Why is our seemingly toilet trained...

[TheDowagerCuntess]

....17 month old dog not having a poo during the day, and instead doing it - inside! - at night?

We changed her food about 6 or 7 weeks ago, but surely if this was going to affect things, it would've done so back then?!

I had to change the time I feed my dog. She did have a poo during the day, but often through the night as well.

I also have to give her a walk last thing at night, ten or fifteen minutes. She does the necessary and is fine through the night. A quick pee isn't any good. She's in a routine now and it's working well.

There is a oro-faecal reflex, that means you get the urge to empty your bowels after eating. It's important she isn't fed too late, and has the opportunity to toilet before bed

She has dinner at 5:30, goes for a long walk about an hour later, and we put her out for 10 minutes just before we go to bed.

She never even does a wee when she walks - fair enough - but I don't understand why she won't go after she comes back, and especially when we put her out before we go to bed. That is hours after her dinner, by that point.

Bed time now, and she has just come in after being put out for 10 mins. Fingers crossed for a dry night.

We have an afternoon walk, then she's fed around 4pm and isn't out again till the bedtime walk. That works for her. She is a dog that needs her routine!

Have you tried actually taking her out at bedtime, rather than putting her out in the garden?