Chilled Brood is a condition where relatively large areas of brood in all stages die at the same time and turn very dark in colour. Young larvae can survive for several hours at well below normal brood nest temperature (35℃) therefore the probable cause of this condition will be neglect by the adult and nurse bees in the colony. Death is due to a combination of prolonged exposure to cold temperatures and starvation. Examination of colonies in cold weather isn't generally recommended, but where necessary should not have this effect if carried out without swiftly, nurse bees will quickly return to tend and warm the brood.
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Image Courtesy The Animal and Plant Health Agency (APHA), © Crown Copyright
Chilled Brood (dark in colour), the other brood has normal healthy colouring.
Relatively large areas of dead brood in the brood comb at all stages of development indicate a problem with adults tending the brood, be on the look out for other underlying problems.
Hive Examination - Examination of brood frames and floor debris is required especially in spring. Bees should be gently shaken from the frames to allow full inspection, abnormalities are then easily spotted.
Monitoring - Vigilance is important with all honeybee diseases. Check all apiaries and colonies regularly for health and suspect any colonies that are not thriving where there is no already known reason. Colonies that are not performing well or die out should be examined thoroughly and sealed to prevent robbing and spread of any disease present..
There is no specific treatment recommended for Chilled Brood. Prevention is the best method of controlling this condition by maintaining healthy, strong and vigorous colonies that display good hygienic traits. Always ensure there is enough available food for the colony during periods of bad weather. Good husbandry contributes greatly to overall colony behaviour and health, thereby avoiding the conditions in which Chilled Brood can occur. There is no medical treatment for Chilled Brood. Dead brood will be removed by bees from the cells as soon as the colony grows stronger and returns to normal. Disease prevention is best practice, maintain good apiary housekeeping:
There are no vectors identified for this condition.