998 Veterinary Obstetrics 



quarters, and bringing into jeopardy the life of the animal. This 

 is especially true of such operations, when 2, 3 or all the teats are 

 affected and the number of operations required renders serious 

 mammitis well nigh inevitable. After all the danger to the 

 animal, the outlook for any definite improvement is virtually 

 hopeless. 



Should the veterinarian decide to operate, the essential object 

 to be attained consists of a dilation of the teat canal, or of the 

 communication between the teat cistern below and the milk 

 canals above. Any and all operations having such an end in 

 view require the strictest possible asepsis. The hands of the 

 operator, the teat and the instruments must be scrupulously clean, 

 and the operations must be carried out without introducing into 

 the teat any form of infection or irritant. Even after an opera- 

 tion has been successfully performed, from the standpoint of 

 asepsis, it is still a difficult problem to so instruct a caretaker that 

 he will use the necessary precautions to maintain an aseptic 

 condition in the part during the process of healing. Various 

 methods for overcoming the stricture or atresia have been sug- 

 gested, differing in detail, and belonging essentially to two classes 

 — the bloodless and the bloody dilations. 



The dilation of the narrowed canal, without the division of the 

 tissues, is attempted by means of bougies or sounds. This 

 method can only be applied in those cases where the lumen of 

 the canal is narrowed, but not completely closed. Some advise 

 the introduction of a piece of catgut about two to three cm. in 

 length, bearing a head at the distal end, which will prevent it 

 from slipping entirely into the teat. When this is introduced 

 through the constricted portion, it swells by absorbing surround- 

 ing moisture, and gradually dilates the constricted part. It may 

 be inserted just after one milking, and remain in position until 

 the next. Others advise the repeated insertion or prolonged re- 

 tention of metallic teat sounds or bougies like b. c, Fig. 143. 



Other forms of bougies have been suggested, such as one con- 

 sisting of pure gum, which exerts gradual pressure upon the part 

 and brings about dilation. 



These palliative measures have generally proven unsatisfactory, 

 being accompanied by very decided danger, without any corre- 

 sponding probability of permanent benefit. 



