Hi everyone! As a potential breeder of separate lines with both colour and ratings, it's primarily a colour question. How do I know the genes are homozygous and if they are not? I couldn't be clear on whether it's E.g. SplSpl or Splspl?

There are two ways: Take a guess based on the pattern the horse has (for example, badger face aka 'reverse blaze' = homozygous sabino), or gene test the horse. Gene testing is much easier if you haven't been looking at patterns long enough to tell the difference between heterozygous and homozygous.

You can tell if a horse is homozygous in a trait just by looking at the pattern variation, but learning all variations takes a while. I'd recommend gene testing your horses in the vets office to find out their genes.

Thank you guys! :D