AKC- The confusion

[mjk05]

Assuming the measured 30% carrier rate accurately reflects the rate in the gene pool, with a simple recessive genetic defect you should be finding "affected" dogs with the genetic testing; unless most affected dogs die.

Only if "variant TNS" is survivable, which it probably isn't. But if TNS presents also as puppies who die before birth, perhaps even as embryos, or very shortly afterwards, then people aren't necessarily going to be seeing the classical "sickly 8 week old puppies" as often as we would expect.

 

Anyway, it's just a hypothesis. I just can't work out another explanation for affected pups not having been noticed before in a population with such a high carrier rate.

[Mark Billadeau]

Anyway, it's just a hypothesis. I just can't work out another explanation for affected pups not having been noticed before in a population with such a high carrier rate.

Another possibility is there are more genes at work here than the one(s) being tested for.

This might be examined with Carrier X Carrier beedings.

[mum24dog]

The fact that they're owned by people who do agility with them doesn't say anything about their ancestry, or the relevance of it to the current discussion.

 

Just adding background, that's all, but IMO it is relevant in that Chance has been diverted from the working dog community and the discussion has been largely about the need to test working dogs. Whether he was tested or not is unlikely to have any future impact on the breeding of working dogs.

 

As you say

 

Since almost the only people currently interested in testing for TNS are show/sports people, it makes sense that most of the pure ISDS-bred dogs identified as carriers are owned by those sorts of people.

 

But it's still a self selected sample and not necessarily statistically significant. Most sports participants don't breed their dogs (although it may feel like they do). The ones who do vary between those who do it just because they have a nice but not outstanding dog and who may or may not be interested in testing and those with a very successful dog who can charge £600-£700 for a pup or stud fee. Testing makes more sense for the latter type if only to try and avoid the pointing fingers if they don't and it goes pear shaped. Noone cares much if Joe Nobody makes a mistake.

 

I have no idea whether TNS is a problem in the working dog population in the UK/US/Aus/NZ etc but would tend to the view that if it were breeders would recognise a vested interest in testing. The fact that a few sport/show dogs have been shown to be carriers doesn't add much if anything to the sum of what we know, which is very little.

 

I sympathise with your view that it doesn't matter where it came from and that it should be nipped in the bud if possible. However, you are coming at it from personal experience which will colour your opinion.

I can also see the point of those who aren't prepared to throw money at what may be a negligible problem where they are without any evidence that it would be money well spent.

 

Purely hypothetically (and never going to happen), if I were thinking of breeding from my dog I would get all the tests going because that's what my market would expect. There is a current panic about TNS in the sport world and, like most of such net fuelled scares, I'm sure it is exaggerated. Soon it will be something else.

[jdarling]

Try:

Henniker Spyro

Wintertime Coast

Highfield Hazza Chance

How many generations of show champions are behind those dogs?

 

I don't know. Can you post the pedigrees? I don't have access to them, so it's hard to say. What was interesting is that three of the six I was able to find information on were merles.

[C Crocker]

<<<<<<<<<The ISDS certainly allow registration and use of prefixes. Wiston Cap? Bwlch Taff? Dewi Tweed? And in the UK, quite a lot of the obedience and agility people source their dogs from working breeders. As I understand it, they have the choice then to register the dog under an entirely different name with the KC, so many do. It doesn't mean the dogs are show-bred, you need to check out their pedigrees to determine that. Many of them have a single word ISDS name as well. I think some of pucksfurcoat's list are dogs from European countries where the same thing applies. >>>..

