I have just come across this and the post has called my name. We dont have Hereford mice in Australia although look a likes are out there for example AW Dahla when she was a baby
and I currently bred her to another simalar face marking buck and Dahlia had a marked black and white with a tan/white marked belly and the othere was a black headspot actually 3 one on his face one on neck and the other on her back also a berkshire belly white markings.(could also be a irish spotted).
I will get photos of everyone if interested. I am trying to breed the face markings like the hereford.
Some help would be awsome

and I currently bred her to another simalar face marking buck and Dahlia had a marked black and white with a tan/white marked belly and the othere was a black headspot actually 3 one on his face one on neck and the other on her back also a berkshire belly white markings.(could also be a irish spotted).
I will get photos of everyone if interested. I am trying to breed the face markings like the hereford.
Some help would be awsome