Re: should I be concerned?
Do you know what his weight was before he went on his hunger fast and what it is now? Does he look emaciated? At his age a four month hunger strike shouldn't be life threatening if he was at a healthy weight to start with. Try misting his cage twice a day to help keep humidity up. Also, just for reference what are his temps? Hot side and cold side? It sounds like one of the live rats took a strike at him. I would suggest switching to f/t if at all possible. I tend to only feed hatchlings live and then once I've gotten some weight on them begin the transition to f/t. It is less dangerous for the snake. Believe it or not but some snakes will actually fall victim to live rats.
Also, he could be a mouser. Try offering some mice and see if that breaks his hunger strike. If a rat took a strike at him he might not be interested in them anymore, and you might have to go back to mice.
Finally, two to four weeks is too long to go between feeds in my opinion. My adults get fed every 7-10 days depending on the snake, but never longer than two weeks. Four weeks should definitely not be held as a standard amount of time between feeds for a healthy adult. Once you get him eating again I'd try feeding more often.
Re: should I be concerned?
You can always try offering some mice again to see if he will take them. If he takes them, feed mice for a few feedings, then try offering a mouse and a comparably sized rat. But, as TexanLady said, he may have decided to be a mouser.
Re: should I be concerned?
Thanks for the suggestions! I mist at least twice a day, usually more. Hot is 90-93, cool is about 80-85. We've always just fed him when he seemed to start to get active and on the hunt again, which was always about 2 weeks after his last meal, but sometimes up to 4 more recently (I assumed it was the larger meals).
I dont have a scale, but he definitely is not emaciated. He is still thick and strong, and he is drinking well. I thought his nose looked a little raw, and I snapped a photo, but I can't get it to upload from my phone. I will try a mouse and see if he prefers that.
Re: should I be concerned?
Yeah, it sounds like a rat took a swipe at him, and now he's scared of them. It happens with live from time to time. As rats get larger (older) they get more aggressive, and can put up quite the fight. Try mice. I bet he snatches them right up.
Re: should I be concerned?
I just wanted to update and say that George took two mice. Practically snatched those little things right out of the air. Guess he prefers mice to rats.
So, what should I do to keep him healthy when he doesn't want the larger meals for his larger size? I was told line feeding was bad, which is why we switched to rats (he was eating 4 mice at a time).
Thanks for the advice so far (and in advance). :)