Today when I took my guinea pigs out of their cage I noticed that one of guinea pigs were limping and had his hand held into his body. He usually isn't the most active Pig, but he is usually very happy and likes to play with my other pig. Today he seems sad and won't move unless he is forced (with little nudges). Do you have any idea what could've caused this and should I take him to the vet. Also he is 6 months old now.
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