Put a little pork in there!
The pet food industry as we know it today did not begin until the late 1930's. During this time, two brothers in Chicago thought it would be a good business idea to go around selling canned horse meat (extras people didn't want) door to door. There where no petcos or shoprights to grab a bag of baked kibble or can of water mixed with flour and ground up cow utters displaying fresh salmon on the label.
Most dogs ate and lived off table scraps which were of substantially greater volume and nutrition. This idea went from a few families buying canned horse meat to today's conglomerate 5 billion dollar pet food industry. Today over 150 companies sell over 1500 brands of food.
This volume exceeds human cereal and instant breakfast sales combined. And is of the same or less nutritional value as giving your child a toasted pancake for every meal. Most commercial dog foods will cover a dogs basic caloric needs, but do not be scared to supplement his food with things that are good for you. (Beef, oils, liver, cooked pork, fish, eggs and much more) It will only add to the building of his body and the strength in his years.
-Mangia!