Agglutination. 



Normal blood serum agglutinates it in dilutions of 1-5. 

 Serum from sick birds agglutinates it completely in dilu- 

 tions of 1-20 and partially in dilutions of 1-60. 



Complement fixation test. 



Using an extract of this organism as an antigen did not 



produce fixation of the complement. 



Antigen was prepared as follows: Organism was 

 grown on agar and emulsion made in .85% NcCl solu- 

 tion heated for one hour at 60° C. and shaken for 36 

 hours at 480 strokes per minute. A 1-20 dilution of the 

 extract of the organism did not prevent hemolysis. A 

 1-40 dilution of the antigen and positive serum in 

 amounts varying from .03 cc. to .5 cc. was used for the 

 test. 



Pathogenicity: Healthy young chickens were inoculated as 

 follows : 



(1) Two inoculated subcutaneously on the comb. 



(2) Two inoculated submucously in the oral cavity. 



(3) Two inoculated intravenously. 



(4) Two inoculated intraperitoneally. 



(5) Two inoculated by scarifying the wattles. 



In birds Nos. 2 and 5, local lesions appeared on the second 

 day, lasting an average of five days, and resulting in complete 

 recovery without producing the typical diseases, i. e., there 

 were no general symptoms. 



Organism No. 2. A small motile bacillus resembling a 

 diplococcus. 



Stains by all ordinary stains, gram negative. 



Broth: grows in small chains. 



Agar: moist, transparent grayish growth. 



Blood serum: not digested. 



Gelatin: liquifies slightly. 



Potatoes: grayish growth. 



Milk: coagulates with acid production. 



Sucrose-broth: acid and gas production. 



Dextrose-broth: acid and no gas. 



Lactose: acid (slight) and no gas. 



Negative results on agglutination and complement fixa- 

 tion test. 



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