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[LEOLIST] Is there evidence of Inbreeding Depression in Leonbergers?
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Karen Hindson
to LEOLIST
Follow up message
Hello to all the "statistical boffins" out there.
Many pure bred dogs are in dire straits owing largely to inbred populations and lack of genetic diversity which in a nutshell, boils down to Inbreeding Depression.
Normally natural selection would deselect harmful genes but human intervention and the promotion of the "matador sires" and so called "line breeding" in the never ending attempt to breed the ultimate show winner, has seen many breeds change extraordinarily, not only in conformation but also sadly in many detrimental health issues and therefore overall longevity.
I believe that there is evidence of inbreeding depression in Leonbergers and I would like to know how one could set about an analysis of all the information we have to hand to either confirm or disprove this belief.
My reasons are:
a) Overall longevity is decreasing at an alarming rate. Although it would appear that the Leos of yester year with what looks like incredibly high COIs (relatively speaking) actually had a multitude of unknown ancestors, i.e., ancestors without registrations. Ancestors that may or may not have been Leonbergers at all. Nevertheless, that meant diversity!
b) There is clear evidence that Osteosarcoma and Hemangiosarcoma are the 2 main cancers that afflict the Leo. Is this due to inbreeding depression? How much does environment, diet, etc. play a part?
c) Inherited Leonberger Polyneuropathy. Big question mark here, relatively small problem...we think! But where does it fit in?
d) Other assorted health issues: Increasing evidence of heart, eye, thyroid, allergies and other autoimmune troubles, even elbows are becoming a problem!
Unfortunately, as breeders are accustomed to see their dogs as they are, their morbidity and short life span is "normal" to them, and the counter proof cannot be shown to them within their breed, they will only accept it if their breed is already quite
excessively down so that no effective outbreeding within the breed will
be possible any more...once a single gene is lost, it can never be regained, no matter how hard one tries to outcross.
There is a telling argument by Jonathon Smid in his paper that shows statistical
analysis of a co-relation between rise of COI and rise of cancer rates:- "Increased mortality in Rhodesian Ridgebacks: the consequences of inbreeding depression". (U
Ottawa, 2001) http://www.andycheah.com/files/RRLongevity.pdf.
So, if anybody has any ideas to how we can subjectively look at how inbreeding depression may be affecting Leos, speak now! -:)) And, please don't quote Malcom Willis who only looks at 5 generation pedigrees and says that there is no inbreeding depression in any pure breed!
Karen
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-
Subject: RE: [LEOLIST] Is there evidence of Inbreeding Depression in
Leonbergers?
You would have to definitely set up a control and experimental group.
Though I don't think many of us would intentionally loan our leos to that
other than just health surveys. There are just as many diseases in the
mixed breeds but many of those findings aren't reported like a club would
for the breed. I had never thought about it until the other day I was
taking my girl for a health check. A wonderful lady with a mix was in the
vet. Her dog had a brain tumor(mixed breed). She said the one before(mixed
breed) had also had cancer. She adopted it with the existing condition. So
it is so hard to definitely say. I know there are many who breed for
confirmation but there are those who breed for health too. Maybe a vet or
technician could respond and let us know if they see just as many cancers in
the mixes as well? Surveys and test would have to be taken worldwide not
just the US to come to a definite conclusion.
Maybe we will have clear answers soon.
Shelia - Show quoted text -
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> You would have to definitely set up a control and experimental group.
Absolutely! Therefore I need a "boffin" who can analyse the huge amount of info we have on ileo
>I had never thought about it until the other day I was
> taking my girl for a health check. A wonderful lady with a mix was in the
> vet. Her dog had a brain tumor(mixed breed). She said the one before(mixed
> breed) had also had cancer.
Well this is the "bug" that bothers me also. The trouble is that no studies can be undertaken on cross breeds because there are no pedigrees to study. A "mutt" may just as well be inbred as a Leonberger that has a pedigree that can be traced back to 1912! I have two moggie cats (actually, sadly I just put one to sleep) who are nearly 16. Their father was their grand father was their great grand father! They are moggies but all the same inbred to bug****!
