SEXUAL APPARATUS. 195 



form should be determined. Finally, milk every teat in order 

 to determine the ease with which the fluid can be drawn, no- 

 tice the size of the stream and the character of the milk, 

 whether it is c 1 o 1 1 e d or bloody: A microscopical ex- 

 amination of abnormal milk is not 

 necessary but may be of value in 

 some cases. To determine wheth- 

 er a cow is "fresh" a microscopical 

 examination of the milk for the col- 

 ostrum bodies or corpuscles must 

 be made. 



Fig. 50. Colostral Milk. 



Harpooning the udder according to Ostertag. The 



operation may be performed on the standing animal, but bet- 

 ter results can be obtained if the animal is cast and secured. 



\\'ash the field of operation with soap and water, rinse 

 with 2 per cent, lysol solution, 'following this with 50 per 

 cent, alcohol. With hooked forceps grasp the skin overlying 

 the suspicious area in the udder and at the fold thus pro- 

 duced incise the skin and underlying facia with scissors, grasp 

 the tissues with the thumb and index finger of the left hand 

 and insert the harpoon with the right. When the suspected 

 tissue has been reached give the harpoon a half turn and 

 withdraw it quickly. The cutaneous wound is closed \vith 

 artery forceps which are allowed to remain ten minutes, 

 whereupon the wound is sealed with iodoformcollodion. 



Cows thus treated will give bloody milk for a few days, 

 but if carefully performed the operation is not dangerous.' 



Tubercles, if contained in tissue thus removed, can usual- 

 ly be recognized with the aid of a simple lens. If the exam- 

 ination gives negative results it is advisable to repeat the op- 

 eration. Tubercle bacilli can always be demonstrated in 

 the tubercles. 



In this method a positive diagnosis alone is of anv value. 

 AVe can not rely upon negative results. This method is of 



