Thanks!
Dwarfism is a recessive trait so you breed a dwarf to a standard size rat and hold back the females as they will carry the dwarf gene.
Then the dad back to the daughters for half dwarfs and half standard size.
I have been breeding dwarf to Black, Siamese, Blue Agouti and Blue females
My Black and Blue standard size rats carry Siamese as does my black dwarf.
My male breeder is a double rex which is why I place him mostly with standard coat females to make 100% rex coats.
This is him as a youngerster
And now as a multiple time proven adult dwarf
For a size comparison ~ This Blue Hooded male is about the same age
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