Nope, of her estimated adult weight.
Actually once she's through the majority of her growth (1.5yrs give or take) her food intake might very well reduce below that, many folks with giant breeds report it.
In the mean time though, if you're in the US, I'll get you a list of raw feeding co-ops, they're groups of people in a region who feed raw and they do bulk purchases together to help reduce the costs. It can be a very dramatic price savings. You'll need a seperate freezer though (if you don't already have one) cause it does require bulk purchases.
Also, check with any farms or 4H clubs, or the like in your region. Some farms will sell scrap for dog food if you negotiate with them, and some slaughter houses/meat processors will do the same.
Once you're sure she's back to normal you can start adding green tripe. Warning, it smells NASTY, but dogs love it and it'll help with digestion.
No additional supplements needed as long as you're getting the organs in properly. Having said that, I add fish oil a couple times a week cause my two won't eat fish, and right now they're getting treats of extra eggs and a biotin supplement cause one of mine has had a screwy shed/coat grow in this year. And many raw feeders will add coconut oil but that varies with the dog.