Two thoughts: 1. I'm not sure we've tried. Maybe it's possible, but we've never tried. 2. If we have tried, and it hasn't worked, it's possible there's not en

Two thoughts: 1. I'm not sure we've tried. Maybe it's possible, but we've never tried. 2. If we have tried, and it hasn't worked, it's possible there's not enough genetic diversity in pigs. Dogs have an enormous amount of genetic diversity, which is part of why we've been able to get breeds that look like entirely different species. There are many breeds of cats, but I haven't seen any that are as radically different as, say, a chihuahua and a mastiff. We bred tame foxes, but they weren't radically different from wild foxes. (The different physical traits, I think, were their ears were floppy, and some retained juvenile markings into adulthood - similar to dogs.)