My ISA girls have all stopped laying. I'm not sure if it's down to decreasing daylight (they are getting 11-12 hours per day at the moment) or if the protein content of their mash is too low. The content of their current feed is 15.5%. Is this too low for them? Maybe the previous owner had a higher content feed. I have had them 3 weeks and they laid for the first two. i am installing an artifical light in the coop today. Please help!!