248 GENERAL THERAPEUTICS FOR VETERINARIANS 



solution is prepared from powdered muscle which has been attenuated by 

 exposure to live steam at 97° C. (or by heating for six hours at 85 to 90° C.)- 

 More recently, pieces of muscle of different origin are used in preparing the 

 vaccine (polyvalent vaccine). 



3. The Blacklegine op Thomas. — Silk or cotton threads containing 

 black leg spores are inserted subcutaneously (back of the shoulder in calves) 

 and permitted to remain. The method is recommended as very simple and 

 effective and has given satisfactory results in Germany (North Dithmarsch). 



Swine Erysipelas. — 1. The Lorenz Method of vaccination and the 

 analogous Susserin consists in the simultaneous injection of immune serum 

 (passive immunization) and bouillon cultures of swine erysipelas bacilli (active 

 immunization). The inoculation is made at the base of the ear, where 

 5 c.c. of serum and 0.5 c.c. of the culture are injected eubcutaneously at 

 the same time (simultaneous vaccination). The immunity established by 

 the vaccination continues about half a year. Simultaneous vaccination has 

 proven very trustworthy in Germany as a protective and curative remedy. 

 Recently, instead of the double inoculation only the serum is injected in many 

 instances. 



2. The Pasteur Method comprises two injections of attenuated cultures 

 of swine erysipelas bacilli (premier and deuxi^me vaccine) on the inner sur- 

 face of the thigh at intervals of 10 to 12 days; the first the weaker and then 

 the stronger vaccine (attenuated by passing through rabbits). This method 

 established a high and long-continuing immunity, but is not without danger 

 (extension of the disease, sometimes great losses). 



Hog Cholera. — By the use of 10 to 20 c.c. of immune serum, obtained 

 from swine highly immunized artificially, a passive immunity is established 

 which begins during the period of incubation and lasts several weeks. The 

 immune serum also has a curative effect on diseased animals. By the simul- 

 taneous injection of immune serum (20 c.c.) and virulent blood (1 to 2 c.c.) 

 an active immunity is produced which lasts for months; this method, however, 

 appears to be not without danger, because a part of the vaccinated swine 

 become affected with hog cholera and eliminate the virus of the disease. 



[In the United States, 20 c.c. of serum are injected for each 50 pounds of 

 body weight both in the serum alone and in the simultaneous method of 

 vaccination.] 



Swine Plague. — ^The several vaccines recommended for swine plague 

 (Septizidin, Suptol, Euman, bivalent and polyvalent serum) have not proven 

 reliable in practice. 



Calf Pneumonia. — The views concerning the value of the different immune 

 eera (Septizidin, polyvalent serum) are divided and contradictory. 



Calf Cholera. — ^The serum vaccination of new-bom calves with polyv- 



