The number of Aussies is also uncertain because there are several registries.) (The exact number of SPs is unknown because the poodles are not registered by variety. There is no fool-proof way of establishing whether this sample is representative, but we now have on the order of 10% of the registered Clumbers from the last 25-30 years and probably a similar percentage of Standard Poodles. Internet with the project being advertised on breed-specific discussions groups and in breed newsletters. JA: Data on these three breeds has been collected almost exclusively over the LS: How have you conducted your survey to collect relevant information? If dogs are living shorter lives than they once were, this is likely part of the reason. Once the stud book is closed, inbreeding goes up - even if breeders are not deliberately inbreeding - simply because there are not enough dogs in a breed for every dog to have unique ancestors. One reason large dogs live shorter lives may be that they are often less numerous than the smaller dogs and are more subject to abuses such as the overuse of popular sires. The history of the breed will dictate the inbreeding and thus the lifespan to a greater extent than other factors, including size. My working hypothesis is that the major factor affecting purebred longevity is inbreeding depression. Aussies are a much more recent breed, at least with respect to kennel club recognition and one might hope that they are more diverse. In contrast, the SP has a much broader base, but a serious problem with popular sires (and a popular kennel) that has reduced genetic diversity considerably.
(When was the last time you heard of a Poodle being chained outside during bad weather? It may happen, but not often, and probably not by people who are involved with their dogs to the extent that they participate in Internet discussion groups or would visit the Diversity web site.) Both are old breeds, but the Clumber has never been as numerous and went through a serious bottleneck at the end of WW II. Clumbers and Poodles are probably among the least likely large dogs to be maltreated. I won't claim that these are representative of all purebred dogs, but they are all approximately in the same size range while having quite different breed histories. We started with the Standard Poodle (because I am a poodle owner and the subject came up on one of the discussion groups), and expanded to include Clumber Spaniels and Australian Shepherds because of interest expressed by individuals active in these breeds. Patronek's study seems to support these beliefs. Some of the questions I would like to attempt to answer include the one of whether mixed breed dogs live longer and also whether smaller dogs live longer. In fact, they generally underestimate the median lifespan because they do not account for the dogs that are still living while including contemporaries that have died. Furthermore, most breed surveys of health that have led to longevity estimates don't analyze the data correctly. ones that died very young have been forgotten. For example, a Swedish study (Bonnett et al., 1997) based on insurance claims ignores all past age 10 as they are no longer insurable, while an American study (Patronek et al, 1997) is based on deaths at veterinary teaching hospitals and will likely not include many that die of old age.īreed health surveys avoid these biases, but may be biased by either under-reporting of dogs that lived relatively problem-free lives or, particularly when it comes to looking at longevity earlier in the century, "selective memory" - i.e. Where such data exists, it has been collected by surveys, and the results depend on how representative the sample is of the population. This is not information readily available, as neither owners nor veterinarians are obliged to report deaths, and the kennel clubs keep no records. JA: First, we need to establish what the reasonable life expectancy for a domestic dog is. Is this what prompted your research and how do you go about proving if this assumption is true and if it is, what may be causing it? Armstrong, many breeders, not just of Boxers but of a number of purebreds, are concerned by an apparent decrease in their breeds average life span. I had an opportunity to speak with him recently about his research. Armstrong is head of the Canine Diversity Project and the list owner of the Cangen list (Canine Genetics list). of Biology, a geneticist and a dog fancier, is currently engaged in a research project on canine longevity and its genetic components.
But has the average life span of the Boxer really decreased and if so, what can breeders do to reverse this trend? John Armstrong, Ph.D., of the University of Ottawa dept.
Many Boxer breeders are concerned about the apparent decrease in the average life span of our breed. Research on Canine Longevity & Dog Breeding
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