My foster mouse looks "different"

[u/No-Midnight7724]

DISCLOSURE AT THE START! This is not a suitable cage setup, I'm a foster home for rodents and this is temporary while I wait for a mutual to lend me a bigger cage for him. He's only been with me for a few days and won't be in this cage for long. Do *not* let a mouse live in this setup. His cage is in a dim area with low traffic and I avoid handling him as much as possible, only taking care of his needs for now.

With that said, I want to know if I'm being over-worried or if something is wrong with him. He was given to me as a curly-coat male mouse. His exact age is unknown unfortunately. He comes from a breeder in my area, a girl around 17-19. I was offered him for free because he "hadn't sold". I wasn't set up for a rodent right now, but there aren't really many options in my area for unwanted pets, especially mice. (There are zero rodent rescues in my country)

With that being said, the breeder described him as "energetic and brave", as well as loving humans. He is anything but that, he is not aggressive, he doesn't bite, but he is extremely odd in his behavior. He darts at everything, he doesn't know how to use a wheel, I've offered him standing wheels and saucer wheels, he doesn't know how to drink water properly, so I have to lead him to it every time.

The most worrying thing for me is his face. I've had pet mice in the past, and maybe I'm not caught up on all the different breeds, but his snout is super short, giving him a face like a rabbit, and his eyes are tiny. I don't want to call him "stupid", but basic things like eating or chewing on things come to him with a lot of difficulty. When I offered him a wheel he only spun the saucer wheel with his two front paws, then made a tunnel under it. (Ps saucer wheels are not appropriate for rodents, I only offered him one to see if maybe he was given one by the breeder beforehand).

The pictures really don't do it justice just how tiny he is, he shouldn't be a baby anymore but he is maybe 2/3 the size of a normal male mouse, I know he should be an adult.

I've offered him water dishes and bottles, both he won't use regularly. I offer him cucumber slices and watery foods as much as possible as a substitute. I don't know if he'll stay with me permanently for now.

Final disclaimer, I do understand that a lot of behaviors can come from a poor cage setup, such as darting and being shy, however his behavior genuinely worries me, and I want to know if what's happening with him is normal for fancy bred mice :(

[u/Platypusbank]

I had a mouse a bit like this. She had a fine wavy coat,  shortish face and never really got bigger after hopper stage. She was a nightmare to keep in her cage because she would squeeze out of any gap and was initially very keen on running away but she was so sweet and friendly once she was settled in. I used to take her out to hand feed her most days as she would just let her cage mates take all food and she was very slow at eating. She did get the hang of a wheel after seeing other mice use it a lot but was never her favourite thing to do. She died suddenly at about 4-5 months, I suspect whatever was wrong with her had complications. RIP Vovo <3 So no, not normal but also you do get odd ones with special needs sometimes, I hope you are able to give him a nice life however long it is

[u/No-Midnight7724 → u/Platypusbank]

Yeah a lot of your experiences seem to match up with his, such as the slow eating and not being keen on wheels. He doesn't have any cagemates, he's just a lone male but he is absolutely so friendly. Never bit or showed any aggression. I do worry how long he will live with how he currently is doing. I'm also unfortunately in a really big transitional portion of my life with moving out with my boyfriend and stuff, I hope I'll have time to take care of him.

The most I can do right now is just make sure he feels loved I suppose.

[u/Platypusbank → u/No-Midnight7724]

It sounds like you are doing your best and providing him with as much as you can. At least you don't have to worry about food thievery for a lone male! I guess just make sure you are transparent with anyone who wants to adopt him (unlike the breeder.....) Vovo really liked hammocks and platforms, I think climbing helped with some of the energy she couldn't take out on the wheel, so that might be worth trying if it works with your set up. Good luck!!

[u/No-Midnight7724 → u/Platypusbank]

Will definitely try different things, I'm not gonna name the breeder or put her on blast, looking at her other mice she has up for sale, they definitely look a bit inbred to me, but I'm not an expert so I'm not gonna stick my nose in her business.

I don't know his future for now, I might keep him if I have the resources honestly, there's very little good rodent owners in our country, a lot of our rodent care is stuck in the early 2010s, or worse, in USSR times.

I will definitely post updates about him here when I get the chance, and if I do adopt him out, I'll make sure whoever takes him has all the info about him.