76 VACCINE AND SEBUM THERAPY 



1. Two inoculations with attenuated virus (method 

 of Arloing, Cornevin, and Thomas). A vaccine is 

 prepared from diseased powdered muscle by attenuat- 

 ing the virus through heating to a high degree of 

 temperature. For this purpose the diseased part of 

 the muscle is ground in a mortar with some water, 

 and dried in a thin layer at 37° C. ; then the dry mass 

 is mixed with two parts of water, and one half heated 

 at 100° to 104° C, the other at 90° to 94° C. for seven 

 hours. The former makes the first weaker vaccine, 

 the latter the second stronger one. 



The dried material is either compressed in one-dose 

 tablets or pellets, or threads are soaked in a suspen- 

 sion of the attenuated organisms. The threads are 

 collected into small bundles, each bundle constituting 

 a dose. The pellets are injected under the skin by 

 means of a hollow needle fitted with a plunger ; the 

 thread form is introduced into the skin of the tail by 

 means of a special needle provided with a notch to 

 hold the threads while being inserted. The second 

 inoculation is made ten to twelve days after the first 

 one. The immunity reaches the necessary degree in 

 eight to ten days after the second vaccination. Until 

 then, however, the animals have a lower resistance 

 against the natural infection (negative phase). 



2. One inoculation with attenuated virus. Accord- 

 ing to Kitt, a powder prepared from diseased muscles, 

 after having been heated for six hours in dry air at 

 85° to 90° C, or, better still, in live steam at 97° C, 

 gives a suitable vaccine. One injection of such 



