Upon arrival of your puppy we recommend having some soft canned puppy feed on hand and mix it with a good quality puppy feed. Let them eat their fill around three times a day. If they don't eat that maybe try some puppy milk replacer. As far as the type of feed, we use Diamond brand made local near us. It includes probiotics in the feed which we highly recommend.
Also its very important to making sure your dog feed is always fresh. Dog feed is basically preserved meat and if a bag of puppy or dog feed is left setting out in the sun or in a very hot building why it can get toxic with Salmonella and it will kill a dog in a days time. The one very hot summer we where getting our dog feed from a local out in the country dog feed dealer and we had a couple very healthy dogs die very quickly for us and we discovered the feed was poisoned with Salmonella due to the feed mill not storing it properly. We recommend always buying your feed from a location that is properly set up and after unloading the feed that it gets inside quickly and don't leave it sitting out in the hot sun for half a day before they take it inside and also make sure that they store it where its air-conditioned. Toxic feed can kill your pet overnight! We buy feed manufactured near us so its spent less time in a hot trailer during delivery from the manufacturing plant to the store. During the winter isn't as much of a concern as in the summer.