Schematic illustration of the algorithm used to determine whether individual sheep and goats require official unique identification as outlined in the NSEP. The requirement for official identification is primarily dependent on the scrapie status of the animal or flock of origin. For animals without movement restrictions, further criteria can be applied to determine whether official identification is required, but the simplest plan is to always apply official identification (ear tag) to an animal that leaves a farm. *Regardless of age, all ewes, rams, does, and bucks that are transported across state lines are required to have an official identification and be accompanied by an interstate certificate of veterinary inspection unless they are being transported directly to a federally approved market or other premises without a change in ownership, in which case they must be accompanied by an owner or hauler statement to that effect. †Includes movement of animals to a terminal feedlot or slaughter-only auction and animals used for personal consumption (ie, home slaughter). ‡Group or lot identification and an owner or hauler statement can be used instead of official individual animal identification for some animal movements. (Adapted from USDA APHIS. Sheep & goat official ID basics flow chart. Available at: www.aphis.usda.gov/animal_health/animal_diseases/scrapie/downloads/sheep-goat-id-flow-chart.pdf. Accessed Feb 12, 2020.)