However, in general terms, it is pretty much accepted that cross breds live longer and therefore have less health issues.
The Leonberger has an incredibly small gene pool as it is. Should we not be looking to increase unique ancestors?
- Show quoted text -
Karen
_________________________________________________________________
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I think that comparing cross bred or "mutts" to a 'pure bred" isn't as easy as most people think...first of all...many of the mutts are actually inbred...too many people that had gotten a couple of free dogs from some mis-hap random breeding of another person that had kept a son from their previous accidental breeding and then it happens again...a large portion of the mutts are actually just as much, if not more so inbred than a purebred dog...and as far as the health issues and what not...there is no record of any sort on the random accidental breedings of mutts so there is nothing to compare it to...and being in an all breed rescue you see many heart problems, hip problems, allergies, eyes, thyroid...all kinds of things...there are Vets in our area that work closely with rescue groups and treat the dogs that come in that would have a wealth of information on the mixed breeds and the problems they suffer...
if you are thinking of taking a GP and breeding it to a Leo for instance...won't guarantee you a better outcome just because you are out crossing so to speak...the 2 dogs be it purebred or mutt...will bring good genes and bad genes...
even the leonberger data bases are not covering all of the Leos in the world...nor covering the offspring and health issues...I know here in the states there are hundreds of Leos (if not thousands) that are not in any of the data bases...and that is just one country...I am not sure there is a way to really get a clear picture of the Leos health issues when we are only able to collect info on a small portion of the Leonbergers...for every one Leo that is reported I bet there is at least 2 others out there that are not...and are those other 2 good health or bad health...old or young...no way of telling....
Kat ----- Original Message ----- From: "Karen Hindson" <karenhindson@HOTMAIL.COM>
To: <LEOLIST@APPLE.EASE.LSOFT.COM>
Sent: Monday, June 01, 2009 8:55 AM
Subject: Re: [LEOLIST] Is there evidence of Inbreeding Depression in Leonbergers?
- Show quoted text -
However, in general terms, it is pretty much accepted that cross breds live longer and therefore have less health issues.
The Leonberger has an incredibly small gene pool as it is. Should we not be looking to increase unique ancestors?
Karen
Reply
Jun 1 (3 days ago)
Maija Kalnberza
to Karen
Follow up message
Hello!
Congratulation! You stressing a very important point in Leonbereger breeding system. I am 100% agree with you! I was thinking about the same things a lot too. And I allready wrought letter to President of Leonberger Union - Mr. Willi Güllix (Germany) . Here it is:
Dear Sir,
Latvian Leonberger Club is among the youngest one in the World. We start our work with research about most well known kennels and made a contact with a people who are really enthusiastic in this field, as, in fact, we are.
First decision we made was - we should bring to our Country only dogs who is healthy and who could be a start point for selective work to make our own Leonberger line.
During one year we brought to Latvia more then 10 puppy from different part of the World, because we want to avoid inbrindig. These puppy was a best ones from the litters we choose. And, after about 2 years we found out that 25- 30% of our dogs have different genetic desiseas but one dog have a minor problem, which is allowed to exist,but, having this problem this dog will never ever become in a top position, and we could not use him in breeding program.
Off course when we get the these sad news about this genetic problems, first was to call breeders and kennels where from we get these dogs, and the common answer was -.." you could put your dogs through, more or less big, cosmetic surgery. Our people always do that!" That was shock and surprise in one! So now for some it is not dog competition , but surgeon competition!
Our club is very young, and we have not very much dogs in our region, but we already want to disagree with that!
Breeders of winning dogs earn the respect of their peers and others, and that respect can lead to enhanced benefits to the breeders. Within this environment, other benefits can also be accrued from breeding winning dogs. These include improving the breed; gaining personal satisfaction; and commanding higher prices for puppies bred from the winners bloodlines.
