Rats Sneezing/Unexplained Death

One of my small rats which I bought to raise as a breeder has just passed away today. The bunch of them were sneezing for a while but I thought it may have been the new environment + me letting the cage get a little too dirty. Since then I've been cleaning regularly and it seems like on some days the sneezing is better whereas others it's worse. None of them exhibit any other symptoms, no coughing, wheezing, or discharge. Today I discovered that one of the rats looked really skinny, and her breathing wasn't clear. I picked her out and she actually passed away as I was examining her. Does this sound like a bacterial infection?

I haven't lost any other rats yet, though I did lose 2 mice the day that I bought them. I placed them into their habitat and the next day I found two of them buried by the other mice. There were no bite marks or anything and these two individuals did not look skinny or sick at all. A similar case to the rat happened with another mouse from the same enclosure. I noticed how skinny she was and thought her mates were bullying her so I took her out to feed her. After nibbling on some greens she ended up passing away within the hour as well. I don't hear the mice sneezing at all.

Does anyone have some insight on what could be happening and how to cure it? I have doxycycline and tetracycline on hand (aquarium grade) and have ordered some amoxicillin as well.

It could be anything....something in your environment, some illness they had when you got them, or just bad genetics/weak immune systems.

If it is your environment, you are going to have to figure out what it is and fix the issue. Otherwise, you are probably best off finding a place you can get some healthier breeding stock to start your breeding colonies.

if it's a respiratory infection, you can get some tetracycline from a feed store (I get it from Tractor Supply Co). Put about a teaspoon (to a teaspoon and a half) in an 8oz water bottle and change it daily. That usually wipes out respiratory infections. What kind of bedding do you use? Some are more sensitive to pine bedding. I usually use pine shavings from TSC but one of my males is sensitive to it so he stays on Aspen.

It's some type of wood shaving from a local pet store, they sell it in Winco Bags. I do think it might be the shavings so I've ordered tons of aspen. It's taking forever to get here though :/ Haven't had any trouble with the other rats yet so I'm hoping it wasn't anything contagious!

Just as a follow up. The rats started sneezing, wheezing and coughing after a week or so. I ended up treating their water bottle with aquarium-grade doxycycline (literally an upgraded version of tetracycline), and all the symptoms seem to have gone away and no more deaths.

Thanks for the input : )