Good protein supplement?

[Mhays]

Have been working on this - cheese gave the birds some loose stools (fine, but more mess than usual) due to the fat. Found whey protein isolate that hits all the required amino acids and added that to the food - but finally, landed on Japanese Katsuaobushi. It's dried, fermented, flaked bonito fish - almost 100% protein plus probiotics. Available anywhere you can get Miso soup, as it's an ingredient in the broth.