Longevity and mortality in Kennel Club registered dog breeds in the UK in 2014

Abstract

Background: The domestic dog is one of the most diverse mammalian species, exhibiting wide variations in morphology, behaviour and morbidity across breeds. Therefore, it is not unexpected that breeds should also exhibit variation in mortality and longevity. While shorter longevity per se may not necessarily be a welfare issue, a generally foreshortened lifespan in a breed that is accompanied by a high prevalence of a particular cause of death may reveal potentially serious welfare concerns and highlight scope to improve breed welfare. Survey data gathered directly from owners offer useful insights into canine longevity and mortality that can support the overall evidence base for welfare reforms within breeds.

Results: Mortality data on 5663 deceased dogs registered with the UK Kennel Club were collected from an owner-based survey. The most commonly reported causes of death were old age (13.8%), unspecified cancer (8.7%) and heart failure (4.9%); with 5.1% of deaths reported as unknown cause. Overall median age at death was 10.33 years (interquartile range: 7.17-12.83 years). Breeds varied widely in median longevity overall from the West Highland Terrier (12.71 years) to the Dobermann Pinscher (7.67 years). There was also wide variation in the prevalence of some common causes of death among breeds, and in median longevity across the causes of death.

Conclusion: Substantial variation in the median lifespan and the prominent causes of death exists across breeds. This study has identified some breeds with both a low median lifespan and also a high proportional mortality for one or more specific causes of death that should be considered as both potential welfare concerns as well as opportunities for improvement.

Keywords: Death; Healthspan; Lifespan; Longevity; Mortality; Pedigree; Predisposition; Purebred.

Fig. 1

Distribution of age at death from all dogs in the survey. The distribution of age at death (in years) from all dogs in the survey (n = 5663)

Fig. 2

Box and Whisker plot of age at death across breeds. Notched Box and Whisker plot of age at death (months) across breeds, for the 25 breeds with ≥50 deaths reported. ‘Notches’ in the boxes indicate the approximate 95% confidence interval of the median. The red dashed line indicates the median age at death of all dogs in the survey (n = 5663) of 124 months, and the thickness of this line approximates to the 95% confidence interval (122.57 to 125.43 months)

Fig. 3

Significant differences in proportional mortality within breed compared to overall. Significantly higher (red), and lower (green) within breed proportional mortality (WBPM) than overall proportional mortality (OPM) (P < 0.05) for the 25 most commonly reported causes of death among the twenty-five breeds with > 50 deaths reported with ≥50 reports (n = 3744 deaths)

Fig. 4

Box and Whisker plot of age at death across common causes of death. Notched Box and Whisker plot of age at death (months) for the 25 causes of death with ≥50 deaths reported. ‘Notches’ in the boxes indicate the approximate 95% confidence interval of the median. The red dashed line indicates the median age at death of all dogs in the survey (n = 5663) of 124 months, and the thickness of this line approximates to the 95% confidence interval (122.57 to 125.43 months)

Fig. 5

Diagrammatic representation of the 4 categories breeds may be assigned to based on longevity and high within breed prevalence of particular cause(s) of death. Longer and shorter lived (red) shown on vertical; binary category on horizontal indicating no cause of death at higher within breed prevalence (left) and one or more causes at higher within breed prevalence (right)