Humane endpoint refers to the point at which an experimental animal's pain and/or distress is terminated, minimized or decreased. It includes actions such as humane killing, terminating a painful procedure and giving treatment to relieve pain and/or distress. Using humane endpoints in animal protocols is a refinement and provides an alternative to using death or severe signs of animal pain and distress. They are essential in those situations with a strong potential for pain and distress (e.g., acute toxicology, or animal models of infection, cancer or inflammatory disease). However, a humane endpoint in a scientific study also ensures that the scientific goal of the study is reached.
Humane endpoints are established before the start of a study.
Selecting a Humane Endpoint
A moribund animal is one that is close to death and may be unresponsive, for example, to stimuli, exhibit dyspnea (breathlessness), hypothermia, prostration. However, once the point of being moribund is reached, detailed observations can help to set an earlier experimental endpoint.
Steps to develop humane endpoints include:
Humane Endpoint Score Sheets
Using observational checklists or score sheets for scoring an animal's condition in a study provides an objective basis for decisions about endpoints. Score sheets help ensure that specific observations are not overlooked and help improve observational skills, particularly with the smaller laboratory animals. However, score sheets do not cover all abnormalities or observations, and cannot replace a thorough examination of the animal.
This section has been adapted from the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) website and CCAC guidelines.
For more information on humane endpoints, the following resources may be useful.