duck eggs for her. I currently have 40 EE eggs in my incubator, due March 31- april 1st. I don't want more chicks at that point, as long as some of these hatch of course. I have some duck eggs collecting in a nest in teh duck house, I was hoping one of the girls was gonna get the mommy bug but she hasn't. would any of those eggs still be okay to throw under a hen, it's still cool enough outside, how long are duck eggs okay before viability for hatching wanes off? I would hate to have my hen sit for 28 days and hatch nothing. as well, how many duck eggs can a hen comfortably sit on? She is a buff orp/leghorn cross.