Using animals in experiments to test the effects of extreme stress requires extreme care and caution, and must follow strict ethical standards and laws and regulations. Here are some common steps and precautions: 1. **Ethical approval**: Before conducting any experiment, approval must be obtained from the appropriate ethics committee. Researchers need to prove the necessity of the experiment and that there are no alternative methods. 2. **Choose an appropriate animal model**: Choose the appropriate animal species according to the experimental goals. Commonly used experimental animals include mice, rats, rabbits, etc. 3. **Develop a detailed experimental plan**: Describe each step of the experiment in detail, including how to apply stress, measurement indicators, measures to alleviate animal pain, etc. 4. **Stress application method**: Determine the specific method of applying stress, which can be physical, psychological or environmental stress. This must be done without causing long-term harm to the animal. 5. **Monitoring and recording**: Real-time monitoring of the animal's physiological and behavioral responses, such as heart rate, hormone levels, behavioral changes, etc., to evaluate the effect of stress. 6. **Humane termination criteria**: Set clear criteria for humane termination when the animal shows extreme pain or cannot recover. 7. **Data Analysis**: Collect and analyze data to draw scientific conclusions about the effects of stress. 8. **Sharing and Reviewing Results**: After peer review, publish the results so that the scientific community can review and provide feedback. It is important that researchers always put animal welfare first throughout the experiment, minimize animal pain and anxiety, and always follow the "three R" principles (reduce, replace, optimize).