Dogs should be offered food at a certain time of day, every day on a routine. The food should be put down for no more than 5 minutes and then picked up. Never leave food down permanently.

I put a certain premeasured amount in the bowl , and put it down in front of the dog, pouring a small amount of water over it to help the dog lubricate it but just before I put it down so there is still plenty of crunch to keep teeth clean. I offer it to the dog for a couple minutes. If he is eating, he gets up to 5 minutes. If he ignores the food, it is picked up and no more is offered til the next feeding time (8 hours later for a puppy, a day later for an adult). The dog gets no treats or chews or anything in between, unless you are doing a specific training session like stack training, in which case the session is short and tiny morsels are used sparingly during the training.

The next feeding period, the dog is offered half what they were offered previously with the same rules--picked up if they don't eat right away or at the end of 5 minutes. If they do eat it, then they get a treat placed into the bowl, not hand fed, and praised. If they don't then the amount is cut further in half for the next feeding. Almost all dogs will learn right away unless they have developed bad habits from early on in which case, they might get really thin before they learn they have to eat according to your plan, but they will not starve themselves. I have had a dog go a week that I got when he was 18 months old before he would eat but eventually got him to be a good eater.

Once the dog is eating what you put in his bowl and anxiously awaiting his treat, re-increase the amount you are feeding to double the amount he has eaten until he is up to the amount you want him to eat and gobbling it down.

You should be able to train any dog to eat a full big meal in 5 minutes or less when you offer it. It becomes almost a reflex, which is good, because if they get nervous on the road and decide not to eat, you are in trouble unless your dog has been trained to eat on command. Lots of dogs, especially toy dogs, are poor eaters when they are traveling, and this permits you to overcome that worry when traveling even extensively on shows, when stress and metabolic need are high and you can ill afford a dog to go off his food.