Sacbrood Virus
Causal agent |
Morator aetatulas |
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Age group |
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Egg |
Larvae |
Pupae |
Adult - worker |
Drone |
Queen |
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No |
No |
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Clinical signs |
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Outside |
None |
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Odour |
None |
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Brood |
Few abnormal cells |
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Cappings |
Almost no torn
cappings. Scattered cells. |
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Larvae appearance |
Larvae dies just
before pupation – upright in cell – so normally in capped cell |
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Head development
retarded and head darker than the rest of the body |
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Larvae colour is
pearly white to gray and finally black. |
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When larvae removed
from the cell, often appear to be in a sac filled with water |
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Scales (larvae) |
Grey, brown and
brittle, loose in cell, slipper shaped |
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Sacbrood larvae removed from cell |
“Chinese slipper” |
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Other |
Often seen in
association with Chalkbrood - Ascosphaera
apis |
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Infectivity |
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Virus mildly pathogen
and not resistant |
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Transmission |
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Post-mortem
Lesions |
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Retarded head
development |
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Diagnosis |
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Appearance of larvae |
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Treatment |
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Spontaneous recovery – especially when nectar flows are strong |
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Note concentration of hives in an area |
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Re-queen hive |
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Regular and routine brood comb changes – 3 frames per year per super |
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Common differentials |
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Zoonosis |
None |
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