by the removal of shoulder abscesses, necrotic lateral 

 cartilages, etc., healed by primary intention after suturing. 



To prevent internal injuries, like rupture of abdominal viscera. 

 the animal should fast or only receive light food for several hours 

 before operation, though, as already mentioned, this precaution is 

 not absolutely indispensable. Should it be impracticable to perform 

 the operation in the standing posture the operator should throw 

 the horse on a sloping bed or bank of straw, so that the animal may 

 fall as easily as possible. One of the simplest methods of casting 

 is that shown in Fig. 41. It is especially useful for young animals 

 or those difficult to approach, in which ordinary hobbles cannot 

 be used. It is also useful where the hind legs have to be drawn 

 downwards on either side of the body for operations in the dorsal 

 position, inasmuch as the application and removal of hobbles are 

 thereby rendered unnecessary. In case of need a cart rope may be 



