Fawn-2: A dominant plumage color mutation in Japanese quail

Abstract

A plumage color mutation fawn-2 in Japanese quail (Coturnix japonica) is controlled by an incompletely dominant autosomal gene allelic to and incompletely dominant over the yellow (Y) gene. The proposed gene symbol is Y12. There is a high possibility, however, that the fawn-2 is a recurrence of the previously reported fawn mutation. Another possibility is that the fawn 2 may be the third mutant allele at the Y locus. The fawn-2 chicks show a creamy yellow color all over the body with three dark stripes on the back The stripes are clearer in the heterozygotes than in the homozygotes. Adult homozygous males have a rusty face with the crown composed of dark and creamy feathers and show a whitish light-brown color all over the trunk with a few small black speckles on the back. Adult homozygous females show a more creamy plumage color than the males and have a relatively large number of small black speckles on the back. The primary plumage pattern is basically the same between the homozygotes and heterozygotes in each sex, but the heterozygotes show a deeper brown color than the homozygotes. The amount of the black speckles on the back is similar between the homozygous and heterozygous males, but that is much larger in the heterozygous females than in the homozygous females.