

What's considered "old" for a pig?
Ghost just celebrated his 4th birthday on August 1st, and according to basically every resource ever he's entering his "golden years" or is at the very least middle aged, but I haven't noticed literally ANY signs of aging whatsoever. In fact, this is the healthiest he's ever been!
He got a nasty URI when he was about 6 months old, then he for the past 2 summers he had cheilitis. The first time, the vet said he got a "chemical burn" from a bell pepper because it was "too spicy" and gave him an antibiotic course that was too short and caused it to come back with a vengeance. Since then, he was successfully treated it with a month long course of Baytril (yes, it took that long to recede plus another week of dosing with no symptoms just to be safe), then when it came up when we moved states, treated him again with no issue and a much shorter course (1 week). He's had various skin issues needing quarterly medicated baths, but thankfully the baths are preventative at this point.
Yet despite all that he's gone through, he is still incredibly healthy. After getting his crappy immune system sorted, he was able to actually be chubby for the first time in his entire life this year and his body is in the best condition it's ever been at 4 years old. He zooms, pops, and is super athletic and energetic. He has no teeth issues, gut issues (even with needing frequent antibiotics) or any other issues other than vitiligo on his paw pads.
If I didn't have his pedigree, you could've told me he was a 2 year old pig and I would believe it. But it begs the question, how old IS old for guinea pigs, and does their ancestry have anything to do with it?
I've owned pedigreed show pigs and pet-mill randombred guinea pigs, and cuy, and it seems like the mill pigs and cuy are always worse off. Cuy makes sense since they were bred to breed fast and grow fast and big, and thus have shorter lifespans, but mill pigs always have weird health issues at young ages which has always been bizarre to me. Excluding satins and pigs with excessive line breeding, pedigree pigs seem to be the healthiest overall weirdly enough. Also guinea pig care quality has increased exponentially in the past decade, so it makes me wonder if guinea pig lifespans are actually longer than the typically quoted 5-8 years? Where did your guys pigs come from, what health issues have they had, and and how long did they live? I'm super curious :)