how old are the pups ? i start feeding puppy food with milk replacer in the form of a soupy consistency to pups at 3 weeks old takes alot of demand off the gyp . and you cant beat rice for bulking a dog up .
x2...also I do it the lazy mans way...

I soak some puppy food with just enough water for it to soften up for the next day...I use enough food for 2 meals.
The next morning I take enough for the first meal and I add a small amount of milk to make it mushy and a little soupy and warm it up in the microwave.
Repeat in the evening but then I make a new batch for the next day and let the soaking over night work for me...Can use calf milk replacer but the the pups don't like it as much as a little cow milk in the food. Besides, a high quality puppy food has all the nutrition needed for a puppy...