Diseases of Honeybees
Diseases of Honeybees
There
are a number of serious diseases that the honey bee suffers from,
some which affect the brood and others that affect the adult bee.
Of the former AFB (American Foul Brood) and EFB (European Foul
Brood) and Varroa are the main ones. All three diseases are
notifiable and must be reported to MAFF. Of the three only Varroa
can be treated by the beekeeper without permission from the
ministry. Serious cases of AFB must be investigated by a ministry
Bee officer and the colony ,including frames and honey must be
destroyed. The hives can be saved by flaming them with a blow
torch and cleaning throughly. EFB can be treated but must only be
done by a ministry Bee Officer, this is at his discretion if he
co nsiders that it is only a light infection, otherwise he can
order the colony destroyed.
VARROA
is a reddish-brown mite that lays its eggs in the brood cell just
before the cell is sealed over, the mite progeny then hatch out
and feed upon the larvae in the cell, The resulting bees that
hatch are affected in their life expectancy and in some cases
their physical properties. The mites that hatch out feed on the
adult bees and in doing so prompt the growth of viruses, which it
is thought are the main distructive agencies towards the bees.
The
adult bee is also plagued by internal parasites one of which is
NOSEMA, a parasite that lives within the digestive cells lining
the mid-gut of the adult bee, where it passes the active
reproductive phase of its life cycle.Infected worker bees, have
their brood-food glands and their average length of life
shortened , than healthy unaffected bees. The brood rearing and
honey producing capability of the colony is thus reduced to an
extent which depends upon the number of bees infected.
ACARINE.
Acarapis woodi is a small mite that lives in the thoracic trachea
of the honeybee. The fertilized female migrates into the trachea
and lays its eggs soon after the bee emerges from its cell, it
does not do this to older mature bees, seeming to prefer the
young adult bees.These eggs hatch in about five days and the
little larvae d evelop into adult mites in about nine days later.
These mites feed by piercing the walls of the trachae and sucking
the blood of the bee.
CHALK
BROOD. This disease is the result of larvae eating the spores of
the fungus Ascosphaera apis. These germinate in the larvae and
the mould like strands,(mycelium) grow until they have completely
interwoven the body of the larvae. Though fluffy looking ,the
bodies of the larvae are little hard white mummies. Though not a
great problem ,if there are too many, then it is best to requeen
with a queen that is not susceptible to the fungus. Stress is
thought to trigger it off, so treat the hive gently and keep it
clean,
WAX MOTH.
Though not technically a disease the wax moth can be very
troublesome as it moves through the brood combs damaging them and
leaving a trail of old cocoons, silk and dust. They also hollow
out shallow hole for the larvae to pupate in. The main damage is
to stored combs especially brood combs as these have faecal
remains and old cocoon which it seems is a part of the wax moth
caterpiller diet. There are two species of wax moth, the Greater
Wax Moth (Galleria mellomella) and the Lesser Wax Moth (Achroia
grisella).
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