 

 

 

Just quoting part of your post that replied to my post. I believe I refered to the kennel name, which you refer to as the prefix as being the first part of a dog's name when registering them. I believe I also said I would want to see the pedigrees of these dogs with the fancy long names refered to in a previous post. I know about the "Bwlch" in Bwlch Taff, as I have a 7 year old ABC/ISDS reg bitch who was named after his first pup. I know about the Dewi part of Dewi Tweed , as I have a pup who is by a son of Millichap's Ben, Tweed's grand sire. I have an 11 yr old who came from Wales with the kennel name of Eryri. These kennel names are not the same as these five word flowing , rhyming type names of many of the dogs listed to have thrown TNS. Thus my thoughts that these dogs were not named these names as ISDS dogs, a may actually be more from show lines. Which of course is why I suggested it helpful to see the actual predigree and not just the name and reg number. I suppose it is possible that the pups were reg with the KC and ISDS clubs when they were born, and the owner gave them different names in each eg. That would account for the obvious KC sounding names of ISDS reg dogs? I dont know but I have yet to see any dog here in the USA show up at a USBCHA trial with name even remotely like "Red Spotted Loneliness of In and Out" referenced in the example post. The dogs at these trials are ABC/ISDS and or CBCA . Seems like two different worlds of dogs to mean, which at some point may have had some cross over if they changed ownership and the buyer went a different route with their new dog.

 

I feel for anyone having a pup with this TNS so I can certainly understand your concern. For my working Border Collies I do Optigen their eyes, and when they went to the USBCA Finals their eyes were checked there as well as having it done a few more times by a vet at home over the years. I did OFA hips /elobows before breeding, but other than that no other testing. If a disease/sydrome emerged within the dogs bred as mine I would certainly want to test for whatever that might be.

[mum24dog]

These kennel names are not the same as these five word flowing , rhyming type names of many of the dogs listed to have thrown TNS. Thus my thoughts that these dogs were not named these names as ISDS dogs, a may actually be more from show lines. Which of course is why I suggested it helpful to see the actual pedigree and not just the name and reg number. I suppose it is possible that the pups were reg with the KC and ISDS clubs when they were born, and the owner gave them different names in each eg. That would account for the obvious KC sounding names of ISDS reg dogs?

 

This is how you register ISDS dogs with the KC - with instructions on naming.

 

http://www.thekennelclub.org.uk/download/7448/Form-9.pdf

 

One example I can think of is Byanaway Will (ISDS) / Comebyanaway Will He Weave (KC)

[mum24dog]

What was interesting is that three of the six I was able to find information on were merles.

 

Chance is a donkey sized tri.

[pucksfurcoat]

TNS is a lethal disease. Dogs do not survive to reproduce.

[Liz P]

I've been trying to figure out a way to phrase this for days so as to not offend the pet owners, but I can't think of one.

 

If a puppy dies soon after birth, or is never born at all, leading to a slightly smaller than normal litter, you are out a few hundred dollars. It's a sad situation but also a fact of life. Sometimes young pups die and pregnancy isn't always smooth.

 

If you invest years into raising and training a dog that must be suddenly retired early because it has epilepsy, goes deaf or blind, you are out many thousands of hours of time investment and thousands of dollars. You also have to watch your working partner/buddy/right hand man go from vibrant working dog to disabled pet. It is a terrible disappointment.

[Mark Billadeau]

TNS is a lethal disease. Dogs do not survive to reproduce.

With a measured 30% carrier rate there should be a measurable number of dogs not surviving.

 

Assuming Hardy-Weinberg Equilibrium and a 30% carrier rate and using this Hardy-Weinberg Equilibrium Calculator an estimated 3.4% of the pups would have TNS. That is a high mortality rate to go unnoticed.

[pucksfurcoat]

I know some people who had TNS litters before the test, one who contributed greatly to the development of the genetic test. It is a heartbreaking experience - sometimes the pups live for a few months, ocassionally even longer, and they are very very sick.

[pucksfurcoat]

Hi Mark,

I think I missed something in this lengthy discussion - what is the rationale for using a 30% carrier rate? Thanks!

 

Sonja

[mum24dog]

To add to the naming info - a list of ISDS affixes

 

http://www.palado.demon.nl/bcdb/kennels.htm

[Mark Billadeau]

Hi Mark,

I think I missed something in this lengthy discussion - what is the rationale for using a 30% carrier rate? Thanks!

 

Sonja

The 30% comes from.......

Our local sheepdog population, as sampled so far (a reasonable proportion of dogs) apparently has a 30% rate of carriers.

