The difference between “pedigree” and “pure” dogs.
A pedigree is nothing more than a record of parentage kept
by kennel clubs. It is basically a family tree going back some generations.
A pure dog of any breed is one that shows no evidence in its
DNA of any other breed amongst its ancestors. It needs to be understood that
there are no genetic markers that prove a dog is pure.
There is no requirement for pedigree dogs to have been
checked using DNA analysis to prove the purity or health of any of the dogs. This
is not surprising since until recently accurate DNA testing was not available. Most
breeds have only come into being within the last couple of hundred years
through human manipulation to obtain a desired function, look, or temperament. Some
breeds were established by mixing other breeds to obtain the desired type of
dog. Pedigree dogs have gone through a genetic bottleneck with loss of natural
genetic diversity and often an increase in genetic health issues as an
unintended side effect. Since breed registers are closed and not all dogs born
are used to breed, the genetic diversity is likely to decline further. Some
breeds such as the brachycephalic (short snouted) ones are in reality deformed
and have breathing problems and should no longer be bred regardless of them
having a pedigree. Others have been bred with a view to wining shows, which of
course helps to sell them, but also in some cases may have a negative impact on
their health. Any attempt to now eliminate these genes that are associated with
health issues would of course also lead to further reduction in the overall
genetic diversity of pedigree dogs in already closed pools, so is a complicated
process. Other factors may also be involved and the likelihood of a dog
developing health issues can be seen as a sliding scale, with absence of a
given problem occurring being lowest in a dog without the associated gene, with
an increasing chance in a dog with one copy of the gene (considered a carrier)
to a greater risk in those with 2 copies of the gene (at risk). In some breeds,
such as the Rhodesian Ridgeback, there is even a requirement in the breed
standard that they have what is known to be associated with a risk. Open dermal
sinus that need surgical intervention, have a greater chance of developing in
ridged dogs and yet some breeders have gone on public record saying they
euthanize any dog born without a ridge ie. the healthier ones may be killed!
But hey they have a pedigree and come from “responsible” breeders.
Embark describes how breed analysis is done as follows:- “Breed
analysis is based on comparing your dog’s DNA with the DNA of dogs from over
250 breeds, types and varieties. All dogs are related and share some DNA.
Siblings share lots of their DNA (half of it in fact), cousins share a bit less
(an eighth), and so on. Because dog breeds are made up of a closed group of
dogs, all dogs in that breed share a lot of their DNA, typically about as much
as second cousins, though it varies by breed. Different breeds that are closely
related share somewhat less DNA, and dogs from very different breeds share even
less DNA (but still much more DNA than either dog shares with a cat).
DNA is inherited in pieces, called chromosomes, that are
passed along from parent to offspring. Each generation, these chromosomes are
broken up and shuffled a bit in a process known as recombination. So, the
length of the segments your dog shares with his ancestors decreases with each
generation above him: he shares longer segments with his mom than his grandma,
longer segments with his grandma than his great-grandma, and so on. We can use the length of segments a dog shares with our
reference dogs to see how many generations it has been since they last shared
an ancestor. Long segments of DNA that are identical to known purebred dogs
tell Embark's scientists that Roxx has, without a doubt, a relative from that
breed. By testing over 200,000 genetic markers, we build up his genes one DNA segment at a time, to learn the
ancestry with great certainty. Other dog DNA tests look at fewer than 10,000 genetic
markers and have to take a guess at breed ancestry based on that. In a small
proportion of cases, we find dogs that don’t share segments with other dogs we
have tested, indicating the presence of a rare breed that is not part of our
reference panel or possibly a true "village dog" without any purebred
relatives at all. In these rare cases we contact the owner to find out more and
let them know about their unique dog before they get their results. With this
in-depth detective work, we are pushing science forward by identifying genetically unique groups of dogs.”
Many freeborn pariah dogs, also known as landrace or village
dogs worldwide have been shown to be 100% pure. They seldom have a pedigree,
often have fewer health problems, since
natural selection often means less chance that those with health issue would
survive, and they maintain the wide genetic diversity that nature gave them.
These dogs are not mixed mongrels or strays, but of course those do occur as
well. In general they also have lower coefficient of inbreeding than do most
pedigree dogs, a factor that also makes them more likely to be healthy.
Copy and paste the following links to your web search to see
the results of just 2 of the natural pariah Arabian desert dogs of the type
used to establish the human controlled Canaan breed. There are links on them to
other similar dogs and there is no reason anyone looking to adopt a dog from
the middle east could not get it tested if they are concerned about what other
dogs may be in its genetic makeup or that it could have hidden health issues .
