Something that happened to my father

So I am from Romania. We have a thing that we kill our pigs every time around Xmass. So this one time (some years back) my father and 3 other people came to sacrifice our big ass lady pig (it had around 200 kg which is hella big). They put it down on the ground, held the legs and such and father took the knife to its throat. The thing is, just as the pig felt the pain, jolted up and shook all people off of it and bolted; broke a fence in panic and ran for the woods, with the knife still stuck in its neck. They tried to give chase but to no avail. There was no blood trail as the knife acted as a cork. Now, after 2-3 years, my father went to the woods to gather firewood. He said he thought he had heard a boar of some sort. Looking closely, it was our swine that escaped the sacrifice and it still had the knife in its neck. But this is not all. The swine was being followed by 5 or 6 piglets. And every one of them had a small knife stuck in their neck.