QUESTIONS 219 



sediment is formed. On potatoes either a yellowish-white or a grayish- 

 white growth is formed, but occasionally the organism refuses to 

 develop on this culture soil. The organism is also pathogenic for 

 mice and rabbits. 



QUESTIONS. 



1. What are the characteristic pathologic changes in diphtheritic inflam- 

 mations? 



2. What is the cause of diphtheria in man? 



3. Describe the organism causing the disease. 



4. Describe its staining properties when stained with Loeffler's alkaline 

 methylene blue. Give the formula for this stain. 



5. Give the formula for the preparation of Loeffler's blood-serum mixture. 



6. Describe the growth of the Bacillus diphtherias on this culture medium. 



7. What non-pathogenic bacillus in cultures and stained microscopic speci- 

 mens looks very much like the Bacillus diphtherias? 



8. How does this bacillus act toward oxygen, glucose, gelatin? 



9. What kind of toxins are formed by the diphtheria bacillus? 



10. What domestic animals contract diphtheria spontaneously? 



11. Name a number of animal diseases due to the Bacillus necrophorus. 



12. What other names have been given to the Bacillus necrophorus? 



13. What is the arrangement of this bacillus in infected tissues? 



14. What are the cultural and biologic properties of this organism? 



15. How are pure cultures obtained from pathologic material containing the 

 Bacillus necrophorus and other bacteria? 



16. Describe the pathologic lesions caused by the organism in calves. 



17. Give the description and common cause of multiple liver abscesses in 

 cattle. 



18. What affection of the horse's hoof is frequently caused by the Bacillus 

 necrophorus? What occurs if this hoof disease leads to the death of the animal? 



19. What disease of sheep is caused by the Bacillus necrophorus? 



20. Describe the pathologic lesions as seen in the feet of affected sheep. 



21. What other parts of the body of sheep may become infected with the 

 Bacillus necrophorus? 



22. What animals are spontaneously infected by the Bacillus diphtheriae 

 avium? 



23. Describe the pathologic lesions produced. 



24. Give the morphologic and cultural properties of the Bacillus diphtheriae 

 avium. 



