406 STATE BOARD OF AGRICULTURE. 



FOREWORD. 



Technical Bulletin No. 8. 

 BY WARD GILTNER. 



The ])resent bulletin continues the work published in Technical Bul- 

 letin No. 3 of this station, giving, however, more extensively and defi- 

 nitely the agglutinative relation of the blood-serum secured from normal, 

 virus, immunized, and hyperimmunized pigs to B. cJtolerae suis. While 

 the work established the fact that no dependence may be placed upon 

 the degree of agglutination to indicate the potency of serum, it has 

 been the means of providing many interesting and useful data as well 

 as suggestions. These suggestions will be the basis of further investiga- 

 tions. 



It becomes more and more apparent that, notwithstanding the value 

 and utility of the Dorset-Niles serum as it is n\oio manufactured, the 

 problems concerning the practical manufacture and application call for 

 renewed effort. A more intimate knowledge of the processes involved 

 becomes essential to the most intelligent production and use. A solution 

 can be found only in a study of the filterable virus, B. cholerae suis, 

 and the organism of the pig as they are associated in this disease, hog 

 cholera. 



CHARLES E. MARSHALL. 



