46 Veteri?iary Medicine. 



was given to each animal. Of 1923 cases treated (1897-8) 30 per 

 cent, died, and 70 per cent, recovered. Of 3197 in abandoned 

 herds (checks), 81.24 per cent, were lost. (De Schweinitz.) 



One drawback was found in the short period of immunity 

 secured, the susceptibility reappearing as soon as the antitoxin 

 had been eliminated from the body. This was met in part by 

 using sterilized cultures (toxins) along with the serum. 



Another desideratum was a speedy means of distinguishing in 

 field work between hog cholera and swine plague, as the antitoxin 

 of the one was not protective against the other. To meet this, 

 serum was obtained from an animal immunized to both diseases, 

 or a mixture was made of the sera of two animals respectively 

 made resistant to the two affections. 



De Schweinitz was very optimistic in the matter, claiming that 

 the serum is absolutely harmless, can be used on pigs freely, and 

 will cost but 15 cents for each animal. He estimated that of the 

 $15,000,000 per annum lost by Hog Cholera and Swine Plague in 

 Iowa alone, $1 1,000,000 can be saved at a comparatively small 

 cost. 



The method is scientifically sound in availing of the defensive 

 products of the immunized system for imparting to the animal 

 attacked, the power of vital resistance, and after allowing for en- 

 thusiasm, for the inevitable mistakes, when used on a large scale, 

 of other deadly swine diseases for hog cholera, for the many acci- 

 dents incident to its application by operators who are not specially 

 trained like the employes of the Bureau, for its demand for acute 

 and deadly outbreaks, as well as for chronic and mild ones, and 

 taking into account that in other hands it has not fully borne out 

 the promise made for it ; yet it seems to have some measure of 

 merit, and where no systematic attempt is made by the authorities 

 for the extinction of the disease and its germ, it is an available 

 resort for the owner of herds. 



The fundamental objection is that it entails the preservation, 

 encrease and spread of the poison, and like all temporizing meas- 

 ures, stands as a barrier to the complete extinction of the plague. 

 Giving such a very transient protection, its repetition may be de- 

 manded in a few months or a year, and proceeding on the ground 

 that the pest must continue for all time, the apparent economy of 

 the process will prove, in the long run, but a permanent and 

 grievous tax. 



