Hi, I'm no expert either, but from what it says on their website, it looks like if they're 41-61lbs they should get 2.5-3.5 cups/day. However, it says it can vary based on breed, age, activity level, etc. You could titrate to how hungry the pup seems, how they look (overweight, underweight, etc) and how their stools are.
We are thinking of making the switch from BB Large Breed puppy as well though! That's how I found your post! It seems like a lot of people are having trouble with it with the itchy spots and that is our problem as well. He has some random dry, itchy patches. We treated with an antibacterial/antifungal shampoo (GNC brand from petsmart) and saw some improvement, but not much. It really seems to be since we've been feeding BB Large Breed Puppy. We actually started off feeding him BB Wilderness, then left for 1 wk to get married and the breeder watched him, where she fed him Holistic Select puppy (which he had been eating with her prior, only 1 month before). Then we came back and the vet kind of scolded me and said he should be getting puppy food, so I switched him to the BB Large breed puppy.
Anyway, like I said, since then we've been having the itchy, dry spots. Glad to hear the salmon kind is working for you! I am going to make the switch. I also noticed the calcium is not higher either, which is good for our pups. It's 1% calcium and 22% protein. Eventually when he's an adult, I'd like to switch him to BB Wilderness again.
Anyway, good luck and let me know how you're doing with the BB Basics Salmon. My boy is 6 months old, almost 7 months. I need to weigh him though. Hasn't been weighed in awhile but I imagine he's around 65-70lbs.