Thank you for waiting. Your conditions are all good, so that isn't likely the cause of the problem. You might try to get the very warmest spot in the cage up to about 95*F. Sometimes being just a bit warmer can increase appetite and activity level.
It is normal for a snake to stop eating and become less active before a shed. However, the skin should soon turn translucent and the eyes cloudy. Other signs of an approaching shed include rubbing on objects in the viv and spending more time in the water bowl. It is possible that the snake is getting ready to shed. However, it is also normal for bullsnakes to go through a less active phase in the winter, even when they're in a warm home. A snake can go for several months without eating, so you don't have to worry yet. Keep a close eye on him. If you notice him breathing with his mouth open, making a noise when he breathes, slobber coming from his mouth, discharge from the eyes or nose, swelling anywhere on the body, blistered-looking skin, or total inactivity, it would be best to consult a reptile vet. Otherwise, skip a couple of feedings before you try again. If he still won't eat, again, it might be best to see a vet. If you go to this site and scroll down to UK, you'll find a directory of reptile vets:http://www.anapsid.org/vets/index.html#vetlist
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