Agouti (coloration)

Agouti is a type of fur coloration in which each hair displays two or more bands of pigmentation.

This effect produces a very distinctive, finely "speckled" appearance similar to "salt and pepper" hair, as well as an iridescent effect very similar to shot silk which causes the overall color to appear to shift subtly depending on the angle of the light or when the animal moves.

In dogs, there are four alleles on the agouti locus with the hierarchy of dominance (epistasis): Ay, aw, at, a.

[4] The alleles Ay, at and an are not present in wild wolves that have no domestic dog among their ancestors.

[5] In fancy mice, there are eight common alleles on the Agouti locus with the hierarchy of: Ay, Avy, Ahvy, Aw, A, at, a, and ae.