Depends Little Hawk, 15 or 20 cats in a single room can smell pretty awful too, especially if the litter box isn't changed often enough.

I've been in rooms where there were over 25 rats and it smelled just fine, you've just got to work a little harder changing the litter. Haven't found any pet yet that cannot be a little odiferous on certain occasions.

Don't know about your dachshund, but ours was noteable for regularly rancid farts, the kind that snuck up silently, when he was sitting in your lap.

At least my daughter's rats don't fart.....that I've noticed.