440 STATE BOARD OF AGRICULTURE. 



hog cholera?" Our work furnishes an answer that should serve to 

 keep the subject still in the field for discussion, B. cholerae snis has 

 a great deal to do with hog cholera and serum j^roduction but icJiat 

 and how important its connection is we cannot say. 



Dammann and Stedefeder* have recently published the results of a 

 series of researches carried on at the veterinary college at Hanover. 

 They produced hog cholera with filtrates of blood and diseased organs 

 of hog cholera pigs. From one outbreak they isolated an or-ganism 

 showing the morphological and most of the cultural and biological 

 characters of B. cholerae suis. This organism they designated B. 

 suipestifer, Voldagsen. They were not able to produce hog cholera by 

 use of filtrates from pigs in this outbreak. Ctiltures of B. suipestifer^ 

 Voldagsen, fed in large doses produced a septicaemia and death in a 

 few days; fed in small doses it produced a more marked diphtheritic 

 enteritis. The culture injected could be recovered in all cases. Fatal 

 results followed subcutaneous or intravenous injection of their B. 

 suipestifer. They likewise succeeded in producing hog cholera (or a 

 disea.se resembling it) by cohabitation of healthy swine with pigs 

 infected artificially with B. suipestifer, Voldagsen, or with pigs natur- 

 ally infected in the Voldagsen outbreak. 



Their agglutination tests and biological tests indicate that B. suipes- 

 tifer, Uhlenhuth, is closely related to B. paratyphi B, and that B. 

 suipestifer, Voldagsen, is a distinct specific organism having high 

 virulence and producing an epizootic swine disease answering to the 

 descriptions of hog cholera. 



They believe that there is sufficient difference in the pathology of 

 the lesions to permit of distinguishing bacillary hog cholera from that 

 produced by the ultravisible viiiis. 



SUMMARY. 



GENERAL. 



B. cholerae suis is an easily isolated organism in a great many cases 

 of hog cholera. Possibly it is present in all cases. 



A living virus capable of producing hog cholera passes through the 

 Chamberland filters that keep back any form of B. cholerae suis or other 

 organisms capable of multiplying in vitro to the extent of being sus- 

 ceptible of demonstration. 



B. cholerae suis is capable of producing a disease in pigs quite similar 

 to natural hog cholera and to the disease produced by the filterable 

 virus. 



The protection offered by the Dorset-Niles serum against the filter- 

 able virus may also extend to virulent cultures of B. cholerae suis. 

 Whether it is necessary to protect against B. cholerae suis in practice 

 is not determined. 



The relation of B. cholerae suis to the filterable vims or to natural 

 outbreaks of hog cholera is not determined by our work or to our 

 satisfaction bv the reseiirches of others. 



