What to record
Where it is, its length and width in millimetres, whether it feels soft or firm, whether it moves under the skin, and a photo in the same light each time. Note stiff joints too.
When to call your vet
Any new lump, one that grows quickly, feels firm or fixed, changes colour, bleeds or bothers your dog. Only a vet can tell what a lump is, usually with a quick needle sample.
Our Mufasa had a lump on his front left leg that turned out to be cancerous. Tracking it clearly would have helped us so much.