I hatched out 21 guineas 2 weeks ago. They have all been healthy and active, but starting about a week ago I have started to loose one almost everyday. They have never gotten wet and have been kept under a heat lamp. They have also had grit from day one. I don't know what could possibly be going wrong. We have had this happen to guineas that we have gotten from a hatchery. The ones that did make it are all very healthy. If anyone has any ideas or suggestions I would greatly appreciate it. Thanks We've been feeding them a 23% layers mash.