Guys, I'd talk to your breeder about how much to feed, and what they've found works well for their dogs. A lot of vets aren't that familiar with giant breeds, and the bags, as far as I've seen suggest feeding WAY too much. There really isn't a right amount. Just watch YOUR dog's weight. You should always be able to feel their ribs and they should have a waist. My 4 mo old pups are gaining about 5 lbs a week, and that's normal. When they hit 12-18 mos, that rapid growth stage ends and you'll actually have to cut back on their food. That's why it's important to check their weight every time you pet or groom them. You can adjust the amount up or down by a small handful if you notice a change. How much you feed your Newf should be determined by that dog's activity level and metabolism. That's why there are no firm rules. Feed the kind of food and amount that meets the needs of YOUR pup.
Lynne