From what I understand, that is quite common in male Hognoses... that's actually one reason I got a female, since I was warned the boys go off feed in winter. Not sure what else to say, except that you shouldn't worry too much - unless he starts looking extremely thin, or doesn't go back to feeding in spring.

P.S. They do supposedly have a thing for toads & frogs, so if all else fails, you can rub a mouse on a toad... that sounds so funny, LOL.