474 Chapter XV 



were cultivated in broth and sent out in tubes similar to those em- 

 ployed in the distribution of the anthrax vaccines. 



The vaccines are in themselves innocuous and are capable of 

 communicating to the inoculated pig an immunity sufficiently durable 

 to be of real service. Young pigs being less susceptible to the 

 erysipelas than are the adults, it is generally preferred to vaccinate 

 young pigs of from two to four months. The vaccination is done at 

 two separate times. The first vaccine, in a dose of one-eighth of a cubic 

 centimetre, is inoculated subcutaneously on the inner aspect of the 

 right thigh ; the second vaccine is inoculated in the same way, 12 or 

 15 days later, into the left thigh. The immunity that follows these 

 vaccinations is not fully established until the end of the second week. 



In spite of the many advantages of the Pasteurian method the 

 vaccinations against swine erysipelas have not spread so much as 

 one might have expected ; and they have found a general applica- 

 tion abroad rather than in France. It is only necessary to cast a 

 glance at the statistics to be convinced of this. From the date of 

 the introduction of the Pasteurian vaccinations in 1884 up to the 

 1st January, 1900, there had been vaccinated in France in all 428,746 

 pigs, whilst abroad, where the vaccinations were introduced some 

 [497] years later, the number of pigs vaccinated was 4,819,387- Of this 

 number the great majority (4,194,191) had been treated in Hungary. 

 The losses amongst the vaccinated animals were insignificant (1'68 %) 

 when compared with an average mortality of 20/o amongst un- 

 vaccinated pigs. 



This limited extension of the vaccination of pigs in France arises 

 from various causes. In many countries the breeding is on too small 

 a scale to allow of the intervention of the veterinarian and of the 

 expenses which the vaccinations involve. On the other hand, it 

 cannot be denied that the Pasteurian method presents certain draw- 

 backs in practice. The living, although attenuated, bacilli introduced 

 may sometimes serve as centres of infection, especially in cases, rare 

 no doubt, where the vaccinated animal contracts a chronic form of the 

 disease. The Pasteurian vaccines must, therefore, be avoided in dis- 

 tricts where the erysipelas has not yet appeared. Their application 

 in countries already infected presents the further drawback that the 

 immunity requires for its establishment a fairly long time, sufficiently 

 long to permit the micro-organism to kill a large number of pigs 

 before the vaccines have conferred any immunity upon them. 



It is natural that, under such conditions, an attempt has been 