Since genetic diseases are passed to subsequent generations by parents who contribute the causal factors contained within their own genetic makeup, one point regarding this problem is fundamental:
The elimination of genetic diseases can only be accomplished through selective breeding
The problems lie in determining how to identify the diseases' causal factors in dogs; in understanding when not to breed them; and in the implementation of selective breeding programs based upon these factors. Some of the avenues to be investigated include:
Basic Education
First and foremost in solving any problem is ensuring that everyone involved understands it.
the basic information required to make progress toward the elimination of genetic disease by developing an effective breeding program is within the reach and understanding of everyone concerned.
Breeders should understand the implications of genetic diseases recognized as affecting their breeds, and take steps to breed only those dogs that will minimize the propagation of unwanted characteristics.
Cooperation between dog breeders, researchers, prospective purchasers, and purebred dog organizations at all levels is essential if genetically healthy dogs are to become a reality.
One thing is certain - without the continued attention of many people, the situation can only get worse.
May be it is time to think how to make situation impossible for not very clean breeders and veterinarians to destroy such a beautiful breed as LEONBERGER is!
Best regards,
Dr.Med.Maija Kalnberza-Brante
President of Latvian Leonberger Club.
www.leonbergerdog.lv - Show quoted text -
On Mon, Jun 1, 2009 at 2:53 PM, Karen Hindson <karenhindson@hotmail
.com> wrote:
Hello to all the "statistical boffins" out there.
Many pure bred dogs are in dire straits owing largely to inbred populations and lack of genetic diversity which in a nutshell, boils down to Inbreeding Depression.
Normally natural selection would deselect harmful genes but human intervention and the promotion of the "matador sires" and so called "line breeding" in the never ending attempt to breed the ultimate show winner, has seen many breeds change extraordinarily, not only in conformation but also sadly in many detrimental health issues and therefore overall longevity.
I believe that there is evidence of inbreeding depression in Leonbergers and I would like to know how one could set about an analysis of all the information we have to hand to either confirm or disprove this belief.
My reasons are:
a) Overall longevity is decreasing at an alarming rate. Although it would appear that the Leos of yester year with what looks like incredibly high COIs (relatively speaking) actually had a multitude of unknown ancestors, i.e., ancestors without registrations. Ancestors that may or may not have been Leonbergers at all. Nevertheless, that meant diversity!
b) There is clear evidence that Osteosarcoma and Hemangiosarcoma are the 2 main cancers that afflict the Leo. Is this due to inbreeding depression? How much does environment, diet, etc. play a part?
c) Inherited Leonberger Polyneuropathy. Big question mark here, relatively small problem...we think! But where does it fit in?
d) Other assorted health issues: Increasing evidence of heart, eye, thyroid, allergies and other autoimmune troubles, even elbows are becoming a problem!
Unfortunately, as breeders are accustomed to see their dogs as they are, their morbidity and short life span is "normal" to them, and the counter proof cannot be shown to them within their breed, they will only accept it if their breed is already quite
excessively down so that no effective outbreeding within the breed will
be possible any more...once a single gene is lost, it can never be regained, no matter how hard one tries to outcross.
There is a telling argument by Jonathon Smid in his paper that shows statistical
analysis of a co-relation between rise of COI and rise of cancer rates:- "Increased mortality in Rhodesian Ridgebacks: the consequences of inbreeding depression". (U
Ottawa, 2001) http://www.andycheah.com/files/RRLongevity.pdf.
So, if anybody has any ideas to how we can subjectively look at how inbreeding depression may be affecting Leos, speak now! -:)) And, please don't quote Malcom Willis who only looks at 5 generation pedigrees and says that there is no inbreeding depression in any pure breed!
Karen
_________________________________________________________________
Kat wrote:
>many of the mutts are actually inbred.
Yes, could be as in the example of my moggie cats.
But you diverge from basic question in much of the rest of your post, albeit
you have adressed the growing problem of non registered Leos. Ileo attempts
in a small way to list these Leos also but the bottom line comes down to
what we know and how best this information should be put to the welfare and
future of the Leonberger Karen
Reply
Karen Hindson
Hey, Sandy! Long time no hear -:)) Hmmmm, if you have the answers and have al...
