Originally posted by knighttemplar1960:

According to the wiki the game gives a 50/50 chance of the offspring having the same star level as either parent. I haven't done any experimenting with disparate star level livestock to confirm or deny that as yet.

Now I'm interested to see what happens when you breed a 2 star with a no star.

You get either a 2* or a 0*.

I haven't conducted any detailed studies, but the 50% probability for each seems reasonable from my experience.