The symptoms before death and how many days an old dog can live are relatively complicated, because each dog's physical condition and life span are different. However, the following are some common signs of old dog death and general life prediction:

1. energy decline: the old dog's activity decreases, and it becomes lazier and more tired.

2. Loss of appetite: Old dogs are no longer interested in food and eat less.

3. Weight loss: The old dog began to lose weight due to the decrease in food intake.

4. Dyspnea: Old dogs may have symptoms of shortness of breath and dyspnea.

5. Persistent pain: Old dogs may have joint pain, incontinence and other symptoms.

It is difficult to predict the estimated time of death, but according to the general situation, the possible life span of an old dog varies from a few days to several months after the above symptoms appear.

It is important to pay attention to the comfort of old dogs and provide warmth and comfort. The best way is to work closely with veterinarians to ensure that old dogs are properly cared for, monitor their condition and seek professional advice if necessary.