Is it ok to keep feeding my girls (3 Welsummers...2 laying, as of today) the grower I have? I'd like to use it up before I buy layer for them; they get kitchen leftovers every day...and spouts every other day. Egg shells are dried, crumbled and thrown in with the scraps. Grit is freely available. So, are they getting enough protein? I got my first egg Christmas Day and since day oe the eggs seem to have a nice, hard shell...is this how to tell they are getting enough protein?