This is to my mind a good example of info scientists can give
beekeepers.

R

========

Here is most of what we know about AFB and foundation

Mark Goodwin <[log in to unmask]>


TITLE:  Investigations on the sterilization of beewax for foundation
production.
AUTHOR(S):  Kostecki-R; Jelinski-M
SOURCE (BIBLIOGRAPHIC CITATION):
Bulletin-of-the-Veterinary-Institute-in-Pulawy. 1977, 21: 1-2, 6-9; B.
LANGUAGE OF TEXT:  English
ABSTRACT:  Carbon tetrachloride was used to wash Bacillus larvae spores
from combs taken from colonies with AFB; it was possible to grow the
spores in artificial media. In tests in which suspensions of B. larvae
spores were added to the food of larvae 3-5 days old, 26% of larvae were
killed when given 2 X 10^7 spores in 1 ml of feed. Wax samples, wax
strips and foundation taken from several Polish state wax-processing
units were examined for the presence of spores; in 426 tests, single
endospores were found in 4 samples (all wax).  Wax used for producing
foundation is heated to 95-100 deg C for about 1 h, which probably kills
most strains of B. larvae, if present; it is suggested that wax from
infected apiaries should either be extracted with carbon tetrachloride
or sterilized in an autoclave at 121 deg C for 30 min.
 P. Walker
PUBLICATION TYPE:  Journal-article
ACCESSION NUMBER:  780207345

TITLE:  The sensitiveness of the foulbrood bacterium Bacillus larvae to
heat treatment.
AUTHOR(S):  Hansen-H; Rasmussen-B; Ritter-W (ed.)
SOURCE (BIBLIOGRAPHIC CITATION):  Proceedings of the International
Symposium on Recent Research on Bee Pathology, September 5-7, 1990,
Ghent, Belgium.  1991, 146-148; Bd.
PUBLISHER INFORMATION:  Rijksstation voor Nematologie en Entomologie on
behalf of Apimondia; Merelbeke; Belgium
LANGUAGE OF TEXT:  English
ABSTRACT:  A Yugoslav sunflower honey with 2.2 X 10^5 B. larvae spores/g
and a Danish rape honey with 7.5 X 10^6 B. larvae spores/g were heated to
100°C.  At this temperature samples were taken at different times between
10 and 40 min.  The samples were inoculated into J-agar dishes which were
incubated at 35°.  Growth of B. larvae was proved in the Yugoslav honey
after heating for 15 min, but not after 20 min.  In the Danish honey
growth was proved after 27.5 min but not after 30 min.  Wax from combs
taken from 6 colonies with clinical symptoms of AFB was heated to 90°.
At this temperature samples were taken after 10, 15, 20, 30 and 32 min.
In all samples, growth of B. larvae was found when the wax was
inoculated into J-agar dishes.  Six batches of wax treated in a wax
processing factory were examined.  The wax came from colonies with 1.8 X
10^4 - 4.6 X 10^6 B. larvae spores/g honey.  The wax was melted with steam
at about 119°. After melting, the wax was kept in a container for 15-30
min at about 80°.  In one of the batches a very light B. larvae infection
was proved.  In the remaining batches, B. larvae could not be found.
Samples of comb foundation from 10 batches of unknown origin and from 2
batches originating from colonies with AFB were also examined. The wax
had been treated in a wax processing factory.  B. larvae was not found in
any of the batches.  It is concluded that the procedure in the wax
processing factory is generally sufficient to prevent the spread of B.
larvae.  When material from hives treated with a gas flame was inoculated
into J-agar dishes growth of B. larvae colonies occurred.
PUBLICATION TYPE:  Miscellaneous
ACCESSION NUMBER:  920232175

TITLE:  Resistance of Bacillus larvae in beeswax.
AUTHOR(S):  Machova-M
SOURCE (BIBLIOGRAPHIC CITATION):  Apidologie. 1993, 24: 1, 25-31; Bj.
LANGUAGE OF TEXT:  English
LANGUAGE OF SUMMARIES:  French, German
ABSTRACT:  The heat resistance of Bacillus larvae spores introduced
artificially into beeswax was studied by exposing the wax to a
temperature of 150°C and testing the viability of the spores at
intervals.  The number of viable spores in the wax decreased with time;
initial concentrations in 2 samples of wax of 3X10^5 and 3X10^8 viable
spores/g wax decreased to 0 after 20 and 60 min, respectively (although
such heating would cause physical and chemical changes in beeswax).
Spores maintained their viability when incubated in nutritive broth with
0.5% sulphuric acid for 37.5 h, the time required for the isolation of
the spores from the wax.
PUBLICATION TYPE:  Journal-article
ACCESSION NUMBER:  940200098

TITLE:  Experiences with the beeswax disinfection by overheating.
AUTHOR(S):  Machova-M; Skrla-M; Bacilek-J; Vesely-V; Peroutka-M
SOURCE (BIBLIOGRAPHIC CITATION):  Apiacta. 1992, 27: 3, 65-71; Bj.
LANGUAGE OF TEXT:  English
ABSTRACT:  Heat treatment of wax containing spores of Bacillus larvae
may not kill all the spores unless the exposure temperature is
sufficiently high.  To determine the effect of high temperatures on the
wax itself, small (1 g) samples were gradually heated to 150°C and then
cooled.  The resulting wax was darker, and its chemical composition had
changed somewhat.  However, it was accepted by honey bee colonies.
Changes in composition were also found after exposure to 110° or 120°;
samples exposed to 150° for a short time were less affected than those
exposed to 120° for a longer period. The changes in colour and
composition could not be reversed by heating with water and phosphoric
acid.  In a test on an industrial scale, 400 kg wax, contaminated with
2.1 X 10^8 spores/g, were heated to 118° over 3 h 15 min, kept at the
temperature for about 10 min, then allowed to cool.  No chemical changes
occurred, and all spores were killed.
PUBLICATION TYPE:  Journal-article
ACCESSION NUMBER:  930233842