We changed Rio's diet at 2 years. Being he was (is) a very active pup and with us living in AK at the time, his puppy food suited his dietary needs. It wasn't uncommon for us to take 7 miles walks (we called it around the corner) any given day, so the proteins and nutrients he needed to sustain in the cooler climate were higher in his puppy food. Once he settled somewhat and decided he did not like the walk around the block (too many big cats and bears for him) we transitioned him to his adult formula.

One thing that is rarely considered is climate. The colder the climate the more the body tends to burn, requiring one to want to eat more. The same with the storage factor. When it got into the really cold months we cut down his food quantities along with the activity level. Where we were at, it was common to have temperatures in 30 below with the wind chill factor. This is considerably dangerous as it only takes a few minutes for your lungs to freeze if you do not have proper facial cover (which dogs don't).

So if you make a drastic move in climate consider this factor in your pet'd dietary needs.

Remember all pets react differently to changes and no 2 are exactly the same.