FDA CFR21 part501 labeling

21 CFR Part 501 (revised 2024 modernization) sets FDA's labeling standards for pet food. Required Principal Display Panel elements: (1) statement of identity (product name with species designation); (2) net quantity statement in dual units (oz + g, lbs + kg); (3) name and place of business of manufacturer/packer/distributor. Required information panel elements: (1) ingredients list in descending order by weight (as fed basis); (2) guaranteed analysis: crude protein min%, crude fat min%, crude fiber max%, moisture max%, ash max% (if claimed); (3) nutritional adequacy statement (AAFCO protocol); (4) feeding directions (with daily caloric content for the recommended portion); (5) best before date + lot number. The 2024 modernization added: (a) mandatory 'human grade' claim must meet 21 CFR 110 human food cGMP for entire production chain; (b) functional claims require 'competent and reliable scientific evidence' substantiation.