Dyes for birds.
To keep our red factor birds in colour we need to give a supplement frequently to promote the pigmentation. A good example is the red intensive canary.
Without an additive of canthaxantine it is difficult to get these birds at colour.
A canthaxantine food dye is potentially liver toxic to birds and must always be used in accordance with dosage calculated by experienced Avian nutritionists or breeders. Add colour intensifying supplements with caution.