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HYPP N/H - Now what?

Horse Care
#21

Ok, I’ll buy that :slight_smile:

It’s pretty well established that horses that are linebred to Impressive have a greater likelihood of being either H/H or N/H than those with a very limited amount of Impressive on their papers. Of course, ANY horse that goes back to Impressive runs a risk.

If the parents are N/N, it doesn’t matter how linebred the horse is to Impressive - he won’t get it. Unless we get another spontaneous mutation :slight_smile:
If the parents are NN and NH, then there is a 50% chance of the horse being NH, regardless of how linebred to Impressive he is, or not, and so on. Any horse going back to Impressive has a risk, unless both parents are NN.

#22

[QUOTE=JB;3194992]
If the parents are NN and NH, then there is a 50% chance of the horse being NH, regardless of how linebred to Impressive he is, or not, and so on. Any horse going back to Impressive has a risk, unless both parents are NN.[/QUOTE]

This is correct. But what I’m trying to say is that when you have a horse with Impressive on both the sire and dam side AND THE HYPP STATUS OF BOTH PARENTS IS UNKNOWN you run a greater risk of getting a horse that is N/H or even possble H/H. It’s a gamble I wouldn’t be willing to take, no matter how nice the parents might be. It is only very recently that registration papers have provided HYPP status.

Straight from the oracle (the UC Davis website):

Inheritance and Transmission of HYPP
HYPP is inherited as an autosomal dominant trait, which means it can occur in both males and females and only one copy of the gene is required to produce the disease. The trait is inherited from generation to generation with equal frequency; it does not get “diluted” out or skip generations. Breeding an affected heterozygous horse (N/H) to an affected heterozygous horse (N/H) will result in approximately 50% carrying the defective gene (N/H), approximately 25% will be normal (N/N) and approximately 25% will be homozygous carriers (H/H). Breeding an affected heterozygous horse (N/H) to a normal horse (N/N) will result in approximately 50% normal offspring and approximately 50% carrying the defective gene (N/H).

#23

I have a call into my vet to discuss diet. He is on a sweet feed - but it is not high in molasses and the potassium percentage is under 1%. My problem is my hay. He is on timothy - but due to space constraints I buy retail every other week - and they are not consistent with the batches, so testing is out. The grazing is nonexistant in the paddock, and I have another older guy to worry about.

There were several reasons his papers did not come with him - most of which was because of his idiot prior owner and the situation. I do know some limited info about him and know he did the race track pony thing for a while. He is actually an extremely good looking gelding and I think that was a tip off to the vet. Between that and noises he makes when eating, she was suspicious.

Should I worry about using medication? I ship this horse occasionally (he is a good shipper) to my trainer’s for brush up lessons.

#24

All three of my horses have been QHs. Had two N/N Impressive-bred horses that fit the above description. Both fared better on an EPSM type diet and lots of turnout… they had weird, twitchy, metabolic, muscle stuff going on. We even treated the mare for EPM at one point because the vets were stumped by her symptoms.

#25

Well why didn’t you say so in the first place :wink:

#26

Just to clarify AQHA is not registering H/H foals born in 2007 and beyond They are not pulling the papers on horses that are H/H and born prior to 2007.

Rule from AQHA rule book:

“3) Effective with foals born on or after January 1, 2007,
all descendants of the stallion Impressive, AQHA registration number
0767246, shall be required to be parentage verified and HYPP
tested, subject to the conditions in ©(2) above. Any foal testing
homozygous positive for HYPP (H/H) will not be eligible for registration
with AQHA.”

They are not pulling the papers of previously registered horses that are H/H and have not stopped registering N/H horses yet so the absense of papers on this horse doesn’t really mean that it was not eligible for registration.

#27

[QUOTE=JB;3194660]
Nope. It IS a disease and ANY N/H horse can have symptoms, ranging from “what’s that twitch in his flank?” to the horse thrashing around on the ground. Having a disease does not necessarily mean the horse will or will not be symptomatic - depends on the disease. Not having symptoms doesn’t mean a disease is not present.

It is likely a genetic defect that became perpetuated. I have never heard of it being from too much line/inbreeding.

Color has nothing to do with it. The disease, especially the H/H form, can indeed cause that heavy halter-body look, but there are just as many light types that are either H/H or N/H.

