USDA CATEGORIES OF PAIN Category B Animals involved Examples: Procedures in breeding or housing only. Breeding Colony Only (no genotyping) Housing Only (no procedures) Observation in Natural Habitat (no physical contact with animals) Category C Animals involved Examples: Procedures in experiments, teaching, research, Alert Animals (behavioral observation or surgery, or tests brief restraint) which are Change in Environmental Parameters (light conducted cycle, temperature, etc.) involving no pain Chemical Carcinogens and no distress. Euthanasia Followed by Tissue or Organ There should be no Harvest use for pain- Food or Water Deprivation or Limitation relieving drugs. Forced Exercise Microbiological Agents Non-Surgical Collection of Body Fluid (blood, urine, etc.) Observation Only (while housed in an animal facility Simple Injections (intravenous, subcutaneous, intradermal) Radioisotopes Use of Parasitic Hosts (i.e. to feed ticks) Category D Animals involved Anesthetize and Release ( i.e. for blood Procedures in experiments, sampling) teaching, research, Antibody Production: Monoclonal & surgery, or tests Polyclonal which are Burns conducted Controlled Toxic Substances, Toxic Drugs, involving or Alcohol accompanying pain Electric Shock or distress to the Footpad Injections (antibody productions animals and for or microorganisms) which appropriate Gavage anesthetic, Induction of Illness (including the analgesic, or administration of toxic substances) tranquilizing drugs Lavage are used. Survival Surgery (major or minor – includes multiple) Non-Survival Surgery Transgenic Mouse Production and Maintenance Tumor Induction or Implantation Prolonged or Unusual Restraint Category E Animals involved Death as an Endpoint Procedures in experiments, Lethal Dosage Studies teaching, research, Noxious Stimuli From Which There is No surgery, or tests Escape that involve Pain Studies accompanying pain or distress, and for which the use of appropriate anesthetic, analgesic, or tranquilizing drugs are not used because they would adversely affect the procedures, results, or interpretation of the data.