APPARENT RECOVERY OF A HEN INFECTED WITH 

 BACILLARY WHITE DIARRHEA 



As Determined by the Macroscopic Agglutination Test 



GEORGE D. HORTON 



Department of Bacteriology, Missouri State Poultry Experiment Station 



* Received for publication, September 18, 1916 



The following note deals with the case of a Bantam hen which 

 at one time (1914), gave a positive agglutination test and at a 

 later date (1916) gave a negative reaction. 



The method of testing was essentially that devised by Jones. 

 A polyvalent test fluid with proper controls was used. 



The Bantam was one of a flock of several hundred birds of 

 which approximately 65 per cent were infected. The bird was 

 tested first in December, 1914; the reaction was very marked 

 within 24 hours. In the fall of 1915 the test was applied again; 

 the reaction was faint after 72 hours. During 1916 two tests 

 were made, both of which were negative even after 72 hours. 



That reacting fowls may lay eggs the yolks of which harbor 

 the infective organism, B. pullorum, has been demonstrated by 

 Rettger, Gage and others. The infection in this case was un- 

 doubtedly of ovarian origin because of the finding and isolation 

 of pure cultures of B. pullorum (the infective agent in the bacil- 

 lary form of white diarrhea) from two unhatched eggs of a 

 sitting of eggs laid by this Bantam in 1915. 



In view of the above observation however, we may ask, — ^is 

 it not possible for an infected fowl to free herself of infection? 

 or, is she once and for all time a bacillus carrier? 



Although this single instance furnishes but limited evidence 

 it suggests the possibility of recovery, or the throwing off of 

 ovarian infection. 



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