Labradors are not living as long as they used to

An interesting report by Jemima Harrison on the KC's recently published 2014 report on Longevity

Labradors in 2004 lived an average 12 years 3 months. Labradors in 2014 lived an average 11 year. In fact, longevity had decreased significantly in many breeds.

 

I read the article online a few days ago Pippa , very interesting and more than a little concerning too . I have a healthy respect for Jemima Harrison .

 

Depressing news. I have a friend who has just lost a Labrador cross at the ripe old age of 17! I also recall that scientists are working on doubling the life span of both humans and domestic pets. Personally I am happy with my 3 score years and 10 but it would be great news if science could extend the lives of our pets.

 

I read the report as well and it is very worrying that instead of increasing with the advances in veterinary medicine that life expectancy for our dogs is reducing

 

Just my personal opinion but I am very suspicious of all the strong chemicals in wormers, flea treatments, especially the spot on ones, that vets are pushing us to use on a monthly basis, they can't do our dogs any good.
I do wonder if these are contributing to shortening lives. In years gone by it was the norm to worm the dog once or twice a year and only treat for fleas if you saw them.

 

I agree with you mandyb. Though in the old days flea treatment was fiercer, but used only when needed. I can never understand why people put the flea treatments for prevention, when if they didn't use anything, their pet would probably not have fleas! In 45 + years of dog owning, I have only ever seen one flea on one dog.

I wonder if raw food has anything to do with it, though doubt it as dogs lived on all sorts of weird things years ago.

 

If I had to put money on it, I wouldn't put money on this.

I'd put my money on an ever decreasing gene pool of pedigree dogs. That's not so visible to us, but much more likely to be the problem in my view.....

 

The reports indicate medians, not averages (or means). You get the median by lining up all the ages of death from youngest to oldest and identifying the age that falls in the very middle. You get an average by adding up all the ages and then dividing by the number of dogs. Two different calculations.

It is much more meaningful to look at overall patterns of distribution rather than isolated stats like medians or averages/means. If you look at the graphs (histograms) from 2004 and 2014 showing the distribution of ages of death you can see that the median has gone down because more dogs are (reported as) dying at a younger age. But most dogs still live past 10 and the peak in 2014 was still at 12/13/14 years.

A less variable gene pool means that a species has less in its toolkit should the need to adapt arise. It's not in itself a problem otherwise. It IS bad to have harmful recessive genes in that gene pool, especially if they are disproportionately selected for, but that's a different thing.

 

While I only use flea and wormers when necessary I do know dog owners who have huge problems with fleas ticks and other parasites and have now choice but use all sorts chemicals, due to where they live.

I do agree with limited gene pool has an affect, but have been very lucky and got most of my dogs through to old age.

 

I wonder could being over weight contribute to short lives and the conditions this brings with it? Hardly ever see a normal weight Lab where I live. Whatever the reason it's very sad in this day and age of veterinary advances.

 

I lost both my two previous chocolate labs before the age of 10. One at 8 from a really aggressive lymphoma; despite treatment at the Royal Dick in Edinburgh he only lasted two months from diagnosis to his death. My last boy died really suddenly at just 9 years old, he just laid down and wouldn't get up as he was going out for a walk - OH got him home in a wheelbarrow but he died on the mat by the door within a few minutes of getting home. I couldn't face a post mortem for him but our vet thinks it is likely to have been blood clots.
For this reason I am trying to change lots of things for Ripple - different food (hopefully better quality), keeping his weight lower, more regular health and weight checks, watching how worming, flea and tick treatment affects him, and anything else I can do to ensure he remains healthy.
All three of the boys have been from different lines but I believe if I go back far enough in their pedigrees, being chocolates, I am always going to find common ancestors.

 

I too am concerned about giving dogs powerful wormers/flea treatment such as Bravecto,but there are some very nasty tick borne diseases around that affect both dogs and humans.

 

I think that the problem is, there are many, many rare recessive genes in every gene pool. And with permanently closed registers and therefore a continuously shrinking gene pool, more of these recessive genes will get together in every pedigree dog breed. Each time a new recessive disease appears, a test will be invented to detect it in our breeding stock, a test which will inevitably exclude yet more dogs from the gene pool and lead to more diseases.

My personal view is that ultimately the KC will have to open the breed registers in some shape or form, if it wishes to save pedigree dogs, something I suspect they won't do for many more years yet.

Population geneticist Carole Beauchat puts it much better than I can

 

Just realized Carole gives permission to copy and paste her explanation.

