I have found that crows like dog food kibble, but not the kind with pointy shapes. Do they prefer the round shape? It's probably more comfortable in their craw. One of my crows came down to eat some dog food this afternoon while I was hanging laundry, not 10 feet away and didn't mind that I looked at it from time to time.
Since I don't have a dog, I have never tried dog food, but it makes sense that they'd like it. Good protein, probably tasty, portable. Probably fine if your dog has its bowl inside, but probably not so nice if the dish is outside (the crows might get the message that it's their food, not the dog's!).
Updated on February 15, 2018