*Color variety originally created by Jean Ribbeck
Are you interested in learning more about how the chocolate plumage color is created?
Chickens have 39 pairs of chromosomes.
They have two categories of chromosomes known as:
1) Sex chromosomes
2) Autosomes
SEX LINKED RECESSIVE CHOCOLATE:
Sex linked recessive chocolate (choc) is found on the sex chromosome. A male must have two doses of the chocolate gene to express the chocolate plumage color and a female must have one dose of the chocolate gene to express the chocolate plumage color.
The chocolate (choc) gene operates in the following way:
Chocolate x Chocolate= 100% chocolate
Chocolate male x Black female= Black males that carry one copy of the chocolate gene and chocolate females
Black male that carries one copy of the Chocolate gene x Chocolate female= 25% black males that carry one copy of the chocolate gene, 25% chocolate males, 25% chocolate females & 25% black females
Black male that carries one copy of the Chocolate gene x Black female= 25% black males that carry one copy of the chocolate gene, 25% black males, 25% black females & 25% chocolate females
Black male x Chocolate female= 50% black males that carry one copy of the chocolate gene & 50% black females
*Any black females produced in a chocolate project pen do not have any copies of the chocolate gene.
Our chocolate Ameraucana are created from the sex linked recessive chocolate gene!
DUN:
Dun (I^D) is a gene that is autosomal and also used in some breeds to create brown plumage color. An autosome is simply defined as a chromosome that is not a sex chromosome. An autosomal gene always comes in two doses (one dose from each parent). Dun is an allele of the dominant white gene (I). If you are familiar with how the Blue (Bl) gene operates, the dun gene operates in a similar way.
In its heterozygous form (one copy of the dun gene, known as I^D/i+), black feathers are diluted to create a light chocolate plumage color. In its homozygous form (two copies of the dun gene, known as I^D/I^D), black feathers are diluted to create khaki plumage color. The genotype for the non-mutated version is i+/I+.
Hopefully this educational post will help you as you work with the chocolate project color!
