The Rottie pup probably has had urine, saliva, etc. from her littermates at the breeder.
Well, yes, I think that could be. She'll probably smell better in a couple of days. To be fair: When I got baby Luna, she became smellier with each passing day; she was simply too young to clean herself. Had to give her a bath after a week or so, but after that, she was able to bath herself.

But generally, I can stand feline smell better than the canine version of it. Guess that labels me a cat person.

Kirsten