Hi everyone thanks in advance for the help, here's my situation!
 We got a little baby, Eugene about a month ago. He was VERY young when we got him and clearly still teething. I mention this because the first time I saw his aggression was with things that he'd chew that clearly helped his gums. I let it go for that reason. I saw it again when he had just woken up and was hungry, I let it go again knowing how crumby the conditions must be for them in pet stores/the big breeder and maybe he just wasn't used to having all the food he needed.
 But now he's getting bigger and it's getting worse, it's not just nipping or hissing he FLIPS out, growling and thrashing around even after I've scruffed him.

Everything I read only addresses nipping or "territorial" behavior. But just today I was giving out treats and he came running up, being very pushy and not in the mosey ferrets way, he was being quiet nasty. He hissed when I wouldn't give him the treat right off (I don't reward rudeness!) and I tried to place him back to hand him the treat and he thrashed, trying to bite me while hissing and groaning and his body was very stiff. I put him in a different part of the room and he kept coming up being really aggressive towards me and another guy. I couldn't simply, push him back, cos he'd try to attack me. Then I put the treats away cos it was getting too nasty and his behavior carried on to playing with the toy and it took a while for his grumpiness to wear off and for him to relax.
 The thing is it's not all the time, at times I can feed him from my hand and everyone can be around him, or sharing a toy, other times he can't stand sharing or being touched. Even though I'm the one handing him the treat!
 This seems beyond normal greediness and grumpiness and really am having trouble finding a solution. It's not "cute hissing" he's violently lashing out like a mean little leopard/snake ferret baby.  Thanks guys!

Here is what I would do in your case. I have a ferret room, where I can block it off. I would keep the little one separate from others in this room. Let him run off some energy. (hour or two) Then it's time to bond with mom. I would spend time just him and I. I use a big stuff animal to block him if he decides to bit. Depending on his behavior, will tell me when he is ready for rest of the house. No treats! I hope this helps and good luck

He needs to be taught some manners.  We hand out treats as soon as they've finished their soupies, but I agree with Wen, Eugene should earn treats by being nice.

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