Reply
Follow up message
Hey, Sandy!
Long time no hear -:))
Hmmmm, if you have the answers and have already solved the problems that
defeat the rest of us mere mortals (well renowned geneticists included)
could you be a little more specific in terms of your scientific background?
I don't see how I neglected the problems when one solely outcrosses in the
Leonberger, since in fact, this is a total impossibility in the first place!
My question remains: Is there inbreeding depression and how to find the
answer
Karen
http://hochspitzmountaindogs.net
http://ileodata.com
http://leosvictoria.org
From: shreuter@gmail.com
To: karenhindson@hotmail.com
any good biologist can figure this out. I know I have done it along with
several other research scientist in other scientific fields with the data
that i have for the last 17 years. Obviously you are neglecting the
problem that pops out when one solely does outcrosses and unfortunately
learns that the two they have combined are carriers for a genetic
problem
_________________________________________________________________
Looking to move somewhere new this winter? Let ninemsn property help
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K. Wilson
Yes, YOUR info may be on there...but not all Leos are... And Karen my concern...
Jun 1 (3 days ago)
K. WilsonLoading...
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K. Wilson
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Yes, YOUR info may be on there...but not all Leos are...
And Karen my concern is that as great as the databases are and how useful they can be...I am not convinced that this info offered is actually really reflecting a true representation of the health of the Leos...and if you are using only the info that "we" have access to...one might come to a conclusion that the health of the "average' Leo...or at least the average on the database is this and that...when actually...if all those other non represented Leos were some how put in the equation...we would see things differently...???? and if we 'read' too much into the limited information we have that we could actually do the breed more harm rather than good...????
the databases are great...I just wish that there was more participation...but we do not live in a perfect world...
----- Original Message ----- From: "montrond" <montrond@COX.NET>
To: <LEOLIST@APPLE.EASE.LSOFT.COM>
Sent: Monday, June 01, 2009 12:17 PM
Subject: Re: [LEOLIST] Is there evidence of Inbreeding Depression in Leonbergers?
My info is registered with Worldwide independent leonberger database. It
can be gathered from that.
-----Original Message-----
From: Mailing List for Leonberger Fanciers
[mailto:LEOLIST@APPLE.EASE.LSOFT.COM] On Behalf Of Karen Hindson
Sent: Monday, June 01, 2009 11:44 AM
To: LEOLIST@APPLE.EASE.LSOFT.COM
Subject: Re: [LEOLIST] Is there evidence of Inbreeding Depression in
Leonbergers?
Kat wrote:
many of the mutts are actually inbred.
Yes, could be as in the example of my moggie cats.
But you diverge from basic question in much of the rest of your post, albeit
you have adressed the growing problem of non registered Leos. Ileo attempts
in a small way to list these Leos also but the bottom line comes down to
what we know and how best this information should be put to the welfare and
future of the Leonberger
Karen
http://hochspitzmountaindogs.net http://ileodata.com http://leosvictoria.org - Show quoted text -
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Jean Boggie
I know that I have been very aware of the decreasing life span and increase i...
Jun 1 (3 days ago)
Jean BoggieLoading...
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Jean Boggie
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I know that I have been very aware of the decreasing life span and increase in health issues not just cancers but also heart problems including cardiomyopathy (which is not discussed), fertility especially monochordism, polyneuropathy, eye problems (cataracts), etc. At present I have one Leonberger who is 11 1/2 years old (Quintillius Varus Lowe v. Esing, and one Leonberger who is 10 years old Ch Kallistra von der Lowenhole. I have two of Kallie's children from her A litter - Glitz and Flip - and one grandchild - Ryker. However we have lost four puppies from that same A litter - two to cancer and two to undetermined causes. I have my suspicions on the causes for the two unexplained deaths. Following the second unexplained death, I have tried to breed away from the lines in my dogs.
