Tumours are fairly common in an elderly mouse. They can grow very quickly because mice have a fast metabolic rate. Mammary and intestinal tumours are the most common and are the most likely to be cancerous.
When you handle your mouse – and you should do this regularly – check for unusual lumps and bumps on their body and abdomen. If you’re at all concerned, take your mouse to the vet.
When your mouse reaches around 12 to 18 months old you’ll start to notice a few changes, which are very common in mice. These include:
- Hair loss, leaving sparse bald patches
- Sleeping more
- Drinking more
- Lumps and bumps
- Weight loss, but teeth remain in good condition
- Becoming wobbly when walking about. Always keep an eye on your mouse if they’re housed in a mesh cage. Elderly mice can get caught in the bars if their nails have grown.
If you feel your mice are starting to struggle with one or more of these symptoms, talk to your vet. While they’re perfectly natural, you’ll want to make sure they’re comfortable and not in pain.