QUESTIONS 261 



The animal becomes restless and dies within two to four days, a 

 hemorrhagic discharge from the mouth arid nostrils appearing shortly 

 before death. The postmortem examination shows a hemorrhagic 

 oedema of the subcutaneous tissue and heniorrhagic serous exudates 

 in the body cavities. The two authors named have succeeded in 

 obtaining germ-free solutions, of which two milligrams or even one- 

 half milligram would kill a guinea-pig of one-half pound weight 

 (250 grams). The toxin which has these pathogenic properties is 

 not very stable; it is destroyed in one hour if heated to 50 C., 1 per 

 cent, carbolic acid solution destroys it in twenty-four hours, but 

 chloroform has no deleterious effect upon it, and is used as a means 

 for its conservation. The authors also succeeded in preparing an 

 antitoxin. Guinea-pigs could not be actively immunized against the 

 toxin, on the contrary, a repeated injection of small doses produced 

 a hypersusceptibility. Rabbits, however, can be actively immunized, 

 and also cattle. The blood serum of cattle after a systematic course 

 of hyperimmunization lasting four to five months often develops a 

 high antitoxic or immunizing value, and the antitoxin has the great 

 advantage of being apparently quite stable when properly kept and 

 stored. It was found to be thermostabile, and heating it for three 

 hours at 60 C. had no detrimental effect upon it. The "Rauschbrand" 

 antitoxin of Grassberger and Schattenfroh, however, is valueless in 

 the treatment of natural or artificial infection with the black-leg 

 bacillus, because death is not caused by the soluble toxin but by 

 factors which are in no way affected by the antitoxin. The latter, 

 particularly on account of its very peculiar behavior toward its toxin, 

 is, therefore, of theoretical interest only. 



QUESTIONS. 



1. What are the other names of the disease black-leg? 



2. What is the cause of this disease of cattle? 



3. At what age are cattle most susceptible to the disease? 



4. Describe the most characteristic pathologic lesions of symptomatic anthrax. 



5. What is the meaning of the terms emphysematous, crepitant, tympanitic? 



6. What is a collateral anemia? Explain its occurrence in black-leg. 



7. Describe the morphology and staining properties of the Bacillus sarco- 

 physematos bovis. 



8. What is a clostridium? 



9. Describe the cultural properties of the bacillus of black-leg. 



10. What substance added to the ordinary culture media greatly favors the 

 development of the organism? 



11. Describe Kitt's method of cultivating the bacillus from the juice of infected 

 meat or from a small piece of the latter. 



12. Describe the differences in the action of the anthrax bacillus and the 

 Bacillus sarcophysematos bovis in the blood of animals dying from these two 

 diseases, respectively. 



13. What animal may be used to differentiate by inoculation experiments 

 between the black-leg bacillus and that of malignant edema? 



14. What is the natural mode of infection of symptomatic anthrax in cattle? 



15. Discuss the resistance of the spores of the bacillus. 



16. Which spores are and which are not destroyed by phagocytosis? How 

 can the phagocytosis of toxin free spores be prevented? 



