164 CLINICAL BACTERIOLOGY AND 



types. Eight of the controls died, while all of the im- 

 munized dogs remained well.' These dogs were all in the 

 same room and exposed to each other, so there was plenty 

 of opportunity to contract the disease from each other had 

 they been susceptible. 



" From a practical standpoint we have found these pro- 

 tective inoculations of very great value. From the nature 

 of the work carried on in our laboratory, it is necessary to 

 use from fifteen to twenty dogs a week for one purpose or 

 another, and it has always been our experience to lose 

 nearly all of the young ones, not killed at once, to distemper. 

 Since beginning to give some of these dogs protective in- 

 jections as soon as they are received from the dog-pound, 

 our experience is just reversed, and we are able to save a 

 large number of them. 



" This is not only a great help as far as the experiments 

 are concerned, but a great saving from a monetary point of 

 view, and incidentally corroborates our previous results. 

 All of these dogs are exposed to infection before being 

 brought to the laboratory, and many of them have already 

 contracted the disease, so that the fact that we are able to 

 save so many speaks well for the value of the inoculations. 

 We give three injections, with two or three days' intervals, 

 beginning with 200,000,000 bacteria, and increasing the 

 dose by 200,000,000. 



" The dogs have suffered no ill effect whatever from these 

 protective injections." 



Ferry advises as a prophylactic the following doses of 

 devitalized B. bronchocanis, with intervals of from three to 

 five days between. 



First 200,000,000 



Second 400,000,000 



Third 600,000,000 



The vaccine, of course, should be given before symptoms 

 of the disease present themselves. Ferry suggests, for the 

 best results to be obtained, the vaccine should be given a 



