I switched the 17% layer crumble with 3.8% calcium to 30% protein game bird chow. I'm noticing the colour of some eggs shells are light brown not the usual dark brown egg shell colour. They have supplemental oyster shell in their coop. Should I be concerned?ed I made a little warm mash(a little cold outside) for them too with finely ground up oyster shells mix with wheat bran and cracked corn...just to get the calcium in them. what do you all think? maybe i will just feed them a few leaves of kale it has calcium in it as well. I like the way the birds are doing on this 30% game bird feed...it has less fat than their previous 17% layer crumble.