At what age to guinea pigs reach their adult weight?
At what age to they quit growing length wise?
I believe after 1 year, their growth will be at a much slower rate.
I was told years ago that a pig reaches their almost adult size at 10 months of age. They are adults at 14 months and have reached their adult posture by then (meaning: between 10-14 months, the bum gets sizier, lol, the facial hair gets fully grown, etc).
Yet, this doesn't apply for a Rex: they develop their full body posture between 10-24 months.
My two haven't grown any since about 10-11 months. They hit their adult weight (about 1250-1350 grams) then, and have been stable in weight and size since then.