Should their back ends look like this after castration?

[AintNobodyHereButUsChickens]

Just picked my kittens up from the vets and both of them look like this and stink of pee, I'm not 100% sure if it's actually pee or just a chemical that smells like it

Streaming the photo would help

I don't remember a pee smell when we had our cat neutered a few months ago.

The area was swollen though and the vet said they get lots of queries asking if the castration had actually taken place.

It could be that they were scared/anxious and urinated in the carrier home - one of mine does that and needs a bath every time, bless him.