I have 8 chickens that are 4 different breeds. They are 17 weeks old. One laid an egg (first egg of the flock) yesterday; a small one but perfectly fine. They are still eating Grower feed. I have read that Layer feed can cause health problems for those not laying. I am wondering how I need to feed the flock with one egg layer. Should I continue finishing the Grower feed until more are laying, switch to layer feed or mix the two?