Causes why cats tremble:

1. Cold. Cats are heat tolerant but not cold tolerant, and are particularly sensitive to changes in temperature. When the temperature drops repeatedly or suddenly, or just after taking a bath, cats will tremble slightly due to the cold.

2. Fear. When a cat is just brought home, or is placed in a strange environment, or sees strangers or animals, it will tremble slightly because of nervousness and fear.

3. Calcium deficiency. Calcium deficiency in cats will cause trembling, loss of appetite, and malnutrition.

4. External parasites. Infection with external parasites causes body itching and trembling, so cats should be dewormed regularly.

5. Sickness. If your cat is trembling and trembling, accompanied by loss of appetite, poor mental state, sneezing, lethargy, etc., then it is likely to be sick.