Registration is restricted to N/H and N/N horses. No H/H horses anymore. N/H horses are hopefully being disallowed soon. If I were to buy a horse of unknown breeding, or that was known to contain any QH or Paint blood, I would have him tested. Looks need to be left out, as a lean TB-looking QH can be HH or NH.[/QUOTE]

Genetic defects ARE often perpetuated by line/inbreeding. Otherwise they remain spontaneous mutations and they are not passed on. But if a horse has a spontaneous mutation of one allele and is bred to its offspring then the mutation becomes more prevelant. And I do not think that anyone is saying that a sorrel with high whites is H/H or N/H because they are sorrel or has high whites but that many Impressive offspring have these characteristics as well bc that is common for Impressive offspring. I do agree that phenotype is not a good indicator of H/H or N/H or N/N.

#28

No, they aren’t passed on if that mutated horse is never bred, or if the only times s/he is bred it isn’t passed on. They ARE passed on, regardless of line/inbreeding, if the horse is bred and passes it on. The only thing line/inbreeding does is increase the changes of producing a homozygous horse who WILL pass that on. I think at some point it stops being called linebreeding even, so breeding a N/H to an N/H where Impressive is 10 generations back, nothing else in common, isn’t really linebreeding anymore.

But if a horse has a spontaneous mutation of one allele and is bred to its offspring then the mutation becomes more prevelant.

Only if the mutation is passed on. Otherwise it dies out. There are TONS of Impressive lines that don’t have HYPP.

And I do not think that anyone is saying that a sorrel with high whites is H/H or N/H because they are sorrel or has high whites but that many Impressive offspring have these characteristics as well bc that is common for Impressive offspring. I do agree that phenotype is not a good indicator of H/H or N/H or N/N.

I believe I have seen more plain-colored Impressive offspring (not necessarily direct sons/dtrs) than the chrome-y ones. I’ve seen lots of non-halter-y offspring too that are at least N/H. Maybe his 1st and 2nd generation (even 3rd) were very type-y, but they have long since moved past that. There are lots of chestnut/high whites halter-y looking horses that aren’t related to Impressive at all. So you are right, phenotype is absolutely not to be taken as proving anything about the existence of HYPP.

#29

JB - I think we generally agree. Yes, the only way to pass on mutations is to breed the animal.

Sorry to the OP - we have totally high jacked your thread but I love this discussion. I hope all is well with your new boy! Keep us updated!

#30

[QUOTE=findeight;3194378]

Traced to Impressive it is likely the result of too many crosses to too many relatives. Seems more prevelent in those with heavier bodies but a refined head, neck and throatlatch, lots of high white, a bright coat color-usually chestnut but all the others too. In other words, the perfect QH show horse.[/QUOTE]

That is my N/H horse to a “T” No symptoms not ever not even when he was on his way to hs Superior halter title at his heaviest and most conditioned. You can not generalize about coat and markings and head type - if were just that easy And too any crosses - that is a silly statement. Impressive himself was just a generation in places from a TB!

[QUOTE=findeight;3194378]
Since AQHA restricts registration…I would be suspicious of no papers on a horse that looks like these do. I would even be suspicious of those with papers that look like this but don’t seem to trace to Impressive-people lie when money is involved.[/QUOTE]

Umm - We have had MANDATORY genetic testing for stallions and broodmares for 15+ years, and resulting foals for over a decade - can’t fake genetics no matter how much denero is involved. IF you buy without papers you take your chances. If you are buying without a PPE you are asking for trouble on ANY purchase!

[QUOTE=findeight;3194378]
Finally, not all Impressive decendents carry it and he was otherwise a fine horse and has many fine decendents on the ground. I’d buy one but not without the test…and I’d test anything that looked like that even if the papers said otherwise.[/QUOTE] I bought one willingly and KNOWING he was N/H. At 8 w/o an episode he statistically will be just fine.

STATISTICALLY MOST N/H horses are just fine. And MOST only require special care if they have EVER had an episode. Otherwise it is an ounce of pervention.

Clearly there is far more testing needed to define the variations in N/H!

To the OP - Switch to Safe Choice & drop the Sweet feed. If he has no symptoms keep a ready eye but do not lose sleep over it. I ship/haul/ride my horse all the time. He is now an “A” hunter - no worries not ever!

