Dr. Becker then goes on to list specific breeds with reported median longevity that is lower in the 2014 survey compared with the 2004 survey.
As you can also see, however, the number of deaths reported is very different, and there is no statistical comparison to show whether the difference in the median or mean is significant. Why is this? Well, it turns out the data were collected in very different ways, they represent different methods and different dog populations, and the two surveys can’t legitimately be compared! Here’s what the actual authors of the survey have to say.
As we have seen many, many times in the past, Dr. Becker cares far more for her own narrative than for the truth, and she is perfectly comfortable misrepresenting or ignoring facts if doing so will make a story that fits her beliefs and her pitch. This bit of fear-mongering is yet another example.
It is true that the life expectancy figures in the 2014 survey are lower for many breeds than those in the 2004 survey. So, does this mean our pets are not living as long as they used to? Not quite. For one thing, life expectancy figures for some breeds are actually higher in the 2014 report than in the 2004 survey. For example:
Overall, the pattern of longevity in the two surveys is nearly identical, as you can see from these figures.
Ethics approval and consent to participate
Ethics approval was obtained from the RVC Ethics and Welfare Committee (SR2018-1652). No human data were included in the current study.
The sampling frame included 876,039 dogs with at least one clinical record during 2016 from 886 clinics in the VetCompass™ database. The geographic spread of the clinics with available postcode data included England (90.4%), Scotland (3.9%), Wales (3.7%), Northern Ireland (1.7%) and Channel Islands (0.3%). Initial screening identified 97,860 candidate death cases at any date from 1st January 2016 to 31st July 2020. Following a manual review of 32,390 (33.1%) of the candidate cases and excluding 72 dogs without a record of sex, the current study analysis included 30,563 (94.4% of candidates) confirmed deceased dogs. The success rate of the combined search terms to correctly identify deceased dogs was 94.6% (30,635/32,390).
Among the 30,563 dogs, 14,574 (47.7%) were female. There were 17,546 (57.4%) neutered dogs, of which 61.4% (n = 8951) were female. There were 23,963 (78.4%) purebred dogs, 6511 (21.3%) crossbred dogs, and 89 (0.3%) dogs without recorded breed information. Among 23,414 dogs of KC-recognised breeds, there were 5354 (22.9%) Gundogs, 1329 (5.7%) Hounds, 2451 (10.5%) Pastorals, 6055 (25.9%) Terriers, 3334 (14.2%) Toys, 2707 (11.6%) Utilities and 2184 (9.3%) Workings. In total, the analytic dataset included 263 ‘purebred’ breeds along with a ‘crossbred’ grouping. The number and percentage of each breed is in Supplementary File 1. There were 18 breeds included in the life table analyses, accounted for 50.6% of the population. The breeds were: American Bulldog (n = 126), Beagle (n = 171), Border Collie (n = 938), Boxer (n = 831), Cavalier King Charles Spaniel (n = 861), Chihuahua (n = 453), Cocker Spaniel (n = 1063), English Bulldog (n = 476), French Bulldog (n = 229), German Shepherd Dog (n = 1097), Husky (n = 153), Jack Russell Terrier (n = 1614), Labrador Retriever (n = 2481), Pug (n = 196), Shih-tzu (n = 635), Springer Spaniel (n = 785), Staffordshire Bull Terrier (n = 2347), and Yorkshire Terrier (1039). There were 5188 (17.0%) dogs recorded with health insurance.
Table 2 shows the overall life table for the UK companion dog population. The life expectancy at age 0 for UK companion dogs was 11.23 (95% CI: 11.19–11.27) years, with life expectancy decreasing with age. The probability of death at each year interval increased with age with an exception of year interval 1–2 (0.017) to 2–3 (0.016). The probability of death within each year interval remained at or below 0.02 before year 5, and the increase in the probability became prominent after around year 6–7.
