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Hand Rearing African Grey Chicks

This blog will detail hand rearing of two African grey chicks. You may read about their parents and the clutch  here . The two chicks hatc...

4.5 The Dark Factor

The dark factor gene is an incomplete dominant gene that causes the darkening of the melanin (blue/black pigment) in birds. Since the gene is incomplete dominant, two dark genes (DF) have a greater effect on the bird than a single dark gene (SF). To understand the effect of the dark gene on a bird, imagine that you put on dark sun glasses and look at a normal green bird. The green appears darker and the bird is called dark green. With a double dark factor imagine that you are looking through two pairs of dark glasses. The bird will appear darker still and this colour is called Olive. Similarly if the bird is a visual blue, a single dark gene causes the blue colour to appear darker and the bird is called a cobalt. Two dark genes further affect the blue colour and the bird is called a mauve. The following table shows the effect of the dark genes on green and blue birds.


In our markets a grey-green is often wrongly called an olive. Please note that an olive bird is genetically very different from a grey-green bird (and much more valuable). You may visithttp://bestofbreeds.net/wbo/budgerigarcolourguide.htm to see the difference in colour.

Let us work out a sample pairing.
Dark Green Split Blue X Sky Blue

We get
25% Green Split Blue
25% Dark Green Split Blue
25% Sky Blue
25% Cobalt

Try the following pairing
Mauve X Green Split Blue
4.5 The Dark Factor 4.5 The Dark Factor Reviewed by Unknown on 04:19 Rating: 5

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BirdTalk.org is my blog on keeping and breeding Congo African Greys, Alexandrine parrots and Cockatiels. The BirdTalk discussion forum can be found at forum.BirdTalk.org