They say English Bull Mastiff has one of the shortest life spans of the average K-9. The English Bull Mastiff is not even the largest of the K-9 Family! Why do they have such a short life span?
Bull Mastiffs are large, hefty dogs. They are very heavy. If not cared for properly, they tend to be overweight and this may cause many problems to their health. If you dig around the internet, you will find out that English Bull Mastiffs have a list of health issues:
This affects almost 1/4th of the mastiff population. This generally wears down its immunity and usually cannot be completely reversible. As a hip problem would affect a human, the dogs also finds it very hard to move around with hip problems, especially with the fact that they weigh so much (around 120 lbs - 130 lbs).
Much like hip dysplasia, this creates multiple problems on the elbows of dogs, especially on the cartilages. This can start from the puppy-stage of the dog and can worsen over his growth. Secondary processes such as inflammation and osteoarthritis can arise from this damage, which increase the problem and add further problems of their own. Almost 13% of English Mastiffs are diagnosed with this issue.
These problems are diagnosed to almost 3% of the Mastiff population, but can be avoided with proper care.
- General health issues
Like any dogs, they are also prone to a wide range of cancers. With lymphoma and hepatic cancer leading the list. My own dog died of liver cancer when he was only 6 years old (Although, he wasn't a mastiff). Dogs are also prone to gastro-intestinal issues, as the world is their plate. If they eat plastic and anything like that, it causes many issues. Many dogs are prone to Bloat also.
- Weight issues and Overweight
Dogs such as mastiffs and Labradors have a general weight issue. They tend to grow a lot, if not careful. A heavy dog will have many issues such as weak knees and more dangerously - Cholesterol. Cholesterol can cause heart issues and even blocks.
Having said all this, any big dog is prone to most of these problems. So why does The English Bull Mastiff, which is not even the biggest of all Mastiffs, have a shorter life span? The answer to this lies in genetics. English Mastiffs generally have a poor genetic design, when compared to a cross-breed dog. They have lesser immunity and is very prone to hereditary health conditions. So the answer is simple -
They are designed that way.
It's like asking why humans don't live to a 200 with such a complex and advanced genetic structure. The poor genetic structure, with the high probability of genetic disorders and the weight and size, only adds to their misery.