Female dogs (11.41; 95% CI: 11.35–11.47) had a longer life expectancy than male dogs (11.07; 95% CI: 11.01–11.13) at age 0 (Tables S1 and S2 in Supplementary File 2). This trend towards greater annual female life expectancy persisted until individuals were 12 years of age, after which the life expectancy of both sexes became similar. When adding neuter status into consideration, a substantially higher probability of death in entire female (year 10 and before) and male (year 4 and before) than their neutered counterparts was observed (Tables S3 to S6 in Supplementary File 2). Entire females (10.50; 95% CI: 10.38–10.61) and males (10.58; 95% CI: 10.48–10.68) had a similar life expectancy at age 0 and life expectancy trajectory (Fig. 1), whereas both neutered females (11.98; 95% CI: 11.91–12.04) and males (11.49; 95% CI: 11.42–11.57) had an elevated life expectancy at age 0 when compared to their non-neutered counterparts, especially females.
Life expectancy and the 95% confidence interval for female and male dogs at different ages (year) under primary veterinary care in the UK.
Among the KC breed groups and dogs of breeds not recognised by the KC, Terrier had the longest life expectancy at age 0 at 12.03 (95% CI: 11.94–12.2) years, followed by Gundog (11.67 years; 95% CI: 11.59–11.76), non-KC recognised dogs (11.66 years; 95% CI: 11.56–11.76), Pastoral (11.20 years; 95% CI: 11.06–11.35), Hound (10.71 years; 95% CI: 10.53–10.89), Toy (10.67 years; 95% CI: 10.54–10.81), and Utility (10.06 years; 95% CI: 9.89–10.23) (Fig. 2). Working dogs’ life expectancy was shorter than all the other groups at all ages, with a life expectancy of 9.14 (95% CI: 9.01–9.27) years at age 0. However, comparative patterns of life expectancy between the breed groups at age 0 were not necessarily maintained later into life. For instance, Hound and Toy groups had a similar life expectancy at age 0 but diverged soon after this to reach a difference of 0.76 years (higher in Toy) at year 12. The life table of Hound ended at year 17 with a life expectancy of 0.52 (95%CI: 0.27–0.77) years, whereas Toy dogs at year 19 still can be expected to live for 0.66 (95%CI: 0.44–0.87) years. Supplementary File 2 (Tables S7 to S14) contains the life tables for the breed groups.
Life expectancy and the 95% confidence interval for dogs of different Kennel Club breed groups under primary veterinary care in the UK.
Life tables for the 18 breeds and crossbred varied widely (Table 3) and can be found in Supplementary File 2 (Tables S15 to S33). The last age of the life tables ranged from 11 in French Bulldogs to 19 in Jack Russell Terrier. Jack Russell Terrier had the greatest life expectancy at age 0 at 12.72 (95% CI: 12.53–12.90) years, followed by Yorkshire Terrier (12.54 years; 95% CI: 12.30–12.77), Border Collie (12.10 years; 95% CI: 11.85–12.33) and Springer Spaniel (11.92 years; 95% CI: 11.69–12.13). Compared to other breeds, many brachycephalic breeds (i.e., breeds of dogs with a short, flat face) had a relatively short life expectancy at age 0, with French Bulldog having the shortest at 4.53 (95% CI: 4.14–5.01) years, 2.86 years less than the value for English Bulldog (7.39 years; 95% CI: 7.08–7.69). To explore the longevity of the dogs of different breeds, we examined the earliest age at which the life expectancy dropped below 1.5 years (1.5 years was chosen because the life expectancy at the last year of all breeds was less than this value; Fig. 3). The life expectancy dropping below 1.5 years occurred in Chihuahuas at year 15–16, followed by Jack Russell Terrier, crossbred dogs and Yorkshire Terrier at year 14–15. English Bulldog was the earliest to reach the life expectancy of 1.5 years (year 9–10), followed by Boxer, French Bulldog and American Bulldog at year 10–11.
Relation between the life expectancy at year 0 and year interval in which the life expectancy became 1.5 in 18 breeds and crossbred under primary veterinary care in the UK.
