I am sorry I included a description but it didn’t post for some reason. It doesn’t bother my guinea pig and a part of it fell off so I’m a bit concearned. It’s a tough flappy scab that’s attached to his handIt would be easier if you wrote and described it, rather than just posting a photo with a title. I’m not sure what it is. It looks like a callus or similar but I’m not entirely sure. There’s something I’m thinking of but can’t remember the word. Does it seem to bother him?
It fell off last night. Thank youHi!
It looks like either something caked to the skin or the start of a harmless skin spur. Please try to gently soak the foot and see whether you can VERY gently work it off. If it is a spur, you won't be able to. Please do not try to cut off the spur too close to live skin because that can cripple a guinea pig.
If in doubt, please see a vet.