i have been feeding Layena to my hens. Then i got ducks and geese and they get Flockraiser. Couple times i've run out of the Layena and used the Flockraiser for the chickens and they seem to like that better. i know it's higher in protein and does not have extra calcium, but if i supplement with the crushed oyster shell, wouldn't that be sufficient? Just wondering if there could be any problems with feeding them the Flockraiser as their main diet.