Moms will clean up after the pups poop until the pups are weaned and on puppy food. When my pups were getting fat and sassy , I'd wait until Mom started regurgitating her supper which showed she was ready to wean. At that point, I wouldn't let the pups eat that and would start their baby food. This was usually between 5 and 6 weeks. When breeding, I felt nature knew the best..... besides, that saved me cleaning up 30 poops a day ! I feel too many people start them too early on food. They need Mom's milk and as long as they gain and are healthy why rush .