The probability of death was lower in year 0–1 than year 1–2 in most breeds [American Bulldog (0.024; 0.065), Border Collie (0.012; 0.020), Boxer (0.005; 0.016), English Bulldog (0.040; 0.055), Cocker Spaniel (0.012; 0.013), French Bulldog (0.131; 0.136); German Shepherd Dog (0.013; 0.020), Husky (0.026; 0.047), Jack Russell Terrier (0.009; 0.009); Labrador Retriever (0.007; 0.009), Springer Spaniel (0.006; 0.006) and Staffordshire Bull Terrier (0.011; 0.012)]. Some breeds, including American Bulldog, Chihuahua, English Bulldog, French Bulldog, Husky and Pug had a probability of death before reaching adulthood (before year 230) much higher than the overall dogs (0.017 in year 0–1 and 0.016 in year 1–2).
This study presents the first cohort life tables for the UK dog population and dogs of different characteristics, including sex, neuter status, KC grouping and 18 breeds and crossbred dogs. These tables offer information about annual life expectancy and annual probability of death, which has been unavailable from conventional longevity studies in UK companion dogs to date. With the ongoing accumulation and accessibility of death information from Big Data resources such as VetCompass in the future, the construction of life tables for increasing numbers of breeds of dogs and also for other companion animal species should expand. The current study provides proof of concept for the development of (hypothetical) cohort life table construction in companion animals and also shares open-access R codes to contribute to these wider purposes (see “Materials and methods”).
Based on the mathematical and biological plausibility, a valid life table should exhibit the highest life expectancy at age 0 which decreases with age8,15,31. The probability of death may be higher in infancy as the immune system continues to mature in the postnatal period, for both humans and dogs32. In dogs, the immune system takes approximately one year for full maturity32. In the most recent life tables of humans in the UK, Australia and the US, the probability of death appeared the lowest in ages of 7–11 years (i.e., the onset of senescence) before showing an increasing trend until the end of the table (i.e., life)15,33,34. Our overall life table in dogs satisfied the condition of decreasing life expectancy and had the lowest annual probability of death (({widehat{q}}_{x})) before reaching adulthood at year 230, similar to the life tables in humans. Some life tables constructed in the current study did not follow this trend in the probability of death, for example, the life tables for neutered males and females. These life tables will be discussed below.
The life expectancy at age 0 reported in the current study for dogs under primary veterinary care in the UK in 2016 was 11.23 years (11.19–11.27), 2.47 years shorter than the life expectancy at age 0 (both 13.7 years) in the two life tables of Japanese dogs constructed using pet insurance and pet cemetery data, discussed above10,17. Differing data sources for the study populations might partially contribute to this substantial variation. Insured dogs may represent a subset of dogs that live longer than those without insurance, as they may receive more or additional veterinary care, due to alleviated economic constraints on the owners35,36. Moreover, dog breeds of high disease risk such as brachycephalic breeds might be under-represented in some insurance data than the general population due to the elevated cost to insure and special rules of reimbursement applied to these breeds in some insurance companies37,38. Breed demographics are likely to differ between these two counties. Breeds of toy or small size have a longer life expectancy than larger-sized dogs and are more common in Japan than in the UK1,5,10,17. In contrast, breeds of large and medium sizes, as well as brachycephalic dogs, are more popular in the UK39, which present shorter life expectancies. These demographic differences will influence country-level life expectancy estimates at age 0. However, it appeared that even within the same breeds, the life expectancy of dogs in Japan was considerably higher than those in the UK10, such as Labrador Retriever (UK = 11.77 and Japan = 14.1 years), Shih Tzu (UK = 11.05 and Japan = 15.0 years), Beagle (UK = 9.85 and Japan = 14.8 years), Pug (UK = 7.65 and Japan = 12.8 years), and French Bulldog (UK = 4.53 and Japan = 10.2 years). Variation in estimates may be partly due to sampling effort, as the life expectancy tables from Japan were created using a smaller sample size.
