Especially when CéDé egg feed is added during the breeding and moulting period in accordance with the instructions. Yet there could be circumstances that could affect the resistance of birds and pigeons, such as draught, temperature changes, illness, stress, flight season, relocation to a different environment (purchase of birds, bird show) etc. In these circumstance birds and pigeons have an extra need for vitamins that improve the metabolism and therewith the recovery of the condition.