I inherited an old "feather ticking" made with downy feathers as the lining from my mother-in-law when my DH and I were first married. I have stored it in a cedar chest all these years. It is in dire need of repair and I did not have the heart to throw it out.
I think that if the feathers are the real downy feathers (the softer ones) and dry, they would work in a quilt.