These are recommendations for a gestation/lactation diet. Ideally, the diet should be started when the bitch comes into heat. Many brands actually fit the requirements, most are "performance" or "active dog" foods. Initially the bitch will need to be fed slightly less of the performance food because it will contain more calories per cup than most maintenance diets. The diet is continued throughout pregnancy and lactation. Puppies should be weaned onto puppy foods, not the performance food.

Protein greater than or equal to 28% from animal based sources.
Fat greater than or equal to 18%.
Carbohydrate greater than or equal to 22%.
Calcium: Phosphorus ration of 1.2:1 to 1:1.
Omega 6:3 fatty acid ration5:1 to 10:1

Some diets that meet or come close to the recommendations are Eukanuba Performance, Nutro Hi-Energy, Pro Plan Performance, Healthwise Active Adult, Eagle Pack Power, Natural Life Condition and Bil-Jac Select. Many other diets are available that meet the guidelines and many are available that are used successfully that do not meet the recommendations. If you have a proven track record of success with your current program, there may be little benefit in changing what you feed.