Tracheal Mite
Causal agent |
Acarapis woodii – mite. The mite is
143-174 mm long in the female and
125-136 mm long in the male. |
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Age group |
Parasitises young bees up
to 2 weeks old |
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Egg |
Larvae |
Pupae |
Adult - worker |
Drone |
Queen |
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No |
No |
No |
Yes |
Yes |
Yes |
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Clinical signs |
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None |
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May contribute to Colony Collapse Disorder |
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Bees may have disjointed wings and be unable to fly. Seen crawling around the entrance |
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Bees die early |
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Honey production reduces |
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Tracheal mites inside a honey bees trachea x100 |
Greasy patty to control Tracheal mite infestation |
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Infectivity |
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Very infective. Most
colonies are infected |
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Transmission |
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Between bees. The first egg hatches is a male
and the subsequent mites are female.
The male mates with his sisters |
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Post-mortem Lesions |
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Mites live in the
prothoracic tracheal system. There may
be 100’s of mites in a single bee. |
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Diagnosis |
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Dissection and examination of the prothoracic tracheal system
especially those found crawling around the entrance. Other Acarapis mites have different
habitats. |
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Healthy uninfected tracheae |
Stained tracheae indicating severe infection |
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Obtain fresh bees and place in 70% ethyl alcohol as soon as
possible awaiting detection. |
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Diagnostic method: |
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Pin the bee on its back. Remove the bee’s head and first pair of legs by pushing them off
with a scalpel or razor blade in the
downward and forward motion. |
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Cut a disk of thin transverse section of the pot |
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Place the disk on a microscope slide and add a few drops of
lactic acid. This makes the material
more transparent and helps to separate the muscles. |
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With the aid of a dissecting microscope carefully separate
muscles and examine trachea. |
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Remove suspect trachea and examine at x40-100. |
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Note the mites are extremely common and may be present without
any clinical signs. |
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Treatment |
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Grease patties placed in the autumn through
winter – they interfere with the ability of the mite to recognised the young
bee |
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Grease patty – Vegetable shortening
plus sugar (1:3 ratio). Add 4.5g
peppermint flavouring. Place handful of
patty place on waxed paper top and bottom and place between the two
boxes. Remove top layer of waxed
paper. |
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Some Russian bees are claimed to be
resistant |
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Reduce drifting and robbing |
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Re-queen annually to keep strong colonies |
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Reduce other stresses |
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Maintain excellent biosecurity |
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Menthol fumes are toxic to the
mites. Fume all equipment. Note requires warmth to make the menthol
crystals fume. |
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Formic acid can be used on the bottom
boards. This can be useful to control
tracheal mite. Administer 30 mls every
week for 3 to 5 applications in the spring.
Then again in June. Air
temperature needs to be above 22C but below 30C |
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Other |
The condition is associated with Acute
and Chronic paralysis virus |
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Common differentials |
There are two other Acarapis spp
affecting Honey bees, A. externus, A.doralis. These are none pathogenic but look
extremely similar. |
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Zoonosis |
None |
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