Simply by looking at the impressive Neapolitan Mastiff, you can tell that he eats a lot. It is very important that he has a well-balanced, high-quality diet of dry food. Dry food is best because wet food can cause tooth decay, gum infection and bath breath in dogs. Because of the Neo’s size, he should be fed twice daily or free fed to avoid gastric torsion, more commonly known asbloat.
If you get a Neapolitan Mastiff puppy from a breeder, they would give you a feeding schedule and it's important to stick to the same routine, feeding the same puppy food to avoid any tummy upsets. You can change a puppy's diet, but this needs to be done very gradually always making sure they don't develop any digestive upsets and if they do, it's best to put them back on their original diet and to discuss things with the vet before attempting to change it again.
Older dogs are not known to be fussy or finicky eaters, but this does not mean you can feed them a lower quality diet. It's best to feed a mature dog twice a day, once in the morning and then again in the evening, making sure it's good quality food that meets all their nutritional requirements. These dogs need to be fed a diet that contains about 24% protein.
Experienced Neapolitan Mastiff breeders recommend food that is slightly higher in fat and lower in protein, especially when the dog is young, as they grow so fast. Do not supplement with calcium. Check with your vet if you have any concerns about your dog’s weight or diet.Clean, fresh water should be available at all times.