There is an ignorance of how prevalent some problems have been becoming. No breeder wants to be labelled as the producer of a particular health problem so most are reluctant to disclose these problems. Many of these problems are caused by recessove gemes. The problem only occurs if you breed a particular stud and bitch together. If you bred to a brother and/or sister of either, you would not produce the problem. This is part of why breeders check ancestory of whomever they are breeding to. It is unfair to label a breeder as the cause of a particular problem unless they have bred more than one litter with that problem after the problem was discovered. You cannot forget that some health issues do not appear until a dog is in the two to five year old range (i.e. hypothyrodism).
For example polyneuropathy which has been recognized as a big problem for years here in the USA is finally being diagnosed, discussed and researched in Europe. For many years European breeders did not know of the disease and/or refused to acknowledege its existence. This includes well known Leonberger kennels. I spoke to one kennel which has produce well over twenty champions who perfectly described a dog with laryngeal paralysis (LP) as well as polyneuropothy symptoms but had no knowledge of the fact this was a disease. They had at least three litters on the ground from one dog with those symptoms. I put them in touch with our US group. Europe is now wholeheartedly behind research into this problem and has a very wide base of Leos which includes the ancestors and other relations of our Leos to do research on.
The big thing here is how open everyone is to exchanging the information. It is great to say that all breeders should make information on their litters available and that everyone should have access to all the health information on Leos but knowing human nature, I strongly belief that a nonbreeder Leo person might well label a kennel as producting unhealthy dogs with this or that health problem where it might only be only one litter and/or dog that has the problem. You and I both know that people are reluctant to purchase puppies from someone produces dogs with health problems. This is why an open as opposed to a closed only available to breeders health registry is such an issue.
Responsible breeders make their breeding decisions based on the health information available to them. If problems are not disclosed then you only learn about their existence after the fact. Many breeders are reluctant to supply negative information. Also I have found that sometimes it is hard to get negative health information from the breeders of my dogs because they have not received the information from the breeders of their dogs. In addition most breeders have a hard time getting information on the puppies from all of our puppy owners. There are those owners who stay in close touch or in touch at least once annually or if anything happens, however, there are also owners who take the puppy, walk out the door and despite their promises and even contract provisions never contact the breeder again. Breeders like to see what they produced and to hear about the health of those dogs. This is how we can really see what we are producing and can track any health problems in our lines.
Jean
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montrond
A huge help would be for those who get a puppy to do so from people who do te...
Jun 1 (3 days ago)
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montrond
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A huge help would be for those who get a puppy to do so from people who do
test and study pedigrees. It would help to phase those who don't out of
practice to a degree. I am sure if I bred long enough there will be some
problems crop up as in all lines.
-----Original Message-----
From: Mailing List for Leonberger Fanciers
[mailto:LEOLIST@APPLE.EASE.LSOFT.COM] On Behalf Of Karen Hindson
Sent: Monday, June 01, 2009 12:19 PM
To: LEOLIST@APPLE.EASE.LSOFT.COM
- Show quoted text -
Subject: Re: [LEOLIST] Is there evidence of Inbreeding Depression in
Leonbergers?
Hey, Sandy!
Long time no hear -:))
Hmmmm, if you have the answers and have already solved the problems that
defeat the rest of us mere mortals (well renowned geneticists included)
could you be a little more specific in terms of your scientific background?
I don't see how I neglected the problems when one solely outcrosses in the
Leonberger, since in fact, this is a total impossibility in the first place!
My question remains: Is there inbreeding depression and how to find the
answer
Karen
http://hochspitzmountaindogs.net http://ileodata.com http://leosvictoria.org Date: Mon, 1 Jun 2009 11:46:09 -0400
Subject: Re: [LEOLIST] Is there evidence of Inbreeding Depression in
Leonbergers?
