BLEEDING CATTLE. 



H9 



stick, or failing this, from the edge of the right hand, drives the 

 fleam into the vein. The fleam must be held exactly at right angles 

 to the skin over the highest prominence of the vein, otherwise the 

 vessel will be opened on one side or the instrument will slip 

 past it. 



Dieckerhoff and Caspar recommended a special trocar and cannula 

 for bleeding. As this instrument had been used for some years for 

 intra- venous administration of drugs, it occurred to them that it 

 might be equally useful for withdrawing blood, especially where it 

 was desirable to shield the withdrawn blood against contamination, 

 as in preparing protective serum. The cannula has the great advan- 

 tage over the fleam that it can be inserted several times at the same 

 place. In operating, the vein is raised, the skin divided, and the 

 vein exposed. The 



operator, standing on 1||k,, y^ 



the animal's near side, \ ml 



then thrusts the 

 cannula, carrying its 

 shield, steadily into 

 the vein for a distance 

 of three or four inches, 

 when bleeding follows. 

 Some dexterity is re- 

 quired, but the method 

 is particularly useful 

 for laboratory work, 

 and avoids almost all 

 the risks formerly ap- 

 pertaining to phlebotomy of the jugular. When the necessary amount 

 of blood has been abstracted, a blunt trocar is inserted into the 

 cannula to prevent air entering the vein, and the combined instru- 

 ment withdrawn. The wound is dressed antiseptically and closed 

 with a single suture, or may be left open. 



In cattle the jugular vein is also opened. The animal's head is 

 raised by grasping the horns and the eyes covered. The hair is 

 removed from the seat of operation, the bleeding cord previously 

 mentioned adjusted, and the vessel opened just above the point 

 of compression by means of the fleam. The operator stands as in 

 bleeding a horse. In small cattle one may even stand on the side 

 opposite to that of operation and lean over the animal. This method 

 has the advantage that the operator cannot well be struck by the 

 animal when, as occasionally happens, it kicks in a forward direction. 



Fig. 207.— Bleeding with the fleam and blood-stick. 



