The document is designed to aid Dietary Exposure Branch reviewers in their evaluations of livestock pesticide feeding studies submitted by petitioners and registrants. It informs the public and registrants of what factors are considered in the review process. Livestock feeding studies are required under 40 CFR 158.240 when residues of a pesticide requested for registration under the amended Federal Insecticide, Fungicide, and Rodenticide Act appear in livestock feed. Such residues could be due to treatment of agricultural crops or to international addition of the pesticide to the livestock feed (a feed-through). The animal studies are also needed to set tolerances for residues of pesticides in meat, milk, poultry and eggs under Section 408 of the Federal Food, Drug and Cosmetic Act. Exposure of the public to pesticide residues from ingestion of the raw agricultural commodities can then be estimated.