Cats generally do not suffer from depression. Common symptoms of depression are as follows:

　1. Loss of interest and no pleasant feeling;

　2. Loss of energy or feeling of fatigue;

3. Psychomotor retardation or agitation; ​​​​​​

4. Low self-esteem, self-blame, or feeling guilty;

5. Difficulty in association or decreased ability to consciously think;

6. Repeated thoughts of death or committing suicide or self-harm;

7. Sleep disorders, such as insomnia, early awakening, or excessive sleep;

8. Decreased appetite or significant weight loss;

9. Loss of sexual desire.

Diagnosis can be made by the presence of 4 of the above 9 symptoms.