QUESTIONS 209 



fast. In old abscesses the bacilli present involution forms and stain 

 poorly. 



Cultural and Biologic Properties. The Bacillus pyogenes suis grows 

 best on coagulated blood serum at blood temperature in the incubator. 

 It also grows on agar, in gelatin stick cultures, and in bouillon. The 

 latter remains clear, or becomes very slightly cloudy. A whitish 

 sediment collects at the bottom of the tube. On blood serum whitish, 

 delicate, dry, punctate colonies, which liquefy the culture soil slightly, 

 develop after several days. On potatoes a similar growth occurs. 

 No gas is formed in glucose agar. 



Experimental Inoculation. The Bacillus pyogenes suis is pathogenic 

 to rabbits and mice when injected into the peritoneal cavity. It pro- 

 duces a purulent peritonitis, with a tendency to encapsulated abscess 

 formation, resembling that occurring in the hog. In hogs the natural 

 mode of infection is by inhalation or through wounds, such as 

 castration wounds, injuries in the mouth, umbilical cord, etc. 



QUESTIONS. 



1. What organism is most commonly the cause of suppuration in horses? 



2. What other organism causing suppuration in man causes a similar process 

 in the horse? 



3. What organism causes strangles in the horse? Under what other names 

 is this infection known? 



4. Where is the Streptococcus equi found in strangles and what other equine 

 diseases does it sometimes cause? 



5. Describe the morphology of the Streptococcus equi. 



6. What are its staining properties? 



7. Describe a bouillon culture of the Streptococcus equi. 



8. Also a growth on agar, gelatin, and blood serum. 



9. What animals are susceptible to infection with the Streptococcus equi? 



10. What bacteria have been found in the blood of horses dead from Morbus 

 maculosus? 



11. Describe the organism found bySchiitz in contagious pleuropneumonia of 

 horses. 



12. Describe the organisms found as the cause of apoplectiform septicemia in 

 chickens. 



13. What kind of disease is botryomycosis? What is its etiologic factor? 



14. Why is botryomycosis in some of its features like tumor formation? 



15. Describe the seat and appearance of botryomycotic lesions. 



16. Describe the Botryococcus ascoformans as seen in pus both with the naked 

 eye and with the microscope. 



17. What is a zoogleal mass? how is its formation brought about? How does 

 it look in a pure culture of Botryococcus ascoformans? 



18. How does the organism look in pure culture on agar? 



19. For what animals is the organism pathogenic? 



20. Under what conditions does the Staphylococcus pyogenes aureus produce 

 botryomycosis ? 



21. Name the bacteria which are generally the causes of suppuration in cattle. 



22. What is generally the cause of pyelonephritis in cattle? Describe the 

 organism and the pathogenic changes which it produces. 



23. What are the cultural properties of this organism? 



24. What is a hematogenous infection? 



25. What organism generally produces suppuration in hogs? Describe its 

 morphology. 



26. Describe the abscesses due to this organism. 



27. Describe the cultural properties of the Bacillus pyogenes suis. 



28. What animals are susceptible to it? 



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