Blackleg 865 
large part of this country, and causes serious losses in 
the central and western stock-raising states. 
Calves that are in good condition, or fat, are more 
likely to contract the disease than those in thin flesh. 
In some countries, the disease is said to be confined to 
low-lying pastures; but in the western states it is quite 
as frequent on the high, dry prairies as on lower lands. 
It is thought that the germ of the disease does not 
belong naturally within the animal body; but, taken 
into the bodies of young cattle, it finds conditions favor- 
able for multiplying, and produces the disease. Black- 
lez may develop on pastures and ‘in localities where it 
has never been known before, and where there seems 
to be no possibility of the germs having been in- 
troduced. 
The affected calf is first noticed lying down apart 
from the others. If driven up, it is found to be stiff and 
lame in one leg, or one whole side of the body may 
be almost useless. There are swellings on some part of 
the affected leg or side, which, if rubbed firmly with the 
hand, will be found to be filled with gas and will emit a 
crackling sound. This is a characteristic symptom of 
this disease. Calves with blackleg will usually live 
for some days; only a few recover. 
Well calves should be removed to uninfected pastures 
or quarters, and given water that has not been contami- 
nated. Medicinal treatment is of little value. Exer- 
cise and purging with salts are recommended, the latter 
being given as a drench in one-half to one pound 
doses. All susceptible animals should be vaccinated 
with blackleg virus—a safe and reliable preventive. In 
