D'awww he's so cute, simply adorable! <3 Congrats on your first hoggies!
Now I'm not 100% sure on this since I never bothered to look into it much, but I'll toss this out there for you just in case - I was under the impression that high red/purple/green/white etc etc phases were simply line bred animals. The color of normal wild type hogs is real variable, but if you stick to animals of the highest color only and selectively breed to advance that trait then it'll become much more prominent.
Anyways that's what I've always believed on the matter~
Best of luck with your hog projects! You're off to a great start with that awesome lil' guy!