For Labrador retrievers, color appears to play a role in how long they can be expected to live.
According to a study published Sunday in the journal Canine Genetics and Epidemiology, chocolate Labs have lifespans 1.3 years shorter than labs of other colors.
The study looked at data for 2,000 dogs living in the United Kingdom in 2013 that were randomly selected from the records of more than 33,000 Labrador retrievers in the database of VetCompass, a research project of the University of Sydney and the Royal Veterinary College at the University of London.
The median lifespan for all Labrador retrievers was 12 years. But the average lifespan for chocolate Labs was 10.7 years, the study found. In addition, chocolate Labs showed a higher rate of skin and ear infections.
Researchers said they found the link between color and other issues surprising.
“The relationships between coat color and disease may reflect an inadvertent consequence of breeding certain pigmentations,” professor Paul McGreevy, lead author of the study and chairman of VetCompass, said in a statement. “Because chocolate color is recessive in dogs, the gene for this color must be present in both parents for their puppies to be chocolate. Breeders targeting this color may, therefore, be more likely to breed only Labradors carrying the chocolate coat gene. It may be that the resulting reduced gene pool includes a higher proportion of genes conducive to ear and skin conditions.”