Prescription drug

Where is Anas Platyrhynchos Feather and Anser Anser Feather and Gallus Gallus Feather made?

2 companies sell it under their own name. None of their labels names the factory.

Companies and their factories

Company on the labelFactoryWhereLast FDA inspection
Allergy Laboratories, Inc. Feather Mix, Chicken/Duck/Goose0.33 g per 20 mL / 0.34 g per 20 mL · NDC 54575-296The label doesn't name the factory. Plants this company names for other drugs
Antigen Laboratories, Inc. Feather Mixture0.0167 g per 1 mL, 0.0333 g per 1 mL · NDC 49288-0207, 49288-0206The label doesn't name the factory. Plants this company names for other drugs