[mum24dog]

To add to the naming info - a list of ISDS affixes

 

http://www.palado.demon.nl/bcdb/kennels.htm

 

But don't assume that you are looking at an ISDS dog if you come across one of those names.

 

Bryning for example turns out sport and show dogs with NZ blood, not working dogs.

 

A minefield doesn't go anywhere near describing this breeding business.

[Debbie Meier]

So, if a person here in the US owned a male that produced 4 litters out of 4 different females (two females maiden two bred in the past, one female had lost pups in the past), two litters everything was fine but two litters all but one pup died in, some dead at birth some dieing within 24 hours of birth would you suggest the TNS test on the male?

[Debbie Meier]

My thought is that TNS would not be the first plact to attribute the deaths, the death rate on the effected litters was higher then predicted on a carrier to carrier breeding.

[pucksfurcoat]

No right or wrong way to handle this issue, except to ignore it. Personally, I would look very carefully at the pedigree of both the Sire and Dams and compare to those of known TNS carriers, talk with the breeders of the Sire & Dams about related dogs regarding any similar issues, consult with a knowledgeable vet, gather as much information about the presentation of symptoms in the affected litters, consult with Alan Wilton regarding the symptoms if they suggest TNS, then make an educated decision about whether to test the Sire and/or Dams for TNS. The test is pretty reasonable. You can collect the sample yourself and submit, cost is about $85 USD.

Sonja

[brndlbc]

C Crocker wrote:

 

"As no one I have ever known to seriously breed cowhorses has included this strain of Quarter horse into their breeding program (Impressives are halter horses, generally not top working horses) , then for that reason they are not tested for hypp."

 

Taken from: http://www.ponycity.com/articles/health-care/hypp.html

 

"The produce of Impressive can now be seen in all disciplines of horses. Although his major impact has been on the Halter Horse industry, Impressive’s stamp of beauty, elegance size, muscling and athletic ability, have influenced everything from Pleasure Horses to Ropers."

 

I never thought Impressive was that great looking of a horse but regardless of my opinion, it didn't take too long for the effects of HYPP to spread out of the halter horses into other areas and to cause the AQHA to revamp their registration program. I suppose the same thing could potentially happen in the dog world should a single dog or line of dogs become "it" as Impressive did. Not an easy call at all. Great thread.

[Tea]

Hum that audame or whatever web site is interesting.(I joined it because I am very curious about this stuff.) However I am not sure I've figured it out.

It seems some dogs that are reg with ABCA, on there, are only reg with the AKC?? and they have no parents or ancestry.

I guess this happened with the dog war thing 10 years ago?

And there are some dogs that are not stock dogs that are clear for everything and tested for everything.

However there are some old time dogs that have percentages, odds, I guess if they are affected or carriers or what have you.

[Cynthia P]

Overall I am finding this thread very interesting. I did test for CEA (my bitch is a carrier) and one of the littermates was an affected, however he at 10 still has 100% use of his eyes. My other dogs have been tested or are clear by parentage

 

One of the other bitches and the affected dog were tested as well for TNS and CL ( both do AKC herding and agility) and were negative. I had not ever thought about testing my bitch for TNS as the lines were working bred dogs.

 

I can think of dogs that either, never take, have a litter of 1, resorb some puppies etc and if it were funded, it would be interesting to test North American dogs. But someone would have to show me that it truley is a problem.

 

Testing for genetic issues itself is not a red flag; It is responsible to check for things if there is a reasonable chance it can cause a problem. I'm not spending any extra money right now to test for TNS though.

 

Cynthia

[pucksfurcoat]

Got it!

So mjk05 - can you clarify that you meant a 30% TNS carrier rate for the tested working dog population in Oz, or for all tested Border Collies in Oz? Based on the results reported on the BC Health Site (incomplete data set as it is voluntary self reporting), roughly 20% of all tested dogs have been TNS carriers. I'm sure Alan Wilton could provide more accurate info. I agree - great thread.

