Interesting reading, CS.
The farm house my wife was born in, in Abruzzo, had the animals stabled in winter on the ground floor.
The arrangement meant the heat of the animals, arising, helped keep the human inhabitants on the next floor warmer.
I did, once, ask about the smell but the question received a look that meant “drop it….or else”. I am, of course, a city boy & not always appreciative of the agricultural way of life.
That same arrangement was common in the UK until quite recently too. In a single storied building, the livestock would get one end, there would be a central passage way and the family would be up the other end. https://en.wikipedia.org/wiki/Dartmoor_longhouse (I hadn’t realised that the design wasn’t common in other parts of the UK)
I’ve stayed in houses with the same arrangement that you describe, in Nepal. TBH you wouldn’t even notice the smell after a few days.