A recent study published in The Royal Society suggests that the likelihood of dogs developing cancer may be influenced by their breed, with larger dog breeds being more prone to the disease. The research, conducted by biologist Leonard Nunney at the University of California, Riverside, analyzed data from both humans and dogs to explore the connection between breed, size, and cancer risk.

According to the American Veterinary Medical Association, nearly half of elderly dogs over the age of 10 will develop cancer. However, the study found that larger dog breeds, except for the largest ones, actually have a reduced risk of developing cancer compared to medium-sized canines. This contrasts with previous studies showing that taller individuals in humans have a higher overall risk of cancer, potentially due to increased organ size and faster organ growth.

Out of the 85 dog breeds studied, the research identified that flat-coated retrievers faced a significantly higher risk of dying from cancer. Additionally, Scottish terriers, Bernese mountain dogs, and bullmastiffs exhibited a notable risk, more than 50% higher than expected. These findings shed light on potential genetic factors that contribute to cancer susceptibility in certain breeds.

The study also investigated the impact of inbreeding and genetic diversity on cancer risk. Inbreeding, which reduces genetic diversity, can increase the likelihood of specific cancers in dog breeds with low genetic diversity. For instance, flat-coated retrievers were found to be particularly susceptible to sarcoma, a rare form of cancer that affects bones and soft tissues, while terriers were more likely to develop bladder cancer.

The researchers utilized a two-step approach to conduct the study. They first analyzed data on cancer-related deaths among dogs of different breeds and then examined factors such as inbreeding levels to assess their relationship with cancer risk. According to Nunney, this model can also serve as a useful tool to identify potential increases in specific types of cancer within breeds in the future.

Understanding the potential links between breed, size, and cancer risk in dogs can help veterinarians and dog owners be more vigilant in monitoring and managing their pets' health. Further research in this area could provide valuable insights into the prevention and treatment of cancer in dogs, potentially improving the overall well-being and lifespan of our furry companions.