From: shreuter@gmail.com
To: karenhindson@hotmail.com
any good biologist can figure this out. I know I have done it along with
several other research scientist in other scientific fields with the data
that i have for the last 17 years. Obviously you are neglecting the
problem that pops out when one solely does outcrosses and unfortunately
learns that the two they have combined are carriers for a genetic
problem
_________________________________________________________________
Looking to move somewhere new this winter? Let ninemsn property help
http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fninemsn%2Edomain%2Ecom%2Eau% 2F%3Fs%5Fcid%3DFDMedia%3ANineMSN%5FHotmail%5FTagline&_t=774152450&_r=Domain_
tagline&_m=EXT
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Knut J Bjuland
There are a loot of information about inbreed mice contra out breed mice. Inb...
Jun 2 (2 days ago)
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Knut J Bjuland
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There are a loot of information about inbreed mice contra out breed mice. Inbreedmice often lives about 500 days while out breed mice may life as long as 700 days. These data comes from laboratory mice, where the inbreed mice are breed with full brother-sister mating for 20 generation or more. Inbreed breed tend to accumulate recessive mutant that may often be the cause of disease. When you are doing a out breeding with an inbreed breed the new mate tend to become mote health because some recessive mutation is hidden away by dominant health genes. I do not know of any screening which is done international, but the pet insurance companies may have a lot of data about different disease in different breed among them mix breed versus pure breed.
I think the society should conduct world view survey for cancer in dog because it might also uncover things that may be dangerous to human as well. Since the dog develop cancer much faster than human they might give us information about new substance which is may cause cancer much early than if only humans are measured. Since cancer is more prevalent in some dog breed due to that many dogs in some breeds carries genes which cause cancer. You can do search in pubmed,http://www.ncbi.nlm.nih.gov/pubmed/ to get an idea, since it give only search peer review article in both human and veterinary medicine . --
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Karen Hindson
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Shelia wrote:
>
> At what point is there a considered out cross? After several generations
> isn't it considered line breeding at a small percent. Can you totally
> outcross anything anymore? Just wondering
Many breeders will look at a 5 generation pedigree and if that pedigree has no duplicated ancestors, i.e., and AVK of 100%, the breeding will be considered "outcrossed" even though it maybe that there are several duplications happening in the 6th generation.
Many breeders take the view that they are "linebreeding" when they choose just one or two ancestors to appear more than once in the five generation pedigree and only consider "inbreeding" as being between very close relatives; father/daughter, brother/sister, etc.
This is of course nonsense, there is NO difference between line and inbreeding.
It is not possible to totally out cross any pure breed anymore unless another breed(s) is introduced and then you have a "mutt", not a pure breed, so most canine genetecists agree that inbreeding depression starts happening at COI 4% at 10 generations. Even Malcom Willis agrees on this point except that he looks only at 4 or 5 generations which is really stupid -:))
In breeds where the total population is still very small and number of unique ancestors miniscule as is the case with the Leonberger, the consensus amoungst geneticists is for breeders to try to aim for between 5%-6% at 10 generations and over several generations under 4%. Overall COIs 30 generations and beyond will never decrease because the pedigrees will always go back to the same founding dogs.
Sadly very few Leonberger pedigrees are managing a COI of 5% but some ARE, so that means it IS possible. We even have a few litters that have LESS than 4%!!!
In my opinion, breeders need to be focusing on 10 generation pedigrees and NOT 5 and also need to have a comprehension of how Relationship Co-efficients work which would be one of the ways we could help pin-point carriers of recessive genes.
It is a long term project and one that would need co-operation from all countries to be able to make a significant head start.
All breeders should make an effort to understand at least the basics of how genetics work and clubs, (Germany, Switzerland spring to mind) instead of making strict rules in terms of what can or can't be bred from dogs' hip results and show results, thus limiting the gene pool even further and promoting the matador sires, should be insisting on limiting COIs to 10 generations.
Over the last 30-50 years the Leonberger has lost an awful lot "lines" thanks largely to the rules of the German club which I am sure were intended to improve the breed but which in fact has lead to severe loss of genetic diversity.
Karen
http://hochspitzmountaindogs.net
http://ileodata.com
http://leosvictoria.org