Your Puppy's Diet: Accounting for Size

A newborn toy puppy may increase its birth weight by a factor of 10 to 20; a newborn giant-breed puppy may increase its birth weight by a factor of 50 to 100. All puppies grow fastest when they're very young, but the period of rapid growth lasts much longer - up to about 8 months of age or longer - for the largest dogs. Both large and small breed dogs have very different feeding requirements as they grow---and you need to know how to feed your growing puppy so he can grow up healthy.
 
Large breeds: It might seem that you should heap your large-breed puppy's bowl full of calories and calcium---and in fact, breeders did so for years---but we now know that skeletal disorders such as osteochondrosis, panosteitis and hip dysplasia may be adversely influenced by feeding too much of a good thing to these puppies. In the 1970s, nutrition researchers began to suspect that more was not better. The suspects: excess protein, calories, and calcium. 

Protein, traditionally higher in puppy foods, was an early suspect. But research showed protein was not the culprit after all. Protein is important for building muscle, which in turn helps develop sound conformation. Large-breed puppies should eat a puppy food with about 26% protein level to support muscles and tendons. 

Calories are vital for growth and activity; very young puppies require at least twice the calories per pound that an adult dog does, and they have a limited ability to eat a lot. So it's usually safe to feed a calorie-dense food to young puppies. But as they age, they require fewer calories per pound and are able to eat more food in proportion to their weight. It is suspected that puppies that consume too many calories and grow too heavy have a higher risk of osteochondrosis, hip dysplasia and other joint problems. A diet with about 15% fat provides enough calories for growth but not enough for the rapid growth that can encourage skeletal disease. Ultimate size at maturity is genetically programmed; puppies that grow slower will still reach the same size, just a little later---and a lot healthier. 

Calcium is frequently added by owners of large breeds in the belief that it's needed to form strong bones. But while it's true that a calcium-deficient diet can result in weak bones, a calcium-excessive diet can do just as much harm. When too much calcium is absorbed, the body takes it out of the bloodstream by depositing it on bone tissue, whether the bone needs it or not. As this continues, the bone is reshaped in several ways that can lead to skeletal abnormalities. Calcium levels must be adjusted along with calorie level so that a puppy eating the proper number of calories is also eating the proper amount of calcium. This is another reason you can't just give a large-breed puppy less of a regular puppy food or more of an adult diet food. The calcium (as well as the important calcium-phosphorus ratio) will likely be wrong for a growing large breed.

What's a large-breed owner to do? The best bet is to feed a commercial food specially formulated for large-breed puppies. Don't add supplements, especially not calcium, and don't overfeed your puppy.

Toy breeds: Toy breed puppies have their own special needs. Of greatest importance, they are susceptible to a potentially fatal condition known as hypoglycemia. This comes about because very young small dogs have difficulty storing adequate amounts of glucose as glycogen. If they don’t eat often enough, or if they use a lot of energy from playing or being stressed or chilled, their body depletes its stores of glycogen. When that happens, the body starts breaking down body fat for energy. But because small puppies have little body fat, that energy source soon runs out. The body runs out of sufficient energy, and the brain, which is highly dependent on glucose, is one of the first systems to fail. The puppy becomes abnormally sleepy, weak, and uncoordinated, to the point he may not even eat when offered food. If he doesn’t eat, the condition can progress to the point the puppy has seizures, loses consciousness and dies. Toy puppies are especially at risk between 6 and 12 weeks of age, but the threat remains for many up to 7 months, and a few are susceptible even as adults.

To avoid hypoglycemia, feed toy puppies frequently. A young (under 4 months) toy puppy should be fed four to five times a day, and allowed to eat as much as he wants. From about 4 to 7 months of age, he can eat four times a day; from 7 to 9 months of age, three times a day; and by the time he's 12 months of age, twice a day. When the dog can't be fed as often as suggested, he should be kept warm and quiet so he doesn't expend a lot of energy. To avoid a rollercoaster effect with blood sugar levels, be very careful and consistent about what, how much, and when you feed your puppy.

Toy puppies have little teeth, so they do better if fed a small-kibble food. Your best bet is to buy a commercial food specially formulated to meet the needs of small-breed puppies.