CONTROL OF BACILLARY WHITE DIARRHCEA, 



1920-1921. 



BY G. E. GAGE. 



PREVIOUS WORK. 



The first report of any work on this subject in Massachusetts was pubHshed as 

 Bulletin No. 148, under the title "On the Diagnosis of Infection with Bacterium Pul- 

 lorum in the Domestic Fowl." In this paper were presented experiments to determine 

 the value of testing eggs from suspected hens as a method of diagnosis. It was found 

 that the elimination of the organism from the ovary was so irregular that it would be 

 impossible to make a diagnosis within a short time. The results of the apphcation of 

 the macroscopic agglutination test were also presented. This has proved to be, under 

 the proper conditions of the test, a good laboratory method for the detection of adult 

 hens which are harboring, or have harbored, Bacterium 'pullorum. 



The second pubhcation was issued in 1915, under the title "Bacillary White Diar- 

 rhoea {Bacterium Pullorum Infection) in Young Chicks in Massachusetts." At that 

 time it was found that in all districts of Massachusetts there was a heavy infection 

 among adult breeding birds, and that it was generally scattered over the State. The 

 paper was published at that time to make poultrymen aware of the prevalence of the 

 disease and to enlist their interest and willingness to co-operate in every way to ehm- 

 inate it. 



Ovarian infection has been conclusively demonstrated and it is known that chicks 

 which survive frequently become permanent bacillus carriers, the ovary being the 

 important seat of infection. Eggs from such carriers often harbor the organism of 

 the disease in the yolk. Chicks that develop in infected eggs become in turn infected 

 and may have the disease at time of hatching. The disease may be transmitted to 

 normal chicks through infected droppings, thus producing an epidemic, and the cycle 

 of infection is completed. 



Since it has been definitely proved that Bactervmn 'pullorum is the causative factor 

 in this disease, and that eggs may gain infection from infected ovaries, the infected 

 individual must be sought and eliminated from the breeding flock. This is the only real 

 basis for improvement. The macroscopic agglutination test has aided in this direc- 

 tion, and the results of our control tests to-day depend upon the application of it to 

 the work of epidemiology in the field. Although we have found a very widely dis- 

 tributed infection, we have never tried to discourage present or prospective poultry 

 raisers, but with our control problem under way it is hoped to encourage greater 

 effort in the industry. 