While female dogs (11.41; 95% CI 11.35–11.47) showed a longer life expectancy at age 0 than male dogs (11.07; 95% CI 11.01–11.13), this phenomenon was moderated by neuter status. Entire animals of both sexes showed similar trajectories of life expectancy from age 0 onwards. However, neutering was associated with an elevated life expectancy at age 0 for both sexes compared to their entire counterparts, and this longevity advantage from neutering was higher in female dogs than in male dogs. A similar survival advantage for neutered animals has been reported in several studies1,40,41, but most data, including the current study, generated these results by dichotomising dogs into neutered or entire without taking into account the duration of gonadal hormone exposure before the neutering. Neutered animals in these cited studies would have already lived to the age of neutering, biasing their life expectancy towards greater length, highlighted by the lowered probability of death at year 0–1 in neutered dogs. As veterinarians may often recommend early neutering for female dogs, sometimes before the start of the oestrus cycle42 or soon after the first cycle43, neutering of females may occur earlier in life than neutering for males43. Therefore, the gap of true life expectancy between the sexes due to neutering might be even wider than reported here. Neutering may also act as a proxy for stronger owner responsibility and better care, as it is often considered responsible dog ownership. Thus, neutered animals may benefit from additional survival advantages related to enhanced owner care43. Neutering may directly affect the risks of various health conditions and therefore shift life expectancy as a result41. In female dogs, neutering reduces or eliminates the risk of pyometra, a potentially life-threatening condition that occurs in 2% of entire female dogs under 10 years44. Neutering is linked to a reduced risk of tumours within reproductive organs and various cardiovascular diseases, but an increased risk of joint disorders and several types of tumours such as lymphoma and hemangiosarcoma, especially in females45. Due to the complexity stated above, our life tables for neutered dogs should be interpreted with great caution.
For the 18 breeds and the crossbred category, the number of years contained in the tables, life expectancy and the probability of death at different ages varied widely. Relatively shorter life expectancy at specific year points can be taken as evidence that events and processes eventually leading to mortality are occurring earlier in life in these populations than some other populations, so these populations may have generally poorer health than some other populations30,46. If the distribution of external factors that may lead to differences in the life expectancy and the probability of death (e.g. severe disease epidemics and/or substantial differences in the level of veterinary and owner care) do not depend on the breeds, it may be safe to assume that part of the life expectancy difference is contributed by internal factors driven by the genetic make-up of the breeds. Breed predisposition to particular disorders is a well-identified phenomenon47. Breeds that show high levels of potentially life-threatening predispositions that start early in life are likely to have a higher probability of death at younger ages and therefore a decreased life expectancy. Indeed, four brachycephalic breeds (French Bulldog, English Bulldog, Pug and American Bulldog) that showed the shortest life expectancy at year 0 of all 18 breeds in our results are also reported with several predispositions to life-limiting disorders that occur early in life, such as brachycephalic obstructive airway syndrome, spinal disease and dystocia48,49,50,51.
Lifespan variations between breeds were explored by examining the association between the breed life expectancy at age 0 and the year interval at which the life expectancy reached 1.5. Generally, life expectancy at age 0 and the year interval in which the life expectancy became 1.5 were positively associated, as would be expected: breeds that lived longer were also older when they reached an age with 1.5 years of life expectancy. However, although Chihuahuas showed a life expectancy at age 0 of only 7.91, the year interval in which the life expectancy became 1.5 was year 15–16, the highest of all the breeds, indicating a high variation of lifespans among Chihuahuas. A lowered life expectancy at age 0 suggests an increase in mortality of younger-aged dogs (whose mortality is usually low), and the life expectancy becoming 1.5 years at a later age implies more dogs also living to advanced age; both increase the variation of lifespans11. In our results, the probability of death before year 13–14 was higher (and much higher before year 4) in Chihuahua than for dogs overall, which became lower after that. It was also observed in French Bulldogs that a low life expectancy at age 0 (4.55 years) and relatively old year interval when the life expectancy became 1.5 years (year 10–11, more than twice as long as the life expectancy at age 0) and that their probability of death was rather uniform across all ages. However, although the high variation of lifespans of French Bulldogs could be due to high health risks in early life49,50,51,52 and a relatively small sample size (n = 232), it may partly be attributed to recent soaring popularity53. The number of KC registered French Bulldogs in the UK rose steeply from 2771 in 2011 to 39,266 in 202039, suggesting that the population of French Bulldogs (and other breeds sharing a similar rising trend in popularity) in our dataset are biased towards younger dogs that contribute proportionately more deaths in younger ages in the life table. In contrast, breeds with a decreasing trend in popularity may have an underestimated probability of death at younger ages, resulting in overestimated life expectancy. Previous studies have also shown the rising popularity of certain breeds and the association of rising popularity with lower median age54,55,56,57,58,59,60. Hypothetical cohort life tables are more susceptible to the influence of population instability, which is common in dogs due to sudden and dramatic fad-like changes in breed popularity61. This can be avoided by implementing current or real cohort life tables instead if such data were available.
