Maybe the tractor is a Trojan horse?
Bert did just fine at the vet's office. First, he showed up. At the last minute. I was out calling him, getting ready to give up and cancel his appointment, when he bounded over the fence from the woods to our north and came up onto the deck. I opened his carrier and he walked right in. He's healthy, gained 300 grams since last year, got his shots and a worm pill, and that was that.