That's good information to have. So having an unicorn in the household can also be held because of the strategy: no training required for the offspring, but you can sell it high right from the start. It saves money.
Oh, and welcome to the forum by the way.
Yes, you can focus on training up whoever you're breeding it with instead. The only downside is sometimes you get a unicorn, but that's not really so bad, and it looks (tentatively for now) as if having some unicorn blood in there might increase the value a bit over a pure horse foal over and above the skills component, but I'm going to check that with duplicate traits to be sure.
Thanks for the welcome
This is definitely the expansion I've been waiting for, so much better than previous efforts on pets. I'm looking forward to playing as the horse next to harrass people for carrots like they do to my poor sim!