Thirteen of the 18 breeds had a lower probability of death in year 0–1 than year 1–2 in the life tables, some slightly and others substantially. This finding goes against the evidence that mortality is higher in puppy (0–26 weeks) and juvenile (27–52 weeks) periods than young adult period (1–2 years) and empirical results in human life tables15,33,34. This may, in part, be due to substantial puppy mortality occurring before individuals can be registered to a primary veterinary clinic resulting in these deaths not appearing in the current dataset. A more accurate estimation of life expectancy from birth would be possible if all the currently unavailable puppy mortality information could be recovered.
Life tables in companion animals offer extensive applications. Similar to a common application for human life table studies, comparison between life tables can support deeper insight into the health of dogs of differing demographics such as sex and breed over time and space62,63. When life tables are generated periodically for a specific population, changes in the life expectancy and the probability of death at specific ages can indicate changes in the general health and welfare of the population. Comparison of life tables among the populations of different traits such as breed or conformation can also identify less healthy or more vulnerable populations62, as demonstrated in our study (especially for breeds). Advanced life table modelling can offer useful information allowing the quantification of disease burden on health and welfare in human and companion animals2,64,65. Quantification of disease burden is important because it can assist with the prioritisation of health conditions for targeted reform66,67,68. Coupling these findings with cost-effective analysis on disease prevention and control can assist to allocate resources to priority health conditions and achieve efficient improvements in the health and welfare of the overall population69. The value of disease burden quantification has been demonstrated by the Global Burden of Disease project of the World Health Organization to improve human health70. The Global Burden of Disease uses the Disability-Adjusted Life Year framework that incorporates life tables as part of the methodology to quantify the burden of many diseases (369 diseases and injuries in 2019)64,65. The Disability-Adjusted Life Year has been adapted into the Welfare-Adjusted Life Years (WALY) to quantify the burden of common diseases on dogs welfare2. The WALY constitutes two elements, (a) years lived with impaired welfare, which is the years having a certain disease weighted by its severity and (b) years of life lost due to the premature death caused by the disease or resulting assisted death. Future life table modelling that accounts for comorbidity and demographics of dogs can offer information about years of life lost based upon the life expectancy at the age of death for the individual animal affected.
Life tables highlight the value of interpreting life expectancy annually, especially at older ages, where differences in life expectancy between ages become narrower. Thus, the current authors propose that life table literacy is important for veterinary professionals, shelter staff, and dog owners because it can optimise decision-making and subsequently can positively impact dog welfare. Life table literacy will promote realistic expectations for the life expectancy of dogs at different ages, helping to make treatment plans for illness and end of life decisions. Shelters and charities can also incorporate this information in the adoption process ensuring that potential dog owners understand the expected length of ownership commitment required for dogs of different breeds, ages, and neuter status.
With the foundations for canine life table science built by the current work, we hope to generate further examples of life tables for both dogs and cats using the VetCompass data in the future. The current study provides a proof of concept that can support future research looking to construct life tables for dogs and cats as a periodic recurring endeavour. Consequently, changes in the life expectancy, mortality, and health of companion dogs and cats can be tracked similarly to how it is in human demography15,16. For future life table construction, we hope to incorporate other sources of information such as KC annual registry data and dog insurance data with further modelling, which will help to produce even more accurate life tables71.
