My research said that it can work if you do it right. It is very hard and requires constant monitoring of the dog. I wouldn't recommend it but it will work better than cats. The problem I can forsee is a vegan owner moving there dog to a vegan diet and then refusing to accept that that there dog is having health issues because of it. They would need to be willing to start giving there dog regular food again but I don't see the extreme vegans doing that. They will likely just shove there head in the sand or blame something else like the vet.