FEEDING DURING LACTATION

I feed the dam puppy formula kibble. Here is the suggested feeding-during-lactation schedule and the drying up process schedule that I use - it is from the "Dog Owners Home Veterinary Handbook" (DOHVH):
Note: This schedule is for an average size litter. I keep an eye on the milk production and usage and I adjust the daily intake for litters of less than 4 and litters over 6. What you don't want to happen is have her produce more milk than she can use - you'll find yourself having to use a breast pump to reduce the volume of milk. (Been there; done that - but only once! I'm a quick learner)
DOHVH reads, "During lactation a bitch's caloric requirements increase by 25 percent per week."
DOHVH reads, "By the second or third week, a nursing dam eats three times the normal daily (prewhelp) ration - or three full (prewhelp) meals spaced throughout the day." (Note: I feed this ration through weaning - which I start at 4 weeks of age.)
Second Note: Example - three times the normal ration for my girls that normally eat 2 cups of food a day would be eating 6 cups of food during the 2nd and 3rd week of nursing (an average size litter). For a litter of 2 or 3 puppies I would reduce Mom's lactation meals to 4-1/2 to 5 cups a day - amount depends on how much milk she is producing. For a litter of over six I watch the milk production and feed 6-plus cups as needed. Provide Mom with plenty of water - it helps with the production of milk.

DRYING UP PROCEDURE

DOHVH reads, "When the puppies start to eat from a pan, there is less of a demand on the bitch's milk supply. To start the drying-up process, begin to decrease her intake of food. Withhold all food and water the first day; the next day feed one-fourth the normal (prewhelp) amount; the thrid day, one-half, and the fourth day feed three-fourths the normal (prewhelp) amount. Restore normal rations the fifth day.