The gazette-times. [volume] (Heppner, Or.) 1912-1925, 1914-08-27
Bee Infection Cured by Heat
By L. F. White, M. D., Ph. D.

made indicated that the germ is easily
killed by heat. This belief has been
confirmed by further experiments.
American foul brood is the disease
of the brood of bees that is best known
to beekeepers and is the one the pres
ence of which they have been able to
recognize most easily. In this disease
the larvae usually die after the cells
containing them are capped. The dis
ease is characterized especially by the
marked viscidity (ropiness) manifest
ed by the decaying larvae that are
dead of the disease. The pronounced
odor noticeable within hives housing
colonies affected by this disease, espe-
cially in its later stages, is another
we'll known characteristic.
Until seven years ago the cause of
American foul brood was not known.
At that time the fact was demon
strated positively that the germ caus-
ing the disease is the one to which the
name bacillus larvae is given.
The facts obtained to date are too
meager to Justify anything more than
a general statement regarding the
minimum amount of heating that can
be employed in rendering material con-
tanning the germ of American foul
brood non-nfeetious. Taking rather
wide limits, it may safely be said that
the minimum temperature at which
| this can be done, if the temperature IS
applied for 10 minutes, lies somewhere
between 90 degrees G. (194 degrees r.
and 100 degrees G, (2l2 degrees F).
1t seems quite probable, indeed, that
a temperature less than 9s degrees G..
| (20S.4 degrees F.) will suffice if ap
plied for 10 minutes. When 100 de
grees C. was used the spores of baccil-
lus larvae were killed in less than five
minutes.
Sacbrood.
Observant beekeepers have for many
/ wears noted the presence of dead brood
which seemed to them to be different
from that dead of foul brood. Some
were inclined to believe that the dis
1 ease was an infectious one; a larger
number apparently were disposed to
ascribe the trouble to such causes as
an unsatisfactory queen, starvation,
and the like. This brood disease has
been recently demonstrated to be an
infectious one, and the name "sac,
brood has been given to it. Larvae
that die of this disease do so almost in
variably after the time of cell cap
ping. The most characteristic symp-
, tom of the disease is the saclike ap-
pearance of the dead larvae when they
, are removed from the cell This fact
suggested the name sacbrood' y for
, the disease.
More than a year ago it was again
, the writer's fortune to determine the
cause of another brood disease I'm
| like the cause Of either European foul
brood or American foul brood, the in
) fecting agent causing sacbrood has not
{ vet been seen. 1t was demonstrated
= however, that the injecting agent in
2 this disease passes through the pores
? of earthenware filters. For this reason
Il the cause of sacbrood is spoken of as
t filterabe virus.
t In paper announcing the cause OF
9 sacbrood the statement is made that
$ the germ causing the disease is de
s stroyed by comparatively small
v amount of heat This belief is con
| frmed by the results of experiments.
: Very little is known about the dis
j eases of adult bees Many names have
: been used for the purpose of desig
mating chem, but tho number of sucl
diseases is probably small. There il
only one adult disease that can b'
!. diagnosed at present by laboratory
n methods. This one is the Nosema dis
!. ease.
Nosema Disease.
Fifty.seven years ago DR.. D0nhot
q made a more or less brief study of
a disease of adult bees in Germany. Fl
s observed that the stomach was th
:, organ that was primarily affected. B,
y feeding to healthy colonies in sirup tn
n crushed stomachs from affected bee
e Donhoff demonstrated that the diseas
n could be transmitted to healthy colo
,e MES. It was therefore infectious.