Rats do better with colder temperatures than they do with warmer temperatures, but if it's gets too cold it can be hazardous. Usually rats are okay to ~50 degrees Fahrenheit. Even then they're alright with enough soft bedding and friends to cuddle with.
However, if it gets very cold, and you have no power, there are a few things you can do to help keep them warm.
Pocket Warmers
Pocket warmers are great little things, and can get very hot. If they aren't ones that get super hot, you can put them directly under your rats cage. However, if they are extremely hot, you need to wrap it up in a towel before you put it under the cage, as it may burn your rats.
Blankets
You can also wrap a space blanket around your rats cage to help keep in heat. I think this is the best thing to do, as rats can keep warm if you provide enough bedding for them to hide in.
Other
Every morning, since it's so chilly here and cold in the room when we wake up, I like to give them a nice warm porridge.
- Bob's Red Mill 5 or 7 Grain Cereal (5 grain is more flaky, while 7 grain is more of a soup-y consistency)
- Fruit or vegetable baby food
- a little bit of baby cereal
- water
You just warm up some water, put in the grains, and add baby food. If it's too thin, I'll add a little baby cereal, just to thicken it up a bit. I also like to add some ground flax seed. My rats are a little picky about flax seeds, so I get the Trader Joe's Ground Flaxseed with Blueberry, for flavor and to get them to eat it.
