hormonal agression

I adopted Thom and his littermate Finn (both est. 13 mos. old) from a rescue shelter about two weeks ago. Thom was flagged as a potential biter, though the seemed ultra-friendly at first and constantly begged to be picked up. I did note from the outset that he had balance problems and was...

My dude mochi has hormonal aggression.. He doesn't play nice with other rats so he has to be on his own, which he actually prefers anyway because he gets a lot of personal attention.... I had a question about when he gets hormonally aggressive... Obviously if I rile him up he will bite my hand...