50 VACCINE AND SEBUM THEEAPY 



When, to obtain anti-anaphylactic immunity, we 

 employ the method of repeated small doses, we are 

 only provoking a series of slight successive anaphy- 

 lactic shocks ; the great shock is thus broken by the 

 reaction being made slower and being divided into 

 small doses. Anaphylactic shock is also a desensitisa- 

 tion, only, instead of being slow, it is rapid ; therefore, 

 the whole difference in anaphylactic shock and the 

 changes that take place in the formation of anti- 

 anaphylaxis is in the time of reaction. 



Clinically, especially in canine practice, w^hen w^e do 

 not know the previous history of our patient, if we are 

 about to employ serum treatment, we should always 

 have resource primarily to anti-anaphylactic vaccina- 

 tion. For all we know, the patient may have had a 

 previous dose of serum, and is, therefore, in the 

 sensitised condition. Only a very short time ago this 

 fact was brought very forcibly to my notice. In a fox- 

 hound kennel I have seen three puppies die and four 

 become violently ill from the use of antidistemper 

 serum. The first dose of serum sensitised these 

 puppies, and the second dose caused the anaphylactic 

 shock. These puppies were attacked with anaphy- 

 lactic symptoms within ten minutes of receipt of 

 second injection. 



The symptoms of anaphylaxis I have described are 

 seen chiefly in dogs and other small animals. The 

 symptoms in cattle and horses are swelling and 

 oedema of the head, especially around the muzzle, 

 excitement, colic, and bloody diarrhoea; in severe 



