No I have not, nor would never kill an animal. I am not vegan, but strive to eat open range and naturally raised meats.
I had gotten a rescue from the local ASPCA. She'd been removed from her owner for abuse and they knew we had experience with her breed. I cried when I first saw her, and for many nights after until a year later she was full fleshed out and healthy and happy.
Long story short, we had an encounter with her previous owner. It was 11:30PM, I was alone and 8 months pregnant with a huge puddle of terrified dog at my feet. What do you do then? I exploded on this hulk of a drunk SOB. He made a move for me and that dog made her choices.
It ended when I told him I didn't know how long I could hold the dog back....but she'd gotten her evens. We were both satisfied.
It was quite the experience! That dog was never the same. After that she was a very self confident dog, and absolutely devoted to the baby and I. Her horrid treatment, the lack of nutrition, the physical aspect of it all claimed her early as it did your boy.
But...at least she got her evens.