SERO1.OGY MANUFACTURE AND USE OF SERA AND VACCINES 261 



B. Antibacterial Sera or Bactericidal Sera. 



Antistreptococcic serum. 

 Canine distemper serum. 

 White scour serum. 



C. Bacterins. 



Anthrax. 



Mallein. 



Tuberculin. 



Blackleg. 



Blacklegine. 



Blacklegules (pill form). * 



Blacklegoids (pill form). < 



Hog cholera. 



Fowl cholera. 



White scour. 



Texas fever. 



The above substances resemble each other in that they are organic and 

 of complex chemical composition. They gradually deteriorate and finally 

 become worthless, some sooner than others. Even the comparatively per- 

 manent kinds will not retain their full activities more than a few months, 

 though they may still be sufficiently active therapeutically after eighteen 

 months, or even longer. They should be kept in a cool dry place, away 

 from light. Turbidity in those preparations, which are clear when freshly 

 prepared, indicates that decomposition changes have set in and that they 

 are unfit for use. Many of the bacterins are normally turbid and nearly 

 all of them have some slight color and odor. 



Thus far only a few of the substances above tabulated have proven 

 entirely satisfactory in the treatment of the particular disease or diseases 

 for which they are intended. This is but to be expected since their use is 

 very largely based upon theory. Theory and practice have ever failed to 

 develop along exactly parallel lines. Science is however fortunate in 

 being able to assert that in the antidiphtheric serum we have practically a 

 specific for the cure of diphtheria, provided it is used in time and given in 

 sufficiently large and sufficiently frequent doses. The antitetanic serum 

 has given excellent results particularly as a preventive, as has also the anti- 

 streptococcic serum. Of the bacterins the Staphylococcus has given ex- 

 cellent results in the cure of actual pathologic conditions. Some of the 

 others have proven less satisfactory and in many cases their great useful- 

 ness lies in their preventive rather than curative powers. 



We will explain very briefly the manufacture of a few of these sub- 

 stances only, as the methods are quite closely similar for like agents. The 