This study had some additional limitations to those discussed above. Firstly, the high frequency of euthanasia in companion dogs highlights the potentially underestimated life expectancy compared to unassisted death72. This is especially biased by euthanasia undertaken for non-life-threatening reasons such as undesirable behaviours, economic reasons or convenience35,73. Consequently, differing cultures between countries for euthanasia in dogs might substantially influence national life tables. Another limitation is the sole inclusion of primary veterinary practice-attending dogs. Thus, our results might be less representative of unowned dogs or dogs not attending veterinary clinics. Also, some dogs that died at home or in emergency out-of-hours clinics might be excluded from the current data, although the data did capture all deaths away from the clinics that were reported by owners to the veterinary clinics at any time. Lastly, the sample sizes for some of the 18 breeds (e.g. American Bulldogs, Beagle, English Bulldog, French Bulldog, Husky and Pug) were relatively small, resulting in life tables with reserved confidence.
The current study has produced the first life tables for dogs in the UK, reporting annual life expectancy and probability of death for the UK companion dog population, dogs of different sex and neuter status, breed groups and also for 18 breeds and crossbred dogs. We report an elevated life expectancy in neutered dogs compared to entire dogs and wide variation in life expectancy between breeds, with Jack Russell Terrier and Yorkshire Terrier having the highest and some brachycephalic breeds showing the lowest life expectancy at age 0. The construction and application of life tables offers great potential for companion animal health and welfare sciences but is still in its infancy. Life tables generated in the current study promote not only a better understanding of the life trajectory of dogs but also offer several applications for the veterinary profession and research to improve the health and welfare of dogs.
The datasets generated and analysed during the current study are publicly available on the RVC Data Repository at https://rvc-repository.worktribe.com/output/1558210. R codes for cohort life table construction and all life tables generated by the current study can be found at https://github.com/kendyteng/cohort_lifetable.
How LONG Do DOGS LIVE? The LIFE EXPECTANCY of Dogs
Larger animals tend to live longer than smaller ones (most of the time). Think about it. Humans live longer than cats, which live longer than a rat, which lives longer than a fly. But why isn’t this true when it comes to animals within their species?
A person who weighs 150 pounds will most likely live longer than a person who weighs 300 pounds. They live longer because of increased health risks for a person who weighs 300 pounds.
When it comes to dogs’ life expectancy, how can you compare a Great Dane to a Chihuahua? Their anatomic builds are completely different, and their lifespans reflect this. Beyond size, is there an average age of a dog based on breed or other factors? Yes. Let’s explore the answers to these questions: “how long do dogs live?” and “what is the dog lifespan by breed?” Table Of Contents
Want to know how you can help your pup live a longer, happier life? Below are some factors that help determine a canine’s lifespan.
As the owner, you can impact the care you provide for your dog. A dog with a proper, nutritious diet and exercise can live longer than one without. In addition, taking your furry friend to annual wellness exams at the veterinarian and getting her booster shots can result in a healthy dog with a longer lifespan.
Research shows that larger dogs live for a shorter period of time when compared to smaller ones. For example, an Irish Wolfhound (average 115 pounds) has an average lifespan of seven years, while a Jack Russell Terrier (average of 15 pounds) can live up to 13-16 years.
Inbreeding can reduce the lifespan of canines. Cross-breed dogs have a longer lifespan in comparison. Inbred dogs have a risk of carrying genes for illnesses that are common to that specific breed. Further, “mutts” who have at least two breeds tend to have the least health problems and live longer than their purebred counterparts.
Spaying and neutering a puppy at a relatively young age can positively affect a dog’s lifespan. Most studies recommend surgical sterilization before five months of age for small breed dogs and 12-15 months for larger breed house dogs.
Studies suggest that these surgeries can help reduce the risk of some types of cancer in dogs — especially cancers affecting the ovaries, breast, and testicles.
Recent studies show that these benefits may or may not be completely accurate, but there is no question that your life will be easier without a litter of puppies, and this will be less stress on your pup, which could mean a longer life.