Talk to your breeder and feed what they were feeding. If you change to something else, you may want to gradually transition to your new brand, mixing some of the breeder’s brand with your brand starting out with mostly the bredder’s and changing the ratio over time until it is all yours.
We fed Pro Plan for years and the Pet Food store told us it was being replaced with something else that had more “good” stuff for the dog so we tried it and it made the dog sick and she was dropping hair in clumps. It turns out Pro Plan was not being replaced so I picked some up and we were back to normal, just $40.00 poorer.