castrating male p.b. piglets

Question
I have 3 pb pigs, one of which is a female, she recently had a litter and today when we were castrateing them , 2/3's intestines came out and could not be fixed. My boyfriend castrtated them as he lived and worked on a pig farm all his life and he said that he had seen a pig do that only once before and not twice in a row. im wondering if the males should have something to knock them out beofre this is done? He castrated the last litter she had and they were both fine? They are 3 weeks old this time however so im wondering if maybe that had something to do wiht it as well.  
Thank you for any help.

Answer
Thanks for an easy question!
Inquinal (scrotal)  hernias are a common defect in potbellied pigs, more  than in farm pigs.
In fact, THE most common genetic defect.
Because of stress, and the chances of these hernias, potbellied pigs must always be put under anesthesia and neutered by a vet. The vet will put sutures in the inquinal ring if it has not closed (that separates the scrotum from the abdomen).
(Age has nothing to do with the hernia).
The chances of this happening if you use the same parents again are high.
Good luck,
Priscilla Valentine
www.valentinesperformingpigs.com