A. There is a good chance that it is a fatty tumor as Labs tend to get them very often. If it is a fatty tumor, this is usually benign and doesn't require any action. The only thing I would recommend is to switch to a better quality food in order to avoid further growth of these tumors and new ones. (Try low fat grain free dry foods).
In order to check and know for sure what type of lumps these are, take him to the vet which will perform a fine needle aspiration and will confirm or rule out this suspicion.
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