Fighting after cleaning?

[Lolo76]

I have two pet male mice (long story, lol), and even though they're both males, they usually get along just fine... but whenever I clean their cage, the younger one attacks the older one pretty violently for a few minutes. Sometimes the attacks are bad enough to leave blood on the other guy! After a few minutes they settle down, and all is well until the next cleaning.

My best guess is that it has something to do with their environment smelling differently - which probably confuses the one mouse, to where he believes there's a "strange male" in his home. Kind of like when you take one cat to the vet, and the other cat hisses at them when you return? Again, the change in smell throws off their familiarity. Anyone know what's happening here, and/or how to stop it? I had an idea of maybe saving a tiny bit of the dirty bedding, and adding that to the new stuff each time. Whaddya think?

[I-KandyReptiles]

I'd separate them.

Males may get along for a period of time but will usually kill each other. At least, that's whats happened when I kept my feeders together.

[Lolo76]

I'd separate them.

Males may get along for a period of time but will usually kill each other. At least, that's whats happened when I kept my feeders together.

I hate to say it, but "separating" them in my case would involve feeding off one... I didn't even want a pet mouse to begin with, let alone two separate cages of them (in addition to my feeder rat colony). So yeah, maybe I'll just wait until it gets to a serious level. They've been together for about 6 months, maybe even longer, and usually get along well.

[Lolo76]

FYI: They were both feeder mice in the first place, before anyone thinks I'm being heartless... the fact that they're still alive, when they were originally purchased as food, means I've already given them a longer life than fate had planned.

[Sita]

I would say you're probably right about the smell thing. Taking away all the scented bedding essentially means the territory is up for grabs, so they fight for it. I'd try what you suggested about saving some the old bedding; just grab a handful and sprinkle it on top after you change it out.

[Diamond Serpents]

This is with 90% of males animals in the world, mice are no different. Its all about dominance, and territory. I would separate them and put them each with a female, before one kills the other. I'm not a tree huger but you are doing these mice more harm by letting them fight till one kills the other, at least one could have been food.

These two males will continue to fight, separate them and if you cant use one as a feeder.

[MrLang]

Feed one off. I think the snake will provide cleaner, faster death than bleeding out from a bad fight.

If there are female mice in the same room I do believe this contributes. Mice stink though, so I wouldn't want them in 2 separate rooms.

[Lolo76]

Well, I didn't mean that I'd wait until they fought to the death!! C'mon now, I'm not that cruel.

I just meant that maybe I can watch their behavior, and try that dirty bedding trick with the next cleaning... and if that doesn't improve things, THEN I'll consider feeding off one or both of them. Oh, and there are no female mice in the household - had one living with them for a while, but she died (naturally) a few months ago.

[BLM94]

Well, I didn't mean that I'd wait until they fought to the death!! C'mon now, I'm not that cruel.

I just meant that maybe I can watch their behavior, and try that dirty bedding trick with the next cleaning... and if that doesn't improve things, THEN I'll consider feeding off one or both of them. Oh, and there are no female mice in the household - had one living with them for a while, but she died (naturally) a few months ago.

In the long run it won't. As others have said, the most humane thing to do for both mice is to feed one off if you don't have the space to give each male its own enclosure.

[Sita]

Is everyone else missing the part where OP said they've been living together fine for 6 MONTHS, yet they only tussle for a couple minutes when bedding is changed?

Granted it IS a bad thing that when they fight, SOMETIMES they draw blood (again, didn't say every time), but if using the old bedding trick works, there's no reason to kill one of them.

I sometimes have a full cage of several male mice that I'm growing out as larger feeders, and I rarely have problems with any fighting, even if I add new males from different cages. My method is that when I need to add ones, I clean the tank thoroughly to get rid of any old scent, then before I put the old and new mice in there, I take a small handful of the old mice bedding AND the new mice bedding (dirty) and sprinkle it throughout the cage. Sometimes there's a brief tussle that is resolved quickly, but most of the time they just run about sniffing each other, then settle down.