Originally Posted by
Jackbox
Not sure who says Xbreeds are healthier than Pedigrees?
The solution is buying from health tested parents and as many Xbreeds are purposely bred these days.. it stands to reason they will be or could be doubling up on genetic problems.
I have had mongrels, and purebreds all my life, cant say one was healthier than the other, individual dogs all having individual life spans and illness.
With respect to KCJack, it would be interesting to know where her dogs came from, whether they came from health tested stock, from reputable breeders.
As the where they come from will have more to do with their health than what they are!!!
I think most people would say crossbreeds are more likely to be more healthy than pedigrees. These thoughts are backed up by what we know aout genetics. I don't think anyone would say all crossbreeds are healthier than all pedigrees - that's just daft. Inbreeding does cause problems. This is well documented, and is the reason we don't reproduce with our parents/close relatives, and the reason the several species have developed mechanisms to prevent against inbreeding for their survival.
"The domestic dog, Canis familiaris, has
more naturally arising inherited diseases
than any other species, with the exception
of man."
Taken from:
http://bfgp.oxfordjournals.org/cgi/reprint/4/2/112
I'm afraid, the solution isn't as easy as buying from health tested parents. It can help, certainly, but there simply arent enough tests for all the inherited diseased pedigree dogs can suffer from (over 400).
Originally Posted by
ClaireandDaisy
Isn`t this an Old Wives Tale? Do you have any studies for it? Maybe insurance companies keep these sort of figures?
The problem with this sort of research, is that as far as I know, no-one has done any comprehensively, as funding is a problem. The Kennel Club should be doing it, but I don't think what they'd find would be too popular. There is a lot of research done on dogs, but this is because they're a good model on which to study human genetic disease, partly because they suffer from a lot of diseases, and are inbred, which makes studying the genetics behind the disease easier.
http://171.66.122.45/content/10/9/1271.full
So, the difference between pedigrees and most crossbreeds is the extent of inbreeding, and the reason inbreeding has negative effects is due to increased likelihood that a dog will inherit two of the same recessive genes. These may be disease genes, or genes for another trait (i.e. traits characteristic of a breed, such as coat colour or conformation). This is well documented. Outbreeding (introducing unrelated genetic material), by contrast means that the parents are
less likely to share genes and therefore
less likely to contribute two of the same recessive alleles of a gene. The reason breeds are associated with health problems is because along through selection for breed charcteristics, there is an decrease of genetic diversity within that breed, which may well inadvertently lead to accumulation of disease genes (See the high incidence of genetic disease in royal families). Of course, as i said above, it is rarely as simple as this, but it is undoubtedly true that preserving genetic diversity within a species is extremely important for it's overall health. Animal species which have succumb to extinction often have had population bottlenecks, that is, a severe reduction in genetic diversity (now extinct species of cheetah). Some species are currently affected by population bottlenecks and are suffering problems as a result of lack of diversity. Here are a couple of examples:
"The Tasmanian devil (Sarcophilus harrisii) has suffered significant population decline in recent years
due to Devil Facial Tumour Disease (DFTD), an infectious cancer which is transmitted between
individuals through biting. The low genetic diversity in Tasmanian devils has increased their
susceptibility to this disease and animals usually die within
months of clinical expression. Average sightings have declined
by 53% over the past 10 years and the current prognosis is
extinction of the species within 25-30 years."
Taken from:
http://www.cbsg.org/cbsg/workshoprep..._phva_2008.pdf
http://www.sciencedirect.com/science...4d71b5ec6fa9e5
"Genetic basis for species vulnerability in the cheetah":
http://www.sciencemag.org/cgi/conten...;227/4693/1428
So the fact that we know this, and the fact that research institutes are willing to spend £millions on studying the genetics and diseases of pedigree dogs, as opposed to crossbreeds, makes me feel that it's significant. Also, The Kennel Club has only closed genepools in relatively recent times, and we're already seeing lots of conditions cropping up in pedigrees - I believe the gap between the health of pedigrees and mongrels will continue to increase, ie. we might not be seeing the worst of it now.
Originally Posted by
ClaireandDaisy
But how do you know?
I'd love some reliable statistics too, but for now, I'm going on what we know about genetics, and the research that's already been done. Also, the very fact that individual breeds are associated with health issues (dalmatians with deafness, GSDs and HD), is an indication that the very rigid way dogs are registered is not doing them any favours... and before someone says it, I
know not all dalmatians are deaf, and not all GSDs have HD, and not all pedigrees are unhealthy.. I'm simply giving some reasons how it can be deduced that pedigrees are likely to be less healthy than crossbreeds.
http://www3.imperial.ac.uk/newsandev...8-2008-12-22-2
I wonder how these stats can be made available, and why they're not currently? Could vets be holding back this kind of info? Would the KC have anything to do with it? Why aren't they publising this sort of information? I can but speculate! Aside from that, the kennel I used to work at, the dogs on permanent meds were more likely to be prdigrees, but as people have said, this sort of information is not conclusive in any way, and the only surveys on this I've seen, have been really small, and badly analysed. If anyone has links to any better ones, I'd love to see them.
It may not look to too bad at the moment, but I am worried about the future of pedigree dogs, and how long they can go on as they are currently. I love my pedigree dogs, but I think we could be doing a lot more to ensure breeds have a bright future.