Failure to feed your pet dog for a long time can lead to a series of health problems and behavioral changes. These observations may include： 1. **Weight loss**: Dogs will begin to consume body fat and muscle, resulting in a significant weight loss. 2. **Weakness and fatigue**: Lack of energy sources can make dogs weak, slow to move, and even difficult to stand or walk. 3. **Mental malaise**: Dogs may appear listless, lose interest in their surroundings, and even show symptoms of depression. 4. **Dehydration**: Not eating for a long time may cause dehydration, especially if the dog does not get enough water. Symptoms of dehydration include dry mouth, sunken eyes, and decreased skin elasticity. 5. **Vomiting and diarrhea**: Hunger may cause excessive secretion of gastric acid, causing vomiting. In addition, long-term starvation may cause digestive system disorders and diarrhea. 6. **Hypoglycemia**: Dogs may experience symptoms of hypoglycemia, such as trembling, weakness, or even coma. 7. **Abnormal behavior**: Dogs may become restless, try to find food, or even appear aggressive. Some dogs may start to chew or swallow non-food items, such as furniture, plastics, etc. 8. **Organ damage**: Long-term starvation can cause damage to organ function, especially the liver and kidneys, which may cause serious health problems, such as liver failure or kidney failure. 9. **Decreased immunity**: Malnutrition weakens the dog's immune system and makes it more susceptible to disease. 10. **Death**: In extreme cases, prolonged inactivity can lead to organ failure and death. In order to ensure the health of pets, it is recommended to follow the recommendations of veterinarians and provide pets with the right amount of food and water on time. If your pet has loss of appetite or other health problems, you should consult your veterinarian in time.