⠀ A good egg layers feed that's better than my current feed.

[DrPatrickBiggs]

Why does it have to be 16% protien why not higher?

Excellent question!

There is no way to answer this without getting into some technical details, so bear with me here. Protein is made up of amino acids. Think of a chain. The entire chain is protein, and each link in the chain is an amino acid. Animals have a requirement for amino acids, not protein. A diet containing 16% protein typically has the right blend of amino acids needed for proper production of eggs. When you start providing higher levels of protein, you may not be adding the right amino acids and the protein/amino acids may not be as digestible (usable) by the animal. Any excess protein provides a food source for bacteria in the gut that can be bad for the bird’s overall health. Think of it as a prebiotic for bacteria that you don’t want to grow inside the animal. Plus, all of the excess protein ends up being excreted into the bedding and becomes ammonia, which is also not good for your overall bird’s health. Limiting the amount of protein in the animal’s diet is beneficial to the animal’s overall health.