Please help because I am stumped. All my training and rescue buddies are stumped and my vet is stumped.
My elderly terrier/hound cross has taken to barking on a night. It's a series of 2-3 barks at intervals until someone goes to sit with him. It's not separation anxiety as at other times he's perfectly happy to be left and the barking doesn't sound distressed or continuous like SA.
Initially we thought he'd maybe forgot he'd been fed due to his dementia and so started leaving kibble out for him (he's raw fed). When this didn't resolve it we thought he might be missing having a friend so we rescued a puppy for him whom he adores and who has made a massive difference to his overall quality of life. He plays again since having the puppy and runs and enjoys his walks much more. It didn't stop the barking however.
We started later walks in the evening which didn't help. We also started to attempt training and mental stimulation on an evening to tire him mentally however he only seems to grasp sit (tried luring, capturing, clicker training, kongs, puzzle games etc as soon as he knows it's training time he sits and stays sitting until he's clicked and treated. I'm guessing this is a symptom of his dementia as he previously loved clicker training and learning new tricks and puzzles)
We have a DAP infuser and spray his bed with DAP. We leave a night light on and play classical music and he has sleeping tablets from the vets for nights he is unsettled. None of this stops the barking.
He won't sleep upstairs as he seems to remember he is not allowed upstairs and spends the entire night trying to get back downstairs.
I'm all out of ideas. Please help.
The barking is the type of bark he does when he wants something. It's three barks followed by a few minutes silence. Our dog cam shows he paces between barking.