We currently dont know if there is a time difference between catz and dogz. However we are recently had a bunch of runs submitted on different consoles so we can now test which console has the fastest load times.
As far as I know, the only difference between Catz and Dogz is that there are Dogz instead of Catz. Maybe sidequests are different, but from the looks of it, the whole run is exactly the same.
Retouching on version differences.
Only thing that is very obvious is that Sia (the first time) wants an Apple in Dogz and a Cherry in Catz.
Apple is always in the same spot, so it's pretty quick. Cherry is in 1 of 3 spots. If Cherry is in the spot next to the bushes then you save time over the Dogz version. If Cherry is in spot 2 or 3 (Near trees, near where wood for sign is) then you lose time over Dogz version.
Everything else, items required included, is the exact same. Granted, this doesn't count side quests as I have no idea how any of those works.
All in all they're just about equal.
Apple in dogz is not always in the same spot. It's sometimes near the player spawning point.
The jade fields island side mission is another difference between catz and dogz (you have to catch fish in catz, and catch bugs in dogz), but isn't required to beat the game. It could only make a difference if anybody is dedicated enough to do a 100% speedrun.
