170 



VETERINARY BACTERIOLOGY 



Preparation 

 present in a 



of Bacterial Emulsion. The organisms must be 

 perfectly homogeneous suspension. With most 

 organisms a twenty-four-hour slant agar 

 culture may be used, the growth scraped 

 off into sterile physiological salt solution, 

 triturated, and diluted until it shows only 

 a faint opalescence. Filtration is sometimes 

 necessary. This technic must be varied 

 somewhat for different organisms. 



Preparation of Serum. Both normal 

 serum and serum from the animal to be 

 tested are secured by bleeding, allowing 

 the blood to clot, centrifuging, and taking 

 off the serum with a pipette and transferring 

 to a small tube. Before use, the serum is 

 sometimes diluted usually ten times. 











Fig. 80. Opsonizing 

 pipette containing the 

 leukocytes, bacteria, 

 and serum (Miller). Fig. 81. Opsonic incubator (Miller). 



Technic of Test. A capillary pipette with a fine bore is prepared 

 from glass tubing, and a mark is made a short distance, usually 



