Millie has I guess always been a dog who goes off her food.
It started with her being given Royal Canine kibble from the breeder, she ate it a bit, but gradually she was eating less and less and seeming uninterested in it. We then tried switching to Hills Science Plan which the vet gave us, she liked it for a week and then the same again. We switched to Arden Grange and again like it for a week or so and went off ot it. It was pitiful watching her struggle to eat yet not enjoy it.
Then at 5 months after hubby said he too was concerned about her lack of eating, I read up on here about raw feeding and the Barf diet. After reading all I could on it I decided to give it a try. I went for Natural Instinct as it is fully balanced and no prep to do.
From day one she loved it straight away, eating two meals a day. Since Christmas however, she has turned her nose up at it, probably because everyone was sneaking her delicious Christmas ham, turkey, beef the lot
I have come to the conclusion that if she's not hungry she just wont bother eating. On average out of 14 meals a weeks (2 per day) she will refuse 4 of them. Sometimes I serve the food as it comes, other times I may add a little extra of our left over food, ie chicken. I've also swapped to NI's Country Banquet food as well as their standard food just so she has lots of variety.
I just think some cockapoo's are a bit more fussy eaters and don't overeat just because they can.