784 EXPERIMENT STATION RECORD. [Vol. 40 



B. paratyphosus ' B,' in conjunction with H. pyocyaneus and B. roli communis. 

 cause enteritis in swine. So-railed 'necrotic enteritis' is not caused b\ B. 

 necrophorus, because it Is seldom found and if present Is considered only as a 

 secondary Invader with little pathological significance. Ho; r cholera is nearly 

 always accompanied by secondary bacterial infections, which have a tendency 

 to Increase the death rate by producing pneumonia and enteritis. 



"Proescher has Isolated, stained, ami rendered visible a micrococcus obtained 

 from the blood of pigs Infected with acute 1 1< »lt cholera ; has obtained this micro- 

 organism in pure culture and transferred same to the forty-second subculture. 

 Inoculation of susceptible pips with the sixth subculture of this micro-organ l<?m 

 has produced hog cholera. This inicroccocus has repeatedly been recovered 

 in pure culture following filtration and subsequently inoculated into susceptible 

 pigs, producing hog cholera with typical lesions, and recovered again in pure 

 culture. The evidence at hand at the present time Indicates that this micrococ- 

 cus causes hog cholera." 



[Hog cholera studiesl (Minnesota Sta. Rpt. 1918, pp. 7?. 74). The prog 

 report for l'.UT 18 includes notes on the following topics: 



I. To determine the possibility <>f producing an active immunity following a 

 passive immunity. — The results obtained are thought to Indicate that an 

 active Immunity can be produced in a passively immunized pig at least 15 days 

 after being injected with serum. 



II. To determine the effect ©/ freezing em antihog cholera serum, a report 

 of this has been previously noted (E. s. l;.. :'.s, p, 187). 



III. To attempt the isolation ami cultivation of tin etiological organism of 

 boa ilmlt hi. Smears made from the blood of cholera infected plgg did not 

 reveal the diplococci, which, according to Proescher, are the etiological factor 

 of hog cholera. 



A study of the endocardial lesions developing during pneumococcus infec- 

 tion in horses, a. I'.. Wadswobth (Jour. Med. Research, 89 [1919), No. .1. pp. 

 ..'7. 1 ' 892, pis. 6). The author discusses the development of the lesions of vege- 

 tative endocarditis during the process <'{ immunizing horses for the production 

 of therapeutic antipneumocOCCUS serum. A study of the lesions in six horses 

 dying through pneumococcus Immunization Is reported which indicates that 

 practically all of the lesions were attributable to the action of the bacteria 

 and their poisons, carried through the circulation of the ti-sues affected. The 

 heart lesions corresponded to those of acute and chronic endocarditis in man. 

 The importance of predisposing injury in determining the localization of the 

 bacteria is demonstrated, but it is pointed out that the bacterial poisons pro- 

 duce this injury, so thai the bacterial localization may he practically coincident 

 with it or may follow it immediately. 



"In order to clarify our conceptions of pneumococcus infection, and doubtless 

 .also streptococcus infection, it is necessary to recognise the parasitic and the 



toxic activities of the inciting BgentS BS distinct phases of the infection- proc- 

 esses, ami yel not as entirely separate or independent activities because they are 

 in point of fact closely linked ami largely if not wholly dependent one upon 

 the other." 



A trypanosomiasis of the horse in Morocco. — A clinical and experimental 

 study. Yr.i.r < /,'< v. den. )i,d. \,t.. j? [1918), \". 822, pp. $89 51 8). —Trypano- 

 somiasis in the horse in Morocco is a very grave disease which fortunately is 

 localized in certain small zones. Control work consists in the complete with- 

 drawal by the cavalry from posis situated within such contaminated areas 

 and the treatment or slaughter of the affected animals. 



