Yes, providing you've been shown by a competant person (ideally a vet or experienced breeder) and you're doing it before day 5 of life - you'll not be breaking any laws.
We do all our 'big' pigs (Large Blacks and OSB's) ourselves, usually on day 3. I hold them while Bruce does the deed itself

Angle bum downwards (piglets that is) and slit the scrotum, gently pop the testicles out and cut the connective tissue, repeat on the other side then give a good squirt of antibiotic/antiseptic spray. The piglets make more noise being picked up then while it's being done and are back to mum within 5 minutes and really don't seem any the worse for it. (I couldn't do it otherwise

) We run all ours in big family groups so this is a surefire way of making sure we don't have any accidents

I can also detect boar taint/smell/whatever you want to call it in the meat, so from a personal point of view I'd rather they were castrated.
But, we don't do the Kunekunes ourselves. Firstly, trying to find a Kunekune testicle at 3 days old is almost impossible

and they run a far higher risk of herniating during the proceedure because of a weakness in their inguinal ring. So for them, they go off to the vet at around 6 weeks old and have a closed castration under anesthetic just to be on the safe side

I do know some folk who castrate Kunekunes themselves and haven't had problems but one of our very first litter herniated while getting done at the vet first time round, if he hadn't been there he'd have been dead

that's kinda reinforced the vet for Kunekune castration method in my mind.
HTH
Karen
