Hello! I have recently started hatching quail. But the thing is they keep dying. I have done some research and observations leading to this event so here they are. The food brand,not being strong enough to hatch from the egg without help,and possibly the egg sac. The reason I say the egg sac is because 2 of my quail had hatched with their egg sac and later died.
I'm not exactly an expert on quail considering I just started hatching them. But I hope I was able to help a little!