I adopted Zeke a few weeks ago. He's around 13yrs old and was drastically underfed. The previous owner only fed him 3 small mice every 2 months. He was fed those 3 mice the day I got him. Two weeks later I fed him 2 small rats and did so again last Friday. I've handled him a few times and noticed that his skin folds up when curls up. I have a student who's BP is younger, but twice as thick according to him.

How can I help Zeke gain some weight? Do I maintain my new feeding schedule of 2 small rats every 2 weeks? Should I start feeding him more often and keep the same amount of food? Should I keep the same time frame, but feed him larger feeders? His girth would dictate a medium rat, but his neck is so small I'm afraid of feeding him something that large.

TYIA