Guideline #1

Humane Intervention Points

1. References: The Guide for the Care and use of Laboratory Animals: Eighth Edition. Nation Research Council. Chapter 2, pp.27-28 and Chapter 4, pg.114.
2. Purpose/Scope: These guidelines are intended to provide clinical (physiological or behavioral) criteria to assist personnel to recognize humane intervention points to minimize pain and distress, and to prevent death as an endpoint. Knowing these sometimes-subtle clinical manifestations can aid animal care personnel and researchers relieve unnecessary pain or distress by providing optimum care. The Animal Monitoring Plan within the approved ACUP must define parameters, monitoring criteria and appropriate interventions that will be implemented during the experiment.
3. When establishing an Animal Monitoring Plan, humane interventions parameters should:
   • Be appropriate for the study.
   • Be objective and measurable, when possible.
   • Have monitoring frequency, humane intervention points, and interventions clearly defined.
4. Humane Interventions may include but are not limited to:
   • Consult clinical veterinarian to determine proper treatment
   • Provide approved treatment to alleviate pain or distress such analgesia and/or supportive therapy (dietary supplementation, fluid therapy, etc.)
   • Discontinue experimental procedures until animal recovers
   • Remove animal from the study
   • Increase the frequency of observation to ensure early detection of unnecessary pain or distress
   • Euthanize the animal
5. Commonly used Animal Monitoring Parameters monitored for Humane Intervention Points may include but are not limited to: (should be appropriate for the species and expected clinical signs)

• • Breathing rate
    • very slow, shallow, and labored
    • rapid
  • Weight loss
    • ≥20% compared to weight at the start of the experiment for acute/short-term studies
    • ≥20% compared to control animals or animals of similar age for chronic/long-term studies
  • Body Condition Score (BCS)
    • For mice, a BCS ≤2 on the Ullman-Cullere et al. scale
    • For rats, a BCS ≤2 on the Hickman and Swan scale
    • For other species, the BCS should be defined and referenced
  • Ambulation
    • Impaired ability to rise or move around the cage/pen
    • Impaired ability to reach food and water easily
    • Observed lameness
  • General Appearance
    • Ruffled fur (rough hair coat)
    • Hunched posture
    • porphyrin staining
    • urine or fecal staining
    • squinting and/or tearing
    • lethargy
    • hiding and/or not interacting with cage/pen mates
  • Temperature
    • should be quantitatively monitored when appropriate for the monitored species
    • in smaller species changes in body temperature can often be detected by just touching the animal
    • Hypothermia or hyperthermia based on acceptable reference range per species
  • Ulcerative dermatitis or self-induced trauma that creates wounds
  • Inappetence (lack of appetite)
  • Diarrhea or constipation
  • Neurological signs that impair the ability to eat, drink and ambulate
  • Bleeding that cannot be stopped
  • Dehydration
  • Post-surgical complications
    • Dehiscence or infection of surgical site
    • Uncontrolled bleeding
  • Tumors
    • See guideline #18 Tumor Burdens in Animals

6. Signs for Judging the Moribund Condition (state of dying) in Rodents

• • Signs for morbidity plus:
    • Impaired ambulation (often resulting in the inability to reach food or water easily)
    • Evidence of muscle atrophy or other signs of emaciation (body weight is not always proportionate)
    • Any obvious prolonged illness including such signs as lethargy (drowsiness, aversion to activity, lack of physical or mental alertness), prolonged inappetence, bleeding, difficulty breathing, central nervous system disturbances, or chronic diarrhea or constipation
    • Inability to remain upright

7. Death as Endpoint

• • It is almost never acceptable to allow a study to continue until an animal dies. Strong scientific justification must be approved by IACUC for such a study.
  • Unexpected deaths and unexpected outcomes or adverse events must be reported to the AV and IACUC in accordance with Guideline #23 Mandatory Reporting to the AV and IACUC.
  • Federal guidelines authorizes veterinary staff to euthanize animals in states of unauthorized, uncontrolled pain or distress. The PI is strongly encouraged to work closely with CMG veterinary staff in cases where this situation may exist.

 

LAST REVIEWED AND ADOPTED BY THE IACUC: February 6, 2025