One of my new piggies, Blizz, appears to have a swollen foot on his hind-leg. I've only had him for a little over a week and I'm not sure when this developed. There doesn't appear to be any cuts or injuries other than the swelling. Any idea what this could be. I'm going to keep an eye on it and see if it changes. If it gets any worse I'll be taking him to the local vet on my next day off. But any advice or insight would be appreciated.