There doesn't appear to be a clear reason behind how they decided to use certain animals and broadcasters for certain reasons.
The full breakdown is:
- In the American, Canadian, French versions, he is a moose. The moose is called Peter Moosebridge which is a reference to Canadian news anchor Peter Mansbridge, who voices him.
- In the Brazilian version, he's a jaguar, voiced by Brazilian journalist Ricardo Boechat.
- In the Japanese version, he's a tanuki, voiced by someone I don't know.
- In the Australian and New Zealand versions, he's a koala named David Koalabell, voiced by Australian entertainer David Campbell.
- In the British version, he's a corgi, (The UK version of Zootropolis, the UK name, is not yet released.)
- In the Chinese version, he's a panda, voiced by someone I don't know.
Looking at each of these animals by location:
- A moose fits the Canadian version. It obviously doesn't fit the French version, but they appear to have lumped them all together in a single release version.
- A jaguar fits the Brazilian version.
- A tanuki is also known as the Japanese racoon dog, so it fits that region.
- A koala fits the Austrlian version, and, like the French with the American verison, doesn't remotely fit New Zealand, but they appear to have been given it anyway.
- A corgi fits the British version, in particular due to Queen Elizabeth II's well known fondness for the animal.
- A panda fits the Chinese version.
So the animals all fit at least one of the regions in which their version of the film is being released. The bigger question is obviously why were these regions put together in this way. It doesn't quite follow DVD regions, or any other pattern I can see, so for now this appears to be unknown. I'd say it's most likely that they were going to personalise a limited amount of regions and France wasn't one of them. Once they'd personalised the rest, which region did France best fit in to? The US/Canada release is probably most likely given Canada's closeness with France.
On a side note, this isn't the first time Disney have done this. Other examples of Disney altering their films for different audiences include:
Inside Out: In Japan, the broccoli Riley despises so much is replaced with green bell peppers, where the food is far more hated by the country's children.
While Riley's dad, a cold weather state American who loves hockey, daydreams about a soccer match in some countries.
Captain America: Winter Soldier: The list of cultural things the Captain says he'll catch up on is different in the US and UK releases.
Cars 2: The Jeff Gordon voiced Race Car Jeff Govette is changed to other real life race car drivers for the areas they were released in.