Why doses the pig only have one leg?

A travelling salesman came upon an old farmer sitting on his porch, next to the farmer was a pig with only one leg. The salesman was about to give his sales pitch when his curiosity got the best of him. “Excuse me sir, but why does your pig only have one leg?” asked the salesman. “Well sonny, I’ll tell ya. One day I was out plowing the back 40 when my tractor overturned, pinning me underneath. I was losing blood and thought I would die when that pig came running. He dug and rooted around with his nose till he got me out and he dragged me back to the house. Saved my life that pig did.” “Wow, that’s really amazing,” said the salesman, “but I still don’t know why the pig only has one leg.” “Well, I’ll tell ya,” said the farmer. “One night me and the wife were asleep at about 3am when a fire broke out in the kitchen. Well that pig broke down the door, came into our bedroom waking us up and getting us out before the fire could get us, saved our lives that pig did!” “Well, that’s really great but why does the pig only have one leg?” “Well sonny, when you get a pig that smart, you don’t want to eat him all at once.