Puppies, unlike older dogs, have no fat stores. Therefore, they cannot go more than 12 hours without eating. This is particularly true for toy breeds that are prone to hypoglycemia (low blood sugar), which can lead to serious complications. Most healthy dogs can go up to five days without eating, although that figure is only true if your pet is still drinking a lot of water.
Some may even go up to seven days without doing so, although you should never let things go that far without taking your dog to the vet. We'll also review the most common causes of appetite loss in young puppies and emphasize the importance of seeing the vet as soon as your puppy stops eating. When it comes to nutritional needs, newborn puppies are quite simple: they get everything they need from breast milk and spend more than 90% of their waking time breastfeeding. If left unfed for more than 7 hours, newborn puppies can get sick with symptoms including a weaker pulse, lack of energy, chills, and fainting.
Newborn puppies and puppies less than three weeks of age can go from two to a maximum of three hours without eating. When puppies turn 4 weeks old, they become stronger and are able to survive longer without eating. Puppies can go several hours without food or water, but the exact number of hours depends on several factors, such as the dog's age, size, and breed. A good rule of thumb is that puppies can generally hold their urine for their age in months plus one, converted to hours.