CHAPTER XXXIX 



EXPERIMENTAL MODIFICATION OF BIRD 

 MALARIA INFECTIONS 



I. BY CHANGING THE SUGAR CONTENT OF THE 



BLOOD 



By 



M. S. MacDougall 

 Agnes Scott College 



II. BY CHANGE IN ENVIRONMENT 



By 



G. H. Boyd 

 The University of Georgia 



I. CHANGING THE SUGAR CONTENT OF THE BLOOD 



Preliminary statement. Bass (1912) in his effort to cultivate the 

 organism of human malaria on artificial media, and others who 

 have repeated his w^ork, found that the addition of sugar to the 

 culture medium w^as necessary for success. Bass and Johns (1913) 

 reported the cultivation of the organism of human malaria in 

 the blood of a diabetic without the addition of sugar. It has also 

 been found that certain provocatives which bring on relapse in 

 bird malaria, e.g., epinephrin, exposure, etc., increase the sugar 

 content of the blood. In an effort to study relapse (Hegner and 

 MacDougall, 1926), it seemed worth while to observe the effects 

 of changing the sugar content of the blood of the birds, especially 

 during the period of sporulation. 



Materials and methods. Infection with the Hartman strain of 

 bird malaria, Plasmodium cathemeriuui, was transferred from one 

 female canary to another by direct l)l()()d inoculation, injections of 



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