Chilled Brood

Causal agent		None
Age group
Egg	Larvae		Pupae	Adult - worker		Drone	Queen
No	Yes (all ages)
Clinical signs
Season		Weather turns suddenly cool. Brood area temperature drops below 35ºC
Outside		None
Odour		None
Brood
Cappings		Uncapped brood on the very edge of the brood nest will not be covered
Larvae appearance		Chilled larvae will die and turn black within 1 day – all ages at same time
Scales (larvae)		Bees remove dead larvae within 24 hours
					Dead larvae or pupae found on the ground outside the hive after a cold snap usually indicates chilled brood. Note ants and birds quickly remove the evidence.
Infectivity
		None
Transmission
		None
Post-mortem Lesions
		All ages of larvae are affected and blackened
Diagnosis
		Note all ages of larvae are affected
Treatment
		Avoid chilling of the hive
Common differentials
Zoonosis		None