AAFCO Ch6 chelated zinc

AAFCO Ch6 definition 57.142 Metal Amino Acid Chelate is the product resulting from the reaction of a metal ion from a soluble metal salt with amino acids, with a mole ratio of one mole of metal to one to three (preferably two) moles of amino acid, forming coordinate covalent bonds. The chelating ligand(s) are a mixture of hydrolyzed amino acids with an average molecular weight of approximately 150, or are specific amino acid(s); the resulting molecular weight of the chelate must not exceed 800, and the minimum metal content must be declared. When used as a commercial feed ingredient it must be declared as the specific metal amino acid chelate — e.g., Zinc Amino Acid Chelate (IFN 6-20-987) (Proposed 1986, Adopted 1988, Amended 2009). Chelated zinc is used as a trace mineral source with the intent of improved bioavailability versus inorganic sources such as zinc oxide (AAFCO 57.117). Note: the AAFCO 2014 dog nutrient profile lists a zinc minimum (100 mg/kg DM growth, 80 mg/kg DM adult) but sets no zinc maximum, so claims of an "AAFCO maximum of 2000 mg/kg" are not supported by the profile table; the definition itself specifies no bioavailability percentages.