Ok so here's the deal. I got a bunch of RIR's, Boschvelds (SA breed) and a pavement special - all hens. I have 6 roosters - 2 RIR's and the other 4 are dodgy pavement specials and the whole big happy family all free range together. I want to incubate and hatch some real dinkum RIR's so I plan to put a couple of good laying RIR's hens in their own enclosure with my fabulous RIR rooster. How long should I wait before using the eggs for hatching. ie: how long to make sure I'm not going to get eggs fertilised by the dodgy roosters?