The OFA testing done on pedigree dogs in the USA is not expensive and few
pedigree dogs used to breed have been tested by Embark for the over 150
potential genetic diseases they may or may not have.
embk.me/roxx2
embk.me/sasha37
Some of the first DNA breed testing, as well as some still
current, use older technology and were not accurate but newer ones currently
look at 200 000 or more alleles with good accuracy. Embark remains the only one
with data on “village dogs”. Embark also
does have DNA identification for Canaan dogs but sadly for some reason no owner
has allowed the data to be shown publically, for reasons known only to them.
With less than 30 dogs having been tested no overall statistical data can be
provided on pedigree Canaan dogs.
So what do we know of the health of pedigree Canaan dogs. Well
we know that a famous Italian breeder stopped breeding for a while after it was
found that all her inbred dogs had a health issue. We know that “My dog DNA” (https://mydogdna.com/) has identified a renal
disorder in pedigree Canaan dogs known as hyperuricosuria (HUU). Hyperuricosuria
(HUU) is an inherited disorder in dogs that can cause hyperuricemia and
predisposes affected dogs to the development of urolithiasis (urate stones) in
the kidneys and bladder. The disease is very common in Dalmatians but is seen
in several other breeds as well. Hyperuricosuria is inherited in an autosomal
recessive manner. The Embark DNA analysis tests for this as well as over 150
other potential genetic health issues. This condition causes kidney and bladder
stones composed of urate; if caught early, it is responsive to dietary
management. Uric acid is an intermediate of purine metabolism. In most dogs,
uric acid is converted to allantoin, an inert substance that is then excreted
in the urine. Dogs with HUU have defects in the pathway that converts uric acid
to allantoin. As such, uric acid builds up, crystallizes and forms urate stones
in the kidney and bladder. While hyperuricemia in other species (including
humans) can lead to painful conditions such as gout, dogs do not develop
systemic signs of hyperuricemia. Urate stones are invisible on X-rays and must
be diagnosed by a veterinarian via ultrasound or urine sediment analysis. If
left undiagnosed, bladder stones can lead to urinary obstruction, which can be
life threatening.
In the USA a number of Canaan dogs have been tested by the
Orthopedic Foundation for Animals (OFA) looking mainly for orthopaedic issues
and that they recommend testing pedigree Canaan dogs for Hip dysplasia, Elbow
dysplasia, Patella luxation, Eyes, Auto immune thyroiditis
They also say “The breed
specific list below represents the basic health screening recommendations. It
is not all encompassing. There may be other health screening tests appropriate
for this breed.”
When ranked with position 1 being the worst, Auto- immune
thyroiditis in Canaan dogs Ranked 31 out of 114 breeds where more than 50 have
been tested. 6% were positive of 167 tested. 13% were abnormal and a further
6.6% gave equivocal results. At any point in the dogs life a negative result
does not rule out future development of this occurring thus in the dogs life
time it is possible a greater number could be effected.
Degenerative myelopathy was worse, ranked 22 with only 55%
giving normal results and 38% were carriers.
Degenerative myelopathy of dogs (also called chronic
degenerative radiculomyelopathy) is an
inherited disease that occurs in German Shepherds, Pembroke Welsh Corgis, Boxers,
Rhodesian Ridgebacks, Chesapeake Bay Retrievers, and other breeds. Affected
dogs exhibit degeneration of nerve fibers (axons) and the sheath that surrounds
them (myelin). Dogs with the condition are usually older than 8 years of age
and slowly start to display nonpainful incoordination and weakness of the hind
limbs. It can be confused with orthopedic disorders (such as arthritis), but
dogs with degenerative myelopathy have difficulty sensing and placing their
feet normally whereas arthritic dogs do not. Unfortunately, there is no
specific treatment for the disease, and most affected dogs are euthanized
within 1–3 years.
The testing done by the OFA is very limited looking at only
8 issues compared with over 150 known genetic health issues so has very limited
value.
All breeders are individuals and most responsible ones do
take steps to be careful the dogs they breed are healthy as far as possible but
statements that Canaan dogs bred for sale are somehow healthier than those
directly introduced from rescue groups simply do not stack up. The Canaan breed
was established from some 30 founders simply collected from the local pariahs,
mostly from Israel but one of the first in the UK came from Jordan after an
overland move to Libya with Bedouin. Myrna Shiboleth also has added dogs
rescued in Jordan and yet says "Rescue group that rescues street dogs,
love to call them Canaans, but they are not". Yes it is true that most
rescue groups give an identity to their dogs because potential adopters ask and
they may be wrong and some do think that every dog found in the middle east is
a Canaan which is not the case. No one can claim none of them are Canaan dogs
without even seeing them anymore than they can all be called Canaan’s. A number
of shelters in the USA also tag dogs as Canaan dogs which in some cases have
probably not been bred by Canaan breeders and have not come from the middle
east. It has been claimed that some 200 rescue dogs are imported to the USA
annually and that 60 (a guess) dogs labelled as Canaan dogs have asked (and
been rejected) for help in homing them through the Canaan rescue network. No
supporting facts were presented to show that these dogs all originated in the
middle east so this claim is meaningless.
