62 a EXPERBIENT STATION. [Jan. 



birds. These birds belonged to more than 103 different owners 

 of poultry in 70 different cities and towns of the State. The 

 average percentage of reactors among something like 26,000 

 birds tested since the routine test was started in 1915 has been 

 found to be 13.5 per cent. It is gratifying to note, in the case 

 of the second application of the test to flocks previously tested, 

 in which more than half the birds gave a strong reaction, that 

 the disease bacillarv white diarrha^a has been eradicated. 



2. Investigations relative to Bacterium Pullorum 



Infection. 



The investigations relative to Bacterium indlornm infection 

 have been in charge of Dr. G. E. Gage. Regarding these 

 studies he reports, under date of November 22, as follows : — 



The work bearing on the specificity of Bacterium puHonim 

 antibodies, with special reference to the agglutinins, has been 

 completed, and will be published in the near future. The re- 

 sults furnish data for a comparison of the B. imUoruin antibodies 

 with those of the B. coJi-B. ti/phi-B. dysenterae group of agglu- 

 tinins, and also data for discussion concerning the diagnostic 

 value of the agglutination test. 



The problem concerning the production of toxin by Bacterium 

 pullorum has received most of the time at my disposal for ex- 

 periment station work during the past year. This has proven 

 a very difficult task in that the determination of a uniform 

 grade of toxin has been hard to obtain. Data, however, are at 

 hand which are of interest in Bacterium pullorum studies, and 

 will be ready for publication some time this fall. They will be 

 published under some such heading as "The Toxicity of 

 B. pullorum Products." 



The investigation concerning the production of antibodies, 

 with special reference to the potency and rate of production, 

 started in August, 1916, is now being continued as outlined at 

 that time. At the present time a large number of birds, de- 

 scendants of especially immunized individuals, are on experi- 

 ment. Attempts are being made to study the progeny this year 

 to determine potency and rate factors of the agglutinins elab- 

 orated in such birds descended from stock known to have defi- 



