Age and Cause of Death of Bernese Mountain Dogs in Australia.

by Carol Eastley 22/5/2003

The purpose of this study was to develop an understanding of the longevity of Bernese Mountain Dogs in Australia. What do we say to puppy buyers when they ask "How long will my dog live?" Which causes of death are most commonly reported and perhaps deserve our greatest attention?

Sample size and quality.

Based on the assumption that the average age at death would be similar to that reported from other countries (7.5), and with the aim of acquiring as much data as possible it was decided to limit the data to dogs that were born 10 or more years ago. Deaths earlier than 3 months of age were also excluded.

The study only includes Australian bred dogs. Imported dogs have been subjected to stresses which might affect their longevity including the quarantine period, and chemical and biological treatments which Australian bred dogs don't experience.

101 dogs represent approximately 20% of the population at the time based on ANKC registrations statistics.

Is the sample random? No
The sample was solicited/provided voluntarily. It is quite possible that breeders/owners who choose to submit information could have an influence on the health of their dogs. Dogs that died y oung are most likely to be under represented because of the time factor- ie lost information. But on the other hand early deaths have a bigger psychological impact and the puppy owner is more likely to inform the breeder. Older dogs may be under represen ted simply because quite a few are still alive in the 11-14 age group.

A couple of breeders have been kind enough to provide information on whole litters which should go some way toward balancing the sample. A couple of the larger kennels are under-represen ted, however many of these lines appear in dogs from other kennels, and some small kennels are over represented.

Method

A simple database was constructed to collate the information. Where the date of death was provided the age was calculated to the nearest 6 months, as most people seem to report age to the nearest 1/2 year. Cause of death was given for 76 Bernese. The quality of this information is extremely variable as expected, and I've tried to illustrate cause of death from a number of different angles.

I've chosen to graph most of the data in order to provide visual impact. Please be patient while the graphics load.

 

Age at Death

The most common age at death was 10 years.
The average age at death was 8.42 years.

There are still a number of dogs alive in the 11-14 year group, so the tail end of the graph will fill out with time

Summary statistics

Mean 8.423267627
Standard Error 0.264802901
Median 9
Mode 10
Standard Deviation 2.66123622
Sample Variance 7.082178218
Kurtosis 1.559083212
Skewness -1.018245315
Range 14.25
Minimum .25
Maximum 14.5
Sum 850.75
Count 101

 

Cumulative graph

This graph shows the rapid decline in numbers between the ages of 8 and 11. Approximately 20% of dogs died before the age of 8 (in other words 2 out of 10), 63% died at 8,9,10, and then the remaining 17% died at 11-15 years.

 

Life Expectancy Table

The life expectancy table is included for your entertainment. It is based on the pattern provided by the dogs from this study and is simply an indicator of how much longer the average dog might live if it reaches a particular age.

 

Causes of Death

For individual causes of death, the numbers are very small. Only simple averaging and column graphs have been used for illustration. I've tried to refrain from making the data say more than it does. eg I've made no assumptions as to what type a tumour may have been unless it was specified. However a tumour in the heart would be listed as a tumour.

 

Causes of Death Number
Cause not given 24
Arthritis/paralysis 7
Bloat 4
Old Age 7
PTS not specified 2
Accident 8
Infection 4
Immune 3
Heart 4
Stroke 2
Kidney/bladder disease 4
Ulcer 1
Whelping 1
Temperament 2
Cancer tupe not specified 8
Histio 7
Tumour 8
Bone/breast/lymph cancer 5
Cancer/tumour combined 28

 

Area of Body affected Number
Heart 6
Accident non-specific 7
Bone 2
Hips 3
Stomach 5
Bladder 1
Liver 4
Reproductive Organs 3
Throat & Lungs 2
Infection non-specific 2
Immune system 4
Hind quarters 2
Kidney 2
Brain 5
Spine 3
Foot 1
Spleen 1

 

Average Age of Death  
Cancer/tumour combined 8.22
Arthritis/paralysis 8.07
Bloat 9.75
Old Age 12.29
PTS not specified 9.00
Accident 5.94
Infection 3.94
Immune 8.33
Heart 8.5
Stroke 11.00
Kidney/bladder disease 9.13
Ulcer 9.00
Whelping 4.50
Temperament 8.75
Cancer tupe not specified 8.63
Histio 5.86
Tumour 8.81
Bone/breast/lymph cancer 8.30
Cancer/tumour not specified 8.63

Conclusions

The most common age at death was 10 years.
The longest lived Bernese in this study was 14.5 years.
The average age at death was 8.42 years.
More than 60% of Australian Bernese in this study died between the ages of 8 and 11.

The most common cause of death at 28% was combined "cancer or tumour".
However when broken down as reported no particular cause of death stood out.
Accidents were also a significant cause of death.

We need to know more accurately the cause of death in dogs that die in the 8-10 range. This is such a large group of dogs, that it surely must be the easiest to have an effect on. Dogs that die under the age of 11 are not dying from "old age". I think we should make it our goal for the most common age of death to become 12 years of age.

Many thanks to people who provided information on their beloved pets for this study.

 

return to Home Page