I would also add that some years ago, we were adopted by a cat which had belonged to neighbours a few doors down. They emigrated to Australia and left him behind. We came in one bitterly cold night to find him on the roof of our garden shed, miaowing pathetically, so we brought him in and fed him tuna (we didn't know he had been abandoned at that point). A couple of days later, he reappeared in the garden crying and in obvious pain, so I rushed him to the vet, who said he appeared to have been hit by a car and had a broken pelvis. He never left us and went on to live a happy life with us for another 12 years. I will never understand how anyone can simply abandon an animal.