However, this can vary depending on several factors:
* Genetics: Some lines are predisposed to certain health conditions that can shorten lifespan.
* Lifestyle: Proper diet, exercise, and veterinary care can all contribute to a longer life.
* Environment: Living conditions and exposure to environmental toxins can also affect lifespan.
* Individual variation: Just like humans, dogs have individual differences that can affect their lifespan.
It's important to note that these are just averages. Some German Shepherds may live longer than 13 years, while others may have shorter lifespans due to health problems or other factors.