I need a consult, I need to know if my birds are struggling or on track. They are on free choice grower mash, supplemented with oyster shells and grit. The coop is lighted 16 hrs a day with heat set at 50 degrees because we have already had 20 degree nights. I have 4 that were hatched on 5/6/11 and haven't started squatting yet, but I wonder if they are undersized. Each one is about 3 lbs. These are the ones I am waiting on to lay. I know they are only 20 weeks old, but I am a concerned parent. My RIR My EE My Barred Rock My Brown Leghorn My 18 month old GLW, bought August 6th, waited 3 weeks for an egg she gave us 6 then stopped laying 4 weeks ago. My Lakenfelder hatched February 2011, bought September 3 gave me one egg and stopped. My 2 Bantam Cochins just started squatting today, bought in July (hatch day unknown) and have been a real pleasure. Thanks for all your help and advice. This is my first time with chickens.