Question: I'm trying to find out if there is a genetic reason for stray white hairs in black rabbits (New Zealand Black)? I have two youngsters that just developed patches of scattered white hairs (enough for a Disqualification DQ on the show table). I had high hopes for these two because of their body types - but don't want to perpetuate the bad color if it's genetic.
Answer: The Stray White Hairs (SWH) are a genetic issue. I believe the stray white hairs are a separate gene.
It is not caused by breeding to Ruby Eyed White (REW) unless the REW happens to have the SWH gene, which would be hidden under the white coat. Some Black Dutch rabbits will have SWH. Dutch are NEVER bred to REW. Some breeders will use tweezers to pluck SWH before a show although it is against the rules.
Stray White Hairs are an issue in American Blues, which has been fighting SWH since the beginning of the breed in 1917. The issue can be improved by breeding away from SWH, only breeding those rabbits with excellent body and fur and minimal SWH, to overcome the SWH fault.
I believe most of the breeds with solid colors recognized have a Fault for stray white hairs which becomes a disqualification (DQ) if 3 white hairs are found together in a colored fur area. My advice is try to find mates that do not have SWH to breed to the youngsters with SWH. Then maybe you can get some offspring with the body type and less SWH.
Have a good day!