I have spayed and neutered guinea pigs and not found them to be at any greater risk for anesthetic or surgical death than other companion animals. I use the same anesthesia protocol as I do for rabbits. However, the organization I currently work for chooses not to S/N guinea pigs prior to adoption for a few reasons...which I am happy to further elaborate on if you're interested :-)
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Rachel Powell DVM
Director of Surgery
Greenhill Humane Society
Eugene, OR
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