How is it that in the USA it is claimed that all responsible
breeders will always take back a dog they have bred if no longer wanted and yet
there is a need for a Canaan Dog rescue that admits to “ 4-5 legitimate Canaan
rehome requests for help in a year “ out of an estimated “50 to 70 true Canaan
pups are born yearly”. That’s as many as 10% needing to be re-homed and not
taken back by the breeder!
People involved in trying to home dogs in the middle east
are NOT profit making groups that rely on selling deliberately bred dogs for a
living. They manage entirely on fund raising and help from volunteers and some
have considerable debt at veterinary practices that have to make money to stay
in practice but still do all they can to help.
One of the often stated points of pedigree Canaan dogs is
that they are a primitive (I prefer ancient) type so why is it claimed by a
Canaan person that this is some sort of bad thing in a middle east dog?
The USA, like most countries, has its own health checks and
requirements before a dog can be imported and while there has been a case of
imported rabies as a result of false documentation from Egypt it was picked up
during quarantine and rabies already exists in the USA so just what “weird
diseases and parasites” are going to enter the USA that are not already there?
I am as passionate as anyone about the need to preserve
these dogs with an ancient heritage but to claim that the pariahs used to
establish the Canaan “breed” are only found in Israel shows a lack of knowledge
and is not supported by what facts we know. Yes they are a type with ancient
heritage but to say they are the oldest type in the world is unsubstantiated
and not true considering what we presently know of ancient types. Nor is it
accurate to say that these pariahs are becoming rare worldwide. Only some 15%
of the worlds dogs are pets and an almost insignificant percentage are pedigree
dogs. (Coppinger and Coppinger “What is
a dog”). The whole situation of dogs in the middle east and in other countries
is vastly different to that in the western world and this is something people
living in the USA or other “developed” countries unfortunately fail to
understand, as do many expat westerners living in the middle east who tend to
see homeless dogs through the limited experience they have in their home countries
where pariahs are not found.
If Canaan breeders genuinely want to preserve these dogs and
seek “to still bring in and preserve extant free living dogs and their
bloodlines” then it is high time they recognised that there are thousands of
these dogs out there. They also need to understand the true history of these
dogs, something that has far greater significance than the made up story aimed
at selling pups of pariahs, initially in Israel. As Myrna Shiboleth stated
recently in her open letter: “When I started with the Canaans, nobody in
Israel, other than my mentor, Prof. Rudolphina Menzel, and her few supporters,
considered them to be anything other than an Arab street dog and garbage dump
scavenger.” While dogs know nothing of human nationality, religious or cultural
divisions, that of course is precisely what these pariah dogs are. Myrna
herself knows that they are not officially “Israel’s national dog” yet
continues to claim this as do other breeders. I have no problem with any
country making them the countries national dog but to do so needs government
declaration which does not exist.
Calling the free living dogs outside of Israel as “baladi”
again shows somewhat lacking understanding. Baladi is a word used specifically
in Egypt and most closely translates to English as “folk”. It is used in Egypt
not only for dogs but to describe many other folk activities such as dancing
etc. ie, baladi dance, baladi songs and yes baladi dogs. If the unsupported
claim that that Canaan dogs were introduced to Israel by the followers of Moses
were true (facts show they were in the middle east before that time) would the
dogs in Israel not be baladi dogs?
It is shameful and disappointing to see claims of “knowledge
shared” when the knowledge being shared is extremely limited and inaccurate and
the approach to someone trying to learn at times extremely rude.
So yes indeed THINK and get your facts right and share
correct information not that dreamed up in order to sell dogs, before
condemning others.
There is still a golden opportunity to forget about
ridiculous kennel club closed book regulations and bring in more of these dogs
while concentrating on maintaining genetic diversity and eliminating all known
genetic health issues. How can this be done? Very simply by firstly recognising
the true distribution of these dogs then testing all current dogs for all known
genetic issues and not using any that are even carriers. This cannot be done
with closed breeds. It can be done with these dogs because there are still
thousands that could potentially be used. While rescue groups invariably neuter
dogs before homing them I don’t doubt they could be persuaded to help breeders
for the sake of ensuring the long term future of these dogs. Simply choose ones
breeders fancy and get their DNA checked for purity and health before adding
them to breeding stock and avoid any (probably rare) that carry any potential health
issue. Once no genetic health issues are present there is no need to test
offspring. No current established modern Euro-breed has such an opportunity. Do
I expect this to happen with Canaan dogs? No, not with the arrogant and often
ill-informed attitude of some people involved.
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