20 ROYAL SOCIETY OF CANADA 



with tuberculosis presence their nutrition surprisingly well until towards 

 the last when they go clown hill rather rapidly. The injection of the 

 serum,, although given in less than half the quantity employed in the 

 first instance still caused considerable local disturbance, and this was 

 aggravated by the animals scratching themselves so that the loss of 

 weight is no doubt to be attributed to the interference with their feed- 

 ing and the general irritation. 



In comparing the results I found, as was expected, that the guinea- 

 pigs are much more susceptible to tuberculosis than are rabbits, losing 

 weight rapidly from the first and presenting marked lesions when 

 killed. These facts led me to keep the rabbits under observation some 

 three weeks longer, in the hope that thus the resulting disease would be 

 more pronounced. This however did not prove to be the case. 



After a careful consideration of the extent and nature of the 

 lesions produced in the pigs it could not be said that the injection of 

 the goat serum had the slightest efEect in inhibiting the action of the 

 bacilli. The results in the case of the rabbits were rather .more pro- 

 mising. The most marked difference was found in rabbits III. and 

 XII. Number three which had been given serum presented no positive 

 appearance of tuberculosis, while its mate, number twelve, presented 

 caseation at the site of inoculation and tubercles on the peritoneum. 

 On the whole the lesions were slightly more marked in the case of the 

 rabbits not receiving the serum. In corroboration of this finding may 

 be cited the results of the first experiment where the only two animals 

 that developed tuberculosis were those that had not been given serum. 

 It is of course hazardous to draw too positive conclusions from such a 

 small number of animals but it would appear so far as we have gone 

 that normal goat serum does have a slight retarding effect on the pro- 

 gress of tuberculous infection. Whether this action is specific or not is 

 another question. Eecent work has shown that the serum of other ani- 

 mals, such as the dog, the ass, and the horse, as well as normal saline 

 solution possess' similar properties. 



The Effects of Serum of Immunized Goats. 



Having drawn this conclusion it was thought advisable to attempt 

 to confer upon the serum more active antitoxic properties. The method 

 adopted was based on that employed in the production of diphtheria 

 antitoxin, namely the introduction of the toxins of the bacillus into the 

 system of an animal until it was immune to the effects, and then using 

 its serum as a curative agent. As has been pointed out most of the 

 work on these lines has proved to be a failure or at most has had a very 

 limited meed of success. This is possibly due, at least in part, to the 



