how long til lice eggs hatch?

[winecountrychic]

7 days ago I noticed lice on my 3, 10 week old chicks. I dusted them with poultry dust,changed their bedding and dusted their coop and I haven't seen any lice since. I went ahead and dusted them again today since it has been a week. They have alot of sandy looking grit stuck to the base of their feathers which I assume are the lice eggs and I was just wondering when they will hatch so I can kill them.

 

[Judy]

Usually it is recommended to wait 10 days then dust again, as the eggs will have hatched by then.