As our pets get older, they often suffer from common senior pet diseases that eventually lead to death. The most frequent causes of death in both dogs and cats are cancer and kidney disease. In addition, 80-90% of senior dogs and cats suffer from arthritis.
Symptoms your senior dog may be very ill include disorientation, preferring to be left alone, avoiding activity, dull coat, loss of housetraining habits, wandering at night, and poor appetite. These symptoms could also be indicators of heart disease, kidney disease, or liver disease.
The most frequent causes of dog death and pet disease among old dogs are cancer, cardiac failure, and renal (kidney) failure. In younger dogs, bloat, and immune-mediated diseases are significant.
The most common causes of cat death in senior cats are kidney failure, cancer, and infectious disease such as FIV (feline immunodeficiency virus). Cats also suffer from hyperthyroidism, which causes high blood pressure, inflammatory bowel disease, diabetes, arthritis, and dental disease.
Cats are less inclined to develop cancer than dogs, but cats with cancer tend to have malignant disease, whereas in dogs, it may be benign. For example, 60% of dogs with skin masses will have benign disease that will not grow aggressively or spread to other locations; but only 20% of cats with skin masses will have benign disease.