242 DISEASES OF POULTRY. 



wise the blood, which is very virulent, may remain 

 on the surface of the ground to cause another out- 

 break of the disease. The birds which die from 

 cholera should in all cases be cremated or deeply 

 buried. 



Vaccination. — Vaccination can not be recom- 

 mended as a preventive. The susceptibility of differ- 

 ent breeds of birds varies to such an extent that a 

 vaccine which is safe for one may be deadly for 

 another. If we had only one breed of birds to deal with 

 there is little doubt but that vaccination would be 

 adapted to it and made a practical preventive; but 

 with so many breeds, each varying from the other, the 

 task of the vaccinator is discouraging. 



An interesting discovery in this connection was 

 made by Dr. Kitt, a German veterinarian. Kitt 

 found that the eggs of fowls that had been made im- 

 mune to cholera contain something analogous to 

 antitoxin, which may be used to produce immunity in 

 other birds. He injects from one to two and one- 

 quarter drams of the white of the eggs under the skin 

 of the bird to be protected. From what we know 

 concerning the antitoxins of other diseases, it is 

 probable that such eggs would be more useful in treat- 

 ing sick birds than in vaccinating well ones against 

 the disease. 



It would not be a difficult matter to vaccinate or 

 inoculate a number of hens until they had a very high 

 degree of immunity, and their eggs should then, ac- 

 cording to this doctrine, be of great remedial value. 

 For valuable birds this treatment might be of service, 

 but it is doubtful if there would ever be sufficient call 

 for the remedy to warrant any one in making the 

 necessary preparations to supply it when needed. 



