Science Digest: What is the demography, common disorders and life expectancy of giant breed dogs in the UK?

14 August 2026

Despite human selection for large body size and giantism in dogs, there is limited benchmarking data on baseline health and longevity of giant dogs that could inform evidence-based discussions on limits that could be applied to giantism exaggeration.

A new study by researchers at the Royal Veterinary College and published in Companion Animal Health and Genetics, has examined the demography, most common disorders and life expectancy of giant breed dogs, using data from UK primary veterinary care at clinics participating in the VetCompass Programme during 2019.

The study included 28,345 giant breed dogs, representing 1.26% of all dogs owned in the UK, from 29 different breeds. The most common giant breeds were Dogue de Bordeaux (18%), Alaskan Malamute (13%) and Akita (10%). The median adult bodyweight overall of giant breed dogs overall was 49kg, ranging from Hungarian Kuvasz (31kg) as the lowest to Saint Bernard (65kg) as the heaviest.

From a random sample of giant breed dogs (4,316 of the total study population), 74% had at least one disorder recorded during 2019. This is higher than the proportion of dogs of all breeds (66%) recorded with at least one disorder in a previous VetCompass study during 2016, that used the same methods and data source. This could suggest that giant breed dogs have poorer health on average than dogs overall, or it is possible that lower levels of prophylactic care are being sought by owners of giant dogs because accessing veterinary care may be more logistically and financially challenging.

The most common precise-level disorders were otitis externa (8%), overweight/obesity (8%), and aggression (6%). The most common grouped-level disorders were dermatological (16%), musculoskeletal (14%) and aural disorders (12%). Among the most common precise-level disorders, Molossoid breeds had a statistically significantly higher prevalence of 16% of disorders – alopecia, skin cyst, lameness, otitis externa, aural discharge, and entropion – and statistically significantly lower prevalence of 19% of disorders – overweight/obesity, diarrhoea, aggression, dental disease, and periodontal disease, compared with non-Molossoid breed dogs.

Of the dogs that were recorded as having died during the study period, the median age at death was 8.94 years – substantially shorter than previously reported for dogs overall (12 years). This ranged from 4.77 years in the Tibetan Mastiff to 12.7 years in the Black Russian Terrier. Median longevity was significantly shorter in Molossoid breed dogs (8.42 years) than non-Molossoid dogs (9.97 years). The most common grouped-level precision causes of death were neoplasia (12%), collapse (9%) and heart disorder (4%).

The authors highlight that these findings of higher burden disorder and shorter lifespans in giant breeds raises concerns about negative impacts on the quality and quantity of life of these dogs, and provide evidence to support wider conversations about what levels of giantism in dogs should meet the threshold as an extreme conformation.

Limitations of the study include disorders being recorded as a binary variable (present or not present in the year of the study) and thus not accounting for severity or duration; inconsistencies in how disorders were recorded (either as formal biomedical diagnosis terms or broader clinical descriptors); and the potential for under-estimating true disorder status.

Take home message

Giant breed dogs have shorter lifespans, with an average age at death of 8.94 years, and a higher disorder burden compared to the wider population of dogs.

Reference

O’Neill DG, Curtis TJ, York GOJ et al. (2026) Giant dog breeds under primary veterinary care in the UK: demography, common disorders and mortality. Companion Animal Health and Genetics. 13, 4. https://doi.org/10.1186/s40575-026-00152-7