You shouldn't worm or flea dip/powder/shampoo them until 8 wks or older. Mom should make plenty of milk, but if the puppies aren't thriving, sometimes vit B or oxytocin ( or was it pitocin our vet used) can be given to help lactation. If U DO have to supplement, there's the KMR milk replacer that's available in cans (already mixed) or pwder (mix with water) but you must follow label directions as to life after opening/refrigeration.