I've had ferrets for just about a year now...
2 boys: Dante (4, big, albino, being aggressive) & Bandit (4, blind, IBD, cancer, gentle as can be). 2 girls: Enix (1, crazy, naughty, adorable) & Khaleesi (found outside 4/3/14, seems under 1, timid, sweet)

Dante has always been aggressive when he plays, which is why I adopted Enix....Bandit couldn't handle him. It worked out great, but lately Dante has been grabbing Bandit by the neck and shaking him as hard as he can. Then Bandit screams and seems terrified (I mean...he's blind. He doesn't see it coming) and he follows Bandit, often having to be separated long enough to calm down. Scruffing doesn't help. He does the same thing to Khaleesi and seems to be doing it more since she was brought home. He very much wants to mount her, which he has never done to Enix. He's even more aggressive in his play with Enix lately. Enix is definitely fixed, as are Dante & Bandit. I have no idea about Khaleesi's history. She was very thin and exhausted when found in the snow. 

Is this just a male thing? Should I be worried? He seems very healthy....he's a big ferret, he plays with me, he gives lots of kisses and he seems to understand that the food area, cage and litterbox are off limits for biting the other 3. I am just constantly "saving" Bandit and Khaleesi, especially Bandit when he's trying to sleep on his bed. They all cuddle in the cage without issue, and outside of the cage when Dante isn't feeling playful. 

Dante has, at times, gone after my cat. He seems to think it is fun. But one time my cat tried to bite me and Dante ran, out of nowhere, and chased my 20+ pound cat out of the room for it.

It sounds like he is an alpha ferrets. Which is a trait that you can't remove even with training. All the alphas I have come across only do well with other alphas but will bully and injure other ferrets. It is probably best to separate him from them to prevent harm. I've had an alpha cut open another ferret to the point of needing stitches. 

Are you sure about separating? They've been together (except Khaleesi) since August of last year and I've never found a single scratch on Bandit. It has gotten worse with Khaleesi here....which has me nervous since she has no ear tattoos and was found outside, I have no guarantee she is spayed. She's still trying to get to a healthy weight. She doubled her weight and is now at .69lb

She could also be a triple f ferret. If not she could be from a back yard breeder or a certified breeder. If you notice any marks on your smallest one then separation might be needed. It could just be your alphas way of initiating her into his pack. But if he is constantly bothering her then her safety is a must. If she starts showing signs of going into heat then it means shes around eight month old. You will have to take her to the vet for a jill jab. 

I'd only separate them if there was vicious fighting.  Jaffa is a big ferret, and back when he was being a bully, it WAS scary and he did have to be separated.  BUT, that mostly involved Prissy, an alpha female, and my 5 ferrets when he first met them.  He grew out of it.  4 seems a bit late for him to be going through a dominance phase, esp if he's been with the others for some time.  My only guess might be adrenal disease, which can cause both sexual aggression and general aggression.  Dos he have any other clinical signs of adrenal?

THE DOOKS OF HAZARD

I've been keeping an eye on Khaleesi for signs of going into heat. She has her first check up next week. All I could get her in for so far is a microchip scan before I officially claim her as mine. She's the only one he has ever tried to mount. He was immediate best friends with Enix, and she's still his main playmate. He doesn't seem to care for toys...even got a ball pit and he doesn't care.


I worried about adrenal disease as well... but he isn't losing his fur. He's actually ridiculously fluffy! And he's a beefy, solid ferret, so no weight loss. Sometimes I think he's just bored, but even lately with Enix, he makes her yelp. She can get free and she chases him around so she can't be too upset, but Bandit has ended up chomping into my hand when I separate them. Then of course he gets upset because he didn't mean to bite me, just thought I was Dante. Khaleesi runs into the cage or up on the couch with me (or else I go separate them), and he leaves her be. It's like he has designated "safe zones" for them or something. 


Do you diagnose adrenal disease with a simple blood test? He's due for his annual check up after Khaleesi gets hers. He's actually overdue since Bandit needed a biopsy earlier this year.

Unfortunatley, the blood test for adrenal is neither simple nor cheap, nor is it 100% conclusive.   In the US, where AD is more common than UK or Australia (you didn't say where you are) a ferret savvy vet will diagnose on clinical signs and not make you pay for the Tennessee Panel, a blood test that checks levels of certain hormones.  If you have researched the signs, you may be aware that each ferret presents differently.  If you see any 2 of them, it's a good bet it's adrenal.  
I had thought that Triple F tattooed their kits, but I may have been thinking of Path Valley.  

THE DOOKS OF HAZARD

Hmm. I will talk to her at Khaleesi's appointment next week. 

I'm in the US. I wonder if I can find out online who supplies most ferrets in Minnesota and North Dakota (I'm on the border). Khaleesi is very small...so I have a hard time guessing her age. Enix is very petite, but she's over a year. Khaleesi does seem younger.

so I have a hard time guessing her age.

Check out this thread - Teeth and Aging

http://forum.ferret.com/tm.aspx?m=129254

I hope this helps.

It's more figuring out if she's under 1 that I'm struggling with. I feel like she's 6-7 months old, but I can't be sure. Everything seems to go from a few weeks old, then jumps to 1 year. Her teeth are very white, and she's a very tiny girl with large paws. 

Starting to wonder now. Whenever I'm holding Khaleesi and I pick up Dante, Khaleesi lunges at him, trying to bite his face. Yet whenever Dante walks up to her when I'm not holding her, he tries to mount her (biting her neck and climbing on top of her).

I feel like maybe this has 80% to do with Khaleesi and 20% Dante's already somewhat aggressive nature. 

Is this a sign she isn't spayed, or not? I've never been around a ferret that isn't fixed. And I've always thought and been told my others that my ferrets are much nicer than most (or maybe they've just only met rowdy ones).