Health of Pug dogs in the UK: disorder predispositions and protections

Abstract

BACKGROUND Pugs are a brachycephalic dog breed that has become phenomenally popular over recent decades. However, there is growing concern about serious health and welfare issues in the breed. To augment the evidence-base on the comparative health of Pugs, this study aimed to compare the odds of common disorders between Pugs and all remaining dogs under primary veterinary care in the UK during 2016. A cross-sectional study design of VetCompass clinical records was used to estimate the one-year (2016) period prevalence for the disorders most commonly diagnosed in Pugs and non-Pugs. Risk factor analysis applied multivariable logistic regression modelling methods to compare the odds of 40 common disorders between Pugs and non-Pugs. RESULTS From a study population of 905,544 dogs, the analysis included random samples of 4308 Pugs and 21,835 non-Pugs. Pugs were younger (2.36 years, range 0.07-16.24 vs 4.44 years, range 0.01-20.46, p <  0.001) and lighter (8.95 kg, range 5.00-13.60 vs. 14.07 kg, range 1.41-85.00, p <  0.001) than non-Pugs. Pugs had 1.86 (95% confidence interval [CI] 1.72 to 2.01) times the adjusted odds of diagnosis with ≥1 disorder than non-Pugs. Pugs had significantly increased adjusted odds for 23/40 (57.5%) common disorders. These included: brachycephalic obstructive airway syndrome (odds ratio [OR] 53.92; 95% CI 36.22 to 80.28), stenotic nares (OR 51.25; 95% CI 24.93 to 105.37) and corneal ulceration (OR 13.01; 95% CI 10.50 to 16.11). Conversely, Pugs had significantly reduced adjusted odds of 7/40 (17.5%) common disorders compared to non-Pugs. These included: heart murmur (OR 0.23; 95% 0.13 to 0.14), lipoma (OR 0.24; 95% CI 0.11 to 0.55) and aggression (OR 0.31; 95% CI 0.21 to 0.47). CONCLUSIONS The current study highlights that predispositions outnumber protections between Pugs and non-Pugs for common disorders, suggesting some critical health welfare challenges to overcome for Pugs. Highly differing heath profiles between Pugs and other dogs in the UK suggest that the Pug has diverged substantially from mainstream dog breeds and can no longer be considered as a typical dog from a health perspective. Pugs have become phenomenally popular in the UK over recent decades. The breed has a flat-faced look (brachycephalic) that many humans find highly attractive and ‘cute’ but this flat face is also linked to several serious health problems. Consequently, there is growing concern about the welfare issues associated with the popularity and health issues of Pugs. To get a better overall perspective on the health of Pugs, this study aimed to compare the risks of common disorders between Pugs and all remaining dogs.The study collected clinical information from first opinion veterinary practices in the UK that were participating in VetCompass. Dogs were grouped as either Pugs or non-Pugs. Information was gathered from the clinical records on all disorders diagnosed in each group during 2016 and a list of the most common disorders in each group was generated.From 905,544 dogs in the overall study, there were 16,218 (1.79%) Pugs and 889,326 (98.21%) non-Pugs. Pugs (2.36 years, interquartile range [IQR] 1.16–4.53) were generally younger than non-Pugs (4.44 years, IQR 1.90–8.12). Pugs (8.95 kg, IQR 7.80–10.17) were also generally lower in bodyweight than non-Pugs (14.07 kg, IQR 8.15–25.20). From a combined list of 40 common disorders among both groups of dogs, Pugs had increased risk for 23 (57.5%) but had reduced risk for 7 (17.5%) disorders compared to non-Pugs. The disorders with the highest relative risk in Pugs included brachycephalic obstructive airway syndrome (BOAS) (× 53.92 risk), narrowed nostrils (× 51.25), eye ulceration (× 13.01), and skin fold infection (× 10.98). Disorders with the lowest relative risk in Pugs included heart murmur (× 0.23), fatty lump (× 0.24), aggression (× 0.31), and wounds (× 0.53).The study provides a broad evidence base on the positive and negative aspects of the health of Pugs. Disease predispositions were more common than disease protections, confirming the hypothesis that there are many critical health-related welfare challenges to overcome for Pugs. The widely differing health profiles between Pugs and other dogs in the UK suggest that the Pug has now diverged to such an extent from mainstream dog breeds that it can no longer be considered as a typical dog from a health perspective.