Hi all I got in 3 rescued female rats about 9 mos old, from a hoarding case where they were not properly fed nor housed. they are curious and active but not fond of being picked up. I've been working with them for just under a month and they are making great progress. last weekend I brought home a neutered male foster, who was from the same hoarding case and may be related to these girls. he's just about 3 weeks post neuter and is still a bit hormonal so I'm waiting a bit longer before starting intro's. My question: I've swapped out bits of smelly fleece and swapped cages. I let them out to play on the same blanket (but not at the same time) and while the boy is fine with this, I've started having an issue with the girls, they smell the boy and now they've become nippy- they've nipped at my clothing, my hands and one bit my lip, hard but didnt break the skin, another one bit my nipple pretty hard too. I've since washed the blanket they play on and will not be letting them share it any more, to see if that cuts down on this nipping, but my QUESTION is, what does it mean that the girls are nipping me? I am assuming they are riled up by the scent of this male, but what I"m worried about is, that this means they are not going to like him and that intro's will fail. is their behavior an indication of what may happen when I start intro's?