I killed an embryo, thinking it was a quitter. I always do autopsy's on every egg I throw out and this one had a living, breathing and kicking embryo. I was so stupid! i feel horrible. But one thing intruiged me, black down was forming. and this was a RIR/RIR+leghorn egg. the father was a cross between a leghorn and a RIR and the mother was an RIR. do RIR's have a recessive black feather gene?