October 24, 2018
It’s sad but true: New research led by the University of Sydney has revealed that the life expectancy of chocolate Labradors is significantly shorter than that of their black and yellow counterparts.
The study of more than 33,000 United Kingdom-based Labrador retrievers of all colors—published on October 22 in the journal, Canine Genetics and Epidemiology— found that the median lifespan of non-chocolate Labradors is 12.1 years— more than 10% longer than those with chocolate coats.
The research initiative, led by Professor of Animal Behavior and Animal Welfare Science Paul D. McGreevy at the University’s Sydney School of Veterinary Medicine, “aimed to describe demography, mortality and commonly recorded diseases in Labrador retrievers under UK veterinary care.”
In addition to the findings related to life expectancy, the study determined that chocolate Labradors have a higher incidence of ear infections and skin disease. Specifically, the prevalence of ear inflammation (otitis externa) was twice as high in chocolate Labradors, who also were four times more likely to have suffered from pyo-traumatic dermatitis (also known as hot-spot).
In comparison, across the entire Labrador population, the most common health conditions found were obesity, ear infections, and joint conditions.
Part of the university’s VetCompass Program, which collects and analyzes electronic patient data on dogs; the research now is being replicated in Australia, where Labradors are the most popular breed of dog.
According to lauthor McGreevy said the relationship between coat color and disease came as a surprise to researchers. The UK findings may not hold in Australian Labradors, he said, but warrant investigation.
“The relationships between coat color and disease may reflect an inadvertent consequence of breeding certain pigmentations,” he said. “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.”
“We found that 8.8% of UK Labradors are overweight or obese, one of the highest percentages among dog breeds in the VetCompass™ database,” Professor McGreevy revealed.
The prevalence was higher among male dogs who had been neutered.
Labrador retrievers under primary veterinary care in the UK was co-authored with colleagues from the London’s Royal Veterinary College (RVC), where VetCompass began in 2007, as a collaboration with the University of Sydney. VetCompass Australia now operates as a consortium comprising all of Australia’s veterinary schools, supported by the Australian Research Council.
Research contact: firstname.lastname@example.org