12 



LABORATORY EQUIPMENT 



SUBCUTANEOUS inoculation is the simplest of all methods. 

 A fold of skin is elevated between the thumb and index finger 

 * tne ^ e ^ nan< ^ an( ^ tne needle plunged into the subcutaneous 

 tissue. In rabbits and guinea-pigs the skin of the back or 

 abdomen is chosen, as the subcutaneous tissue here is not tense. In goats, 

 sheep, and horses the skin of the neck and shoulder region is preferred. 



Sub- 

 cutaneous 

 Injection. 



FIG. 5. Removal of peritoneal exudate. Guinea-pig held in Friedberger's position. (Original.') 



The skin of the back and abdomen is to be avoided because following the 

 injection edema frequently arises, which may extend to the lower extrem- 

 ities and thus interfere with locomotion. 



If abscesses arise after subcutaneous injection, they should be opened, 

 washed out with lysol solution and dressed with iodoform gauze. 



The Methods of Obtaining and Preserving Serum. 



Venesection or venous puncture is the method best adapted for obtain- 

 ing blood from animals. The veins employed for that purpose are those 



