1 year old male suddenly turned picky aggresive

by Bucksforever Sat 29 Sep 2018, 12:25 pm

Hi everybody!

I joined this forum because something kind of weird is happening with one of my mice, and I need to help him.

I currently have two bucks, Curry and Gratis, which are siblings and 13 months old. When they were 1 month old they were rescued from an animal facilities where they lived together, but have been living separatedly since they were 2 months old, as Gratis started to chase Curry and bullied him all the time. Both cages are in the same room, as our apartment is quite tiny.

After separation, both of them soon turned really tame, playful and affectionate both with me and my boyfriend. Everyday, they enjoyed separate playtimes on the couch, where we provided them with toys, mazes, etc. They loved to be pet and kissed, they never bit any of us and they ran out of their cages and literally jumped into our hands as soon as we opened their doors.

But 2 months ago, Curry, the tamest of them (and the submissive to his brother Gratis) suddenly started to behave aggresively only towards me. The first time he bit me, we were going through a heatwave here in Spain and I was petting him in my hands. I didn't give much importance to it, as there was no blood spilled and I supposed it was only his way of telling me "hey, get your hot hands out of me". But now weather is cooler and he keeps doing that... only to me! Crying or Very sad

This is as it happens: I open the door of his cage, for playtime, and he eagerly jumps into my hand. I gently put him on the couch and let him play alone of climbing on me while I sit there. He is always the first one of the two to come out for playtime as I don't want him to smell his brother's odour. Altough I must say he has recently started to poo on the coach's arms, something he didn't do since he was really young.
Anyway, after a while of playtime, I try to grab him to get him back into his cage. I have always used the cupped hands method. Once he has willingly jumped into my hands, I lift them so as to get him back home and then, without a warning, he bites me quite hard, making me bleed. I try not to release him inmediately, but it's difficult since it's quite painful. The shocking part comes when, seconds later, my boyfriend does exactly the same as I and he never gets bit. Shocked

I don't really understand what could be happening. He is in a superb health state and doesn't seem to be experiencing any pain or illness at all that could be discomforting him. I always handle him with washed hands, so he can't smell his brother.
I want to help him as I am starting to fear him and the coming-back-to-the-cage moment.

What could I do? Thank you in advance!