Sonja

[pucksfurcoat]

Anadune allows and encourages individuals to enter Border Collies into the database, with no regard to their ancestry. They do populate it to a certain extent, but also rely on others, and they do verify information. For untested or unreported testing on dogs, they use the information available to calculate the probability of health status. Lots of good information is available - pedigree, health test results, color, test matings (including COI), etc. It is an amazing reference tool - kudos to Judit for developing it!

 

Sonja

[Tea]

I see, thank you for explaining

[mjk05]

So mjk05 - can you clarify that you meant a 30% TNS carrier rate for the tested working dog population in Oz, or for all tested Border Collies in Oz?

That's just in my state, I think. The vet who coordinates testing days here is in contact with the Uni of NSW, and put a brief report on it in one of our trialling association newsletters. I expect that there is a fair degree of sample bias, in that even within our state, the people most motivated to test have been those with known carrier lines. The last I heard Dr Wilton had suggested an overall carrier rate of 10% across all border collie types, but I would imagine it might be more like single digit figures if we really did widespread testing (that's based on nothing but my thoughts). The proportion of working dogs tested across the whole country is relatively low.

 

But I think it's worth thinking about our little population with its postulated 30% carrier rate, because some of the breeders involved have been using fairly tight inbreeding over 3 or 4 generations, and I would think that even with a lower carrier rate someone should have noticed something.

 

In your local sheepdog population, are you seeing stillbirths (without other obvious explanations like uterine inertia), or small litters?

 

Also, I wonder if you know of any breedings between two dogs that have been identified as carriers (other than your own one)? If so, what resulted from the breedings?

No, apparently not. I think I mentioned earlier that we had 3 dead pups from one litter of 8 a few years ago- one was a large pup, born first and dead; another was a small thin pup at birth, struggled from the start and died within a few hours; one was fine until a week old and then died suddenly (I think the bitch laid on her). But we knew the litter weren't TNS affected (the sire was tested clear). My husband had a litter from possible TNS lines about a decade ago where there were 8 or so pups and 2 stillborn/died shortly after birth. Certainly there have been some other occasional stillborn or weak pups, and small litters especially in the closely bred lines, but then that's one of the problems with inbreeding, isn't it? I think one breeder had a couple of pups die of gastro at about weaning time- the vet told him it was something they'd caught from the ducks.

 

Since the test became available, people have mostly been testing younger dogs for future breeding, rather than older dogs, and while some people with possibly carrier dogs aren't testing, I don't know of any other known carrier-carrier matings. I have heard that someone else bred a bitch who was subsequently found to be a carrier to a dog who was untested and lost a few pups at/shortly after birth, but that's just a rumour, no-one knows if that's TNS and further testing won't be done.

 

I agree with Mark that this could be explored more thoroughly by deliberate carrier-carrier matings, but it would take someone with way more intestinal fortitude than me to do it. There is a geneticist and dog breeder here (a former trialler) who did a lot of the work on the inheritence of cerebellar ataxia in kelpies, largely by doing test matings- but I don't know of anyone else who would be volunteering for TNS. And I assume you'd need some veterinary involvement, and from my experiences there isn't much interest now there's a test. It's assumed that if you think there could be an issue, you'll just DNA test and be done.

 

Someone else suggested to me recently that there could be other genes affecting TNS expression, and I guess that could definitely account for it.

 

Debbie:

So, if a person here in the US owned a male that produced 4 litters out of 4 different females (two females maiden two bred in the past, one female had lost pups in the past), two litters everything was fine but two litters all but one pup died in, some dead at birth some dieing within 24 hours of birth would you suggest the TNS test on the male?

Actually Debbie, I wouldn't be thinking TNS as a first differential there- although it's certainly possible, the chances of two entire litters, especially large litters, all having TNS is relatively low. Personally (and I'm not a vet or even an experienced dog breeder) I would be thinking more of infectious causes first. But it wouldn't hurt to have TNS somewhere down the list as a possibility, and testing for it wouldn't do any harm if you wanted to (just don't tell anyone that you did ).