Humane end points are required to be seriously considered if tumor experiment on animals to reduce pain, stress and illness of the chosen animals. Euthanasia should be implemented before the following circumstances:
Expectation of death.
Extreme weak physiology conditions.
Tumor burden that lead to ulcer and abnormal behavior.
Currently, there are not yet precise quantitative indexes for upper limit of tumor burden. However, in general, tumor should not exceed 10% weight of the chosen animal.
Ascites should not exceed 20% weight of the chosen animal if ascites tumor, including hybridomas.
Weight loss should not exceed 20% weight of the chosen animal if anti-tumor experiment.
Visual observation is necessary every day for quick responses if anything. Observation items include appearance, gesture, behavior and physiological reactions, feed and water consumptions, weight variations and tumor burden etc.
