I find the aging mechanic fine and quality affecting how long they live also seems great.
But I feel the actual numbers are a bit over tuned for max age. cows living past their average age of 14years is very rare so I feel 20yo for a max age of a q100 cow would seem more realistic.
I think nothing needs to change about how long in "game time" they living. Just that the age they are reporting as being should be a bit lower.
a minor thing.