158 
FOWL CHOLERA. 
be accepted from a place known to be infected for at least a year 
after the last known cases occur. 
2. Precautions in regard to eggs. —All eggs from a distance to 
be used for hatching must be thoroughly cleaned of all particles 
of excrement adhering to them, and the water with which they are 
washed, as well as cloths or brushes used, must be raised to the 
boiling point before being thrown upon grounds to which poultry 
has access. The virus is always destroyed by a boiling tempera¬ 
ture, or even by 140° F., if maintained for fifteen minutes. 
3. Fowls not to wander upon adjoining infected premises. —A 
stone wall is, in towns, frequently the boundary line of an infected 
place, and though fowls are upon each side of it the contagion 
may not cross for years. In such cases it is a matter of the great¬ 
est importance to prevent the healthy fowls from trespassing upon 
the infected grounds. 
4. Fowls from neighboring inf ected premises to be rigidly ex¬ 
cluded. —If it is important to keep healthy fowls from infected 
grounds, it is not less important to exclude fowls living in infected 
quarters from entering on runs that are still free from the disease. 
Even though insusceptible to cholera and, consequently, healthy, 
they are able to carry the virus on their feathers and feet and 
may even distribute it with their own excrement; for although 
the virus is unable to propagate itself in the blood and tissues of 
insusceptible birds, there is reason to believe that it may still 
multiply in the contents of their digestive organs. 
5. Other infected substances to be excluded from the runs .— 
Manure from infected places is often purchased and spread upon 
land to which healthy poultry has access, and thus becomes a 
means of spreading the disease. This should either be entirely 
excluded from the farm or the fowls should not be allowed to 
come near where it is placed. It cannot be safely disinfected. 
Feathers and dead birds are also at times carried a considerable 
distance by various agencies, and should be guarded against when 
possible. 
By a careful observance of these rules the fowl cholera may 
be excluded indefinitely, and may be exterminated when it has 
made its appearance. The writer has had a very virulent form 
