VJ, there is a possibility of gout if the roos eat the hen's laying feed. They do no lay eggs, so it builds up in their bodies. The problems can occur also if the roo is getting high protein and extra salt, as i understand it.
I never even knew birds got gout, until i reccomended someone to feed canned fish to give their birds a boost in the winter! (both high protein AND the salt) whew. I was corrected..........So all in moderation, i guess. I just want to let people know the possibilities, just in case.
I have not tried purina flock raiser (I do not like purina and do not trust them, i fed my cat it for many years and last year he started puking, every time i feed him any kind of purina product, wet or dry, even labled different, every kind of purina owned food sickens him.

) Needless to say, i have a mistrust. Kinda stinks, because the fancy feast chicken and liver was his favorite treat. (owned by purina, still makes him sick)
I am an odd one out, i feed the
manna pro showbird formula to my birds, it is a concentrated pellet feed that you give 1-2 Tb per bird, then i supplement with oyster shell and as much scratch as they want. I have tried other brands flock raiser, even the kent, and though i supplemented with oyster shell my hens got thin shells. Don't know why, i don't know anyone else who has this issue.