I think point 13 is the most poignant

1) All the useful genetic variation your breed will ever have was in the dogs that founded the breed. This genetic diversity is finite.

2) Each generation, alleles can be lost by chance (this is called "genetic drift") and also through artificial selection by breeders, who select for dogs with the traits they like and remove other dogs from the breeding population.

3) Because the stud book is closed, genes that are lost cannot be replaced.

4) So, from the moment a breed is founded and the stud book is closed, loss of genetic diversity over time is inevitable and relentless.

5) You cannot remove just a single gene from a population. You must remove an entire dog and all the genes it has.

6) You cannot select for or against a single gene, because genes tend to move in groups with other genes (this is called "linkage"). If you select for (or against) one, you select for (or against) them all.

7) Breeding for homozygosity of some traits breeds for homozygosity of all traits. Homozygosity is the kiss of death to the immune system. And, as genetic variability decreases, so does the ability of the breeder to improve a breed through selection, because selection requires variability.

8) The consequences of inbreeding (in all animals) are insidious but obvious if you look - decreased fertility, difficulty whelping, smaller litters, higher puppy mortality, puppies that don't thrive, shorter lifespan, etc. Genetically healthy dogs should get pregnant if mated. They should have large litters of robust puppies with low mortality. Animals that cannot produce viable offspring are removed by natural selection.

9) Mutations of dominant genes are removed from the population if they reduce fitness. Recessive mutations have no effect unless they are homozygous. Consequently, rare mutations are not removed; they are inherited from one generation to the next, and every animal has many of them.

10) If you create a bunch of puppies from your favorite sire, you are making dozens of copies of all of the bad mutations in that dog (which were never a problem before because they were recessive; see 9) and dispersing them out into the population. Now, a (previously) rare mutation will become common, its frequency in the population increases, and the chances go up that a puppy will be produced that is homozygous (has two copies of that bad allele) - and homozygous recessive alleles are no longer silent.

11) So, genetic disorders caused by recessive alleles don't "suddenly appear" in a breed. The defective gene was probably there all along. Make a zillion copies, and suddenly you have a disease.

12) Using DNA testing to try to remove disease genes from the breed will not make dogs healthier (see 2, 5, and 6).

13) The breed will continue to lose genes every generation (by chance or selection) until the gene pool no longer has the genes necessary to build a healthy dog.

14) At this point, the breed might look wonderful (because of selection for type), but it will suffer from the ill effects of genetic impoverishment - inbreeding depression, diseases caused by recessive alleles, increased risk for cancer, etc.

15) The health of individual dogs cannot be improved without improving the genetic health of the breed. The only way to improve the genetic health of the breed is to manage the health of the breed's gene pool.

16) Population genetics provides tools for the genetic management of breeds or other groups of animals. Breeders CAN improve the health of the dogs they breed if they understand and use them.

Copyright (c) 2013 Carol Beuchat
This document may be reproduced without permission if accompanied by the copyright information.


Last revision March 2015.

 

I guess this explains why dogs such as the Jack Russell Terrier plus crossbreeds and mongrels are generally more robust ? As an example , one of my late JRT`s lived to be almost 20 years old and until his heart gave out, never ailed a thing and only visited the Vet on about three occasions . I find the above article very depressing reading .

 

I think pedigree dogs are heading for a right old mess. And if you think flea treatments are the problem.....really? Really? Really? Read the report....read it.

 

I agree. You only have to look at that thread where we worked out which of our dogs were related to see that the world's supply of Labradors are coming from such a small gene pool. If I remember correctly, Ella - a Labrador bred in Australia - had the same great grandfather as a couple of forum members labs that were bred in the UK. Crazy stuff.

 

Interestingly Juno didn't share any generational links with other forum dogs, although I can trace her lines back to the original chocolate boy in the UK. Her lines are very mixed with dogs from various European countries. Is the problem more UK based as the data is only collected in the UK on a smaller gene pool?

 

No, the problem affects any isolated gene pool, and is exacerbated and sped up by the multiple matings of popular sires. This occurs in all pedigree breeds.

The smaller the gene pool the sooner you reach this point:

If you go back far enough, many registered pedigree dogs can trace their ancestry back to the UK, but the critical process of gene loss begins on the day the registers are closed. Wherever that may be.

Just to add, I love pedigree dogs, I have four. But I fear the KC's head in the sand approach to this issue may destroy the very thing they are trying to protect. The clock is ticking for all breeds, even popular breeds like ours.

 

what ideally if the regs were open would labs be out crossed too? Are we talking about changing aspect of the breed or health?