Agriculture Reference
In-Depth Information
inadvertently fed to additional larvae. Thus, the disease spreads within a colony. This
disease will kill a colony, usually within a season.
Because of the seriousness of AFB, most departments of agriculture have regulations
on containment, treatments, and controls. There is only one antibiotic (a tylosin
product) labeled for use when a colony is officially diagnosed with this disease (from
samples taken by a bee inspector and confirmed by a recognized diagnostic lab, such
as the USDA). You cannot use it to prevent the disease, just as you would not take an
antibiotic to prevent a disease you did not have. Resistance to antibiotics is a worldwide
problem and this is one way to prevent that from occurring here. With no medication
to control this disease, and since even good hygienic bees and stress reduction does not
help, what's the answer to AFB? Extreme beekeeper hygiene.
Careful examination and diagnosis can locate symptoms early so that brood frames,
and entire supers if necessary, can be destroyed. Frames with diseased larvae can be
removed and burned, but recall that the larvae don't die until the cells are capped, so
detection isn't easy, especially when the infestation is small and early.
You can assume that in even a mildly infested colony, most of the broodnest-area
bees—those that feed and clean—have AFB spores associated with them. Further, these
are some of the bees that take nectar from foragers, passing spores to them also.
Tip:
Off-color larva are the first red flag a colony raises when something is wrong
European foulbrood-infected larvae are dark brown to black, rubbery and sunken to the
bottom or along the side of the cell. The larvae die before the cell is capped, unlike
American foulbrood-infected larvae, that perish after the cell is capped.
Healthy larvae and pupa, such as those shown here, are pure, glistening white.
