Erythrochroism

from The Collaborative International Dictionary of English v.0.48

Erythrochroism \E*ryth"ro*chro*ism\, n. [Gr. 'eryqro`s red + ?
   color.] (Zo["o]l.)
   An unusual redness, esp. in the plumage of birds, or hair of
   mammals, independently of age, sex, or season.
   [1913 Webster]