Please think twice before feeding them wild bird seed at all. Everytime I fed mine wild bird seed, somebody died. After the third loss, I figured out what was doing it. I've never given them bird seed again and that stopped the loss.
The bird seed I fed them was not a cheap food. It is Mayo Wild Bird Seed. It doesn't have a lot of millet in it, which are the seeds even wild birds don't eat. It does have peanut hearts (little tiny pieces of the heart of the peanut) in it. Perhaps that is what killed my quail. I don't know. But I do know it isn't worth the risk to me.
Good luck with yours!
Hope y'all have a TERRIFIC EVENING!!