This is going to be extremely long winded, but I want to share all the facts before I get some opinions!
 
We have a five year old male named Grundy. We adopted him and his cagemate from a rescue in Pittsburg three years ago. He has always been a very healthy, fat (he was almost 5lbs when we adopted him, he's now down to a trim 3.1lb), and happy ferret. Recently he has had some health issues and our vet diagnosed him with insulinoma, but I'm really not sure about the diagnosis.
 
About two months ago I found Grundy in his cage unresponsive and running a fever of 106.5. I took him to the vet where he stayed all weekend. She gave him antibiotics, sub-q fluids, and got his fever down. While he was there she said he had explosive diarrhea and she took an xray of his abdomen and said his spleen was grossly enlarged. But after the bout of diarrhea he perked right up, his fever resolved, his spleen returned to almost normal and we brought him home and finished out his round of antibiotics. She took his glucose at that time and she didn't tell me what it was but she said it was normal. She wasn't really sure what the issue was, but it wasn't anything contagious because our other two ferrets never had any issues.
 
Four weeks ago I found him again in his cage, lethargic but not completely unresponsive and not running a fever. My husband took him to the vet that day and she took his glucose and it was 53. Of course she immediately said it was insulinoma and put him on pred and sent him home.
 
Here's where it gets weird. Since the day of his appointment four weeks ago, he will not eat his hard kibble. He acts like he wants to. He'll stick his nose in the bowl and nudge the food around, lick a few pieces, but he won't eat it. Every now and then I can coax him to eat a piece but he struggles with it. We give him a bacon Bandit treat about twice a week (bad for them, I know, but he loooooves them) and he won't even eat that now. He will take it in his mouth, walk a few feet, drop it on the ground and then leave it. He's been eating nothing but duk soup, sometimes with some Hills a/d mixed in, but nothing else. We feed them Zupreem which is what he's been on for three years so I thought maybe he just lost his taste for it, even though that would be strange, and bought a bag of Evo. He won't eat that either.
 
He's been back to the vet twice and both times we've brought up the issue of him not eating his kibble and she kind of brushes it aside and says "No, it's not his teeth, he's fine." So we took him to another vet an hour away that is an exotic specialist for a second opinion. She agreed that she thought he had insulinoma because of his glucose of 53, but as she put it he doesn't look or act like a sick ferret. He's doing very very well except for not eating his kibble. We talked to her about that too and she looked at his teeth and said he has some plaque and gingivitis, but nothing more than what would be expected in a ferret his age. We told her we really think he is having some type of tooth/mouth pain and she also brushed it off and said she didn't see anything wrong.
 
So here we are. My husband and I really think that he was having tooth pain and hadn't eaten in a day or longer and that's why his glucose was so low. But maybe he really does have insulinoma as well as tooth pain. We're just stuck, and our vets don't seem to want to address his mouth and he already has diarrhea from eating nothing but duk soup and is now on metronidazole to clear that up.
 
Does anyone have any other advice that we could try? Would not eating for a day or two cause a ferrets glucose to drop like a human's would?

Do you brush his teeth?  It's a good idea to brush them weekly.  We have two that get plaque build up faster than the others.  Have you looked at them?  Some vets will just give a quick look, or not at all.  I have had a ferret that had 3 really bad back teeth.  Mogli's will go brown if he goes 3 weeks without brushing.
Have you tried any other foods?  Ours were eating Ultimate Crunchy for years and they all suddenly stopped, 9 of em.  We have been feeding them Zupreem for years as well and have had no problems with it.  

I will agree about the insulinoma. It can affect appetite, but the fact that he will pick up the food or treats and not eat it is odd.  Has he ever choked or vomited?  Has he lost any weight?  Are his poops normal?

I don't think it's IBD because even with that the ferrets will still eat, and have nasty poops.  I ask about choking because of the possibility of megaesophagus but the vets should have caught that too.  


Just ideas.  

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I'll be honest, we don't brush his teeth very often because he is a heathen and so strong that he will twist out of a scruff easily. We try to do it a couple of times a month but we can never get the tops or insides of the teeth because he won't open his mouth. The second vet we took him to looked at them but said she coudn't see the very back ones because he wouldn't let her and she said it was possible he could have an abscess under a tooth, but normally if that's the case they have facial swelling.
 
When he stopped eating the Zupreem we tried Evo and Marshall food (gross I know, but it's all our pet store had) and he won't eat either.
 
He's never choked or vomited and he has a huge appetite, just not for hard food. He will eat large amounts of homemade duk soup (a whole chicken cooked for 24 hours until the bone is soft, and then puree it all so it's smooth and he gets skin, bone, marrow, and bone). He had lost maybe a pound, I think he was down to 2 but now he's back up to 3 which is normal for him. His poops are pretty bad. He has diarrhea, not really watery but not solid and they are thick. The second vet said he could have an intestinal inflammation and prescribed metronidazole, but I think it's just from his all soft diet. Either way it should hopefully straighten them out.
 
He's going to be on the metronidazole for two weeks, and since it's also an anti-inflammatory we're watching to see if he starts eating hard food again because I would take that as a sign that he was having pain and the anti-inflammatory is helping.
 
But everything I've read about ferret tooth pain says they will usually paw at their mouths, drool, or have obviously broken teeth, and he doesn't have any of those. So maybe we should just keep going with the meds and start tying him up to brush his teeth? lol I'm wondering if we should push our vet to take an xray of his skull to see if that will show any possible abscesses.

I think I would have to go with your vet.....insulinoma.  I would keep up with the preds and switch back to his regular food.

One of my furkids had a abscess tooth.....very easy to identify.   We ended up pulling the tooth.

Poppy had an abcessed tooth that we didn't catch in time and it killed her.  It was a front one too, and we just slacked off brushing for a month and didn't catch it.  Kills me to think about it.
We discovered Eddie had bad teeth because he also stopped eating hard food.  He also got pretty bad and didn't recover from surgery probably due to being weakened.  
Diet change will cause poop change.  I just would't mess around with a possible abcess.  Even if they have to gas him to get a good look.

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Well Grundy had an appointment yesterday, but my husband ended up oversleeping and missed it. He's rescheduled for Tuesday morning and I've talked to him about pressing the issue with our vet. I mean yeah, he probably has insulinoma as much as I don't want to admit it, but there is something seriously wrong if he just one day stopped eating his kibble.

Would an abscess show up on an xray, or would it only be spotted with an exam?

I was able to see the abscess, no x ray were needed for my guy.

Here are pictures of abscess that Zeke had going on.








This is after dental work.

gums would be read and swollen.  and tender to touch

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