674 
ROBERT H. WILSON. 
Tuberculosis Vaccine. Among the various vaccines that have 
devised for animal tuberculosis, perhaps von Behring’s bovovac- 
cine is the best known. It consists of attenuated tuberculosis 
organisms, usually the human variety. The commercial product 
is prepared by using a weakened culture of the organism, which 
is grown on suitable media, carefully dried at a temperature which 
will not destroy its activity and finely pulverized. It is then 
accurately weighed out into 1 containers and sealed. The practical 
value of this product is rather doubtful. 
Bacterins. (Bacterial Vaccines.) Bacterial vaccines are bio¬ 
logical products of comparatively recent origin. They consist of 
dead pathogenic bacteria suspended in normal salt solution, stand¬ 
ardized by determining the number of bacteria per centimeter of 
suspension, and are administered hypodermatically. Their thera¬ 
peutic effects depends upon the fact that they increase the opsonins 
in the blood. When a bacterial vaccine is injected into the tissues 
of a patient suffering from an infection of the corresponding live 
organism, the formation of the special opsonin having the power 
of reparing that bacterial species for phagocytosis is stimulated. 
In veterinary medicine bacterial vaccines are used chiefly for the 
treatment of suppurative conditions. The vaccine may be monov¬ 
alent, that is contain but one strain of bacteria, or polyvalent, 
containing two or more strains. They may be prepared from 
cultures obtained directly from the disease processes of the pa¬ 
tient, in which case the vaccine is called a personal or autogenic 
vaccine, or similar organisms obtained elsewhere may be used 
These latter are known as stock vaccines. 
Bacterial vaccines are indicated in strangles, influenza, puer¬ 
peral fever, erysipelas, fistula, quittor, abscesses; in fact all in¬ 
fectious diseases or conditions due in main or in part to any of 
the staphylococcus or streptococcus organisms. They may be 
used advantageously in pneumonia and colon infection. 
As cases vary in character and extent, no hard and fast rule 
of dosage can be laid down. The clinical symptoms should be 
the guide as to the size of doses administered. 150,000,000 
organisms may be considered an average initial dose, the dose 