#31

Well I spoke with the vet last evening. Needless to say she was not overly surprised since she suggested it in the first place. Our game plan for now is “if it ain’t broke don’t fix it”. By that I mean we are not going to tinker with his feed. He is on a sweet feed as I indicated earlier - however it is not high in molasses and the potassium is .9%. We will keep him on the timothy hay. No alfalfa. She is ordering me the meds as a preventitive to use during high stress times (i.e. long shipping trips, etc) and to have on hand should he have any problems. She also shared that she usually does not have problems in her practice with the N/H horses - it is the H/H horses that experience the greatest problems. I know she was trying to alleviate my concerns. If nothing else, I guess he resale value just bottomed out as I would disclose this should I ever decide to sell.

He is a flashy palomino with high whites and a white face. Muscular build. Yet I know of another Impressive that looks like a TB - gray, tall, rangy. He does experience episodes, which is why I am somewhat apprehensive here.

For the QH people - now that I know this, is there anyway that I could determine who my guy actually is? Is there DNA testing that could tell us his identity? I have always wondered who is really is and did not know if there was any process with the AQHA to help with his identification.

#32

Sounds like a likely suspect with his color…the grey also because he is confirmed as a descendent. Not all Impressives are flashy but the flashy, heavy bodied but refined ones do seem to go to him more often then not. He put quite a stamp on his offspring physically.

Far as the DNA thing…believe you would need samples from parents as well to determine parentage. They may keep test results but likely would not search them like a crime lab looking for possible matches for unknown animals-if they did it would be $$$$$.
Can suggest tracking down where the horse was before last owner had him and trying to discover the breeder. You can track them sometimes that way…try to find a registered name to start.

For resale, he may be able to get in with the Palomino folks. There used to be 2 different registries for them, they run shows and all that. It would cost as a hardship but, as a gelding, he may still be eligible. Also depend on the clarity and tone of his color and you’d probably need an inpsector to physically assess him.

But it would increase his resale and create a market.

#33

ANY horse who is known to be Impressive bred but whose parents’ status is not known is suspect until proven otherwise. It doesn’t have to be the flashy red-based horses. Now maybe that’s what you really mean, but you make it sound like all flashy red-based horses who are heavy in build are immediately suspected to carry HYPP until proven otherwise. That leads people to believe that the black-based horses without chrome and who are more TB-looking in build are not suspect. Impressive is so far back in most horses today that color and looks have little to do with it. That’s the point that needs to be made.

[quoteHe put quite a stamp on his offspring physically.
[/quote]

Yes, in the beginning, but he’s so far back now in most lines that he doesn’t have a lot to do with the build of a horse anymore. And, there are heavy lines that have nothing to do with Impressive because that’s the look people were emulating and either breeding for it or feeding for it.

#34

Well, I thought that was the point I made…and don’t know if you have been active buying and selling lately but many buyers are suspicious of the build and flash and want the proof of N/N. Likewise want it with ANY horse with Impressive.

But then there’s the big QH farm up the road where the guy concentrates his breeding on Impressive and says you can’t win at Halter with an N/N…backing that up with a trailer full of tricolors from Congress and all these statues from the Worlds-and high prices for numerous yearlings that look just like the first generation. I wouldn’t be so sure the body type and color are too far make to have any influence. Wouldn’t be real sure some hanky panky didn’t go on in years past with some descendents credited to other stallions of similar appearance either.

#35

[QUOTE=JB;3194992}

If the parents are N/N, it doesn’t matter how linebred the horse is to Impressive - he won’t get it. Unless we get another spontaneous mutation :slight_smile:
If the parents are NN and NH, then there is a 50% chance of the horse being NH, regardless of how linebred to Impressive he is, or not, and so on. Any horse going back to Impressive has a risk, unless both parents are NN.[/QUOTE]

Not necessarily true.

I have a huge Palomino QH, no Impressive, but Three Bars. Has had some odd minor tying up issues (or at least that’s what I called it) for years. Seemed to subside for 2 years but I saw one attack recently. Ran full bloods right then, looking for tying up. I was concerned because it lasted longer than normal and came on without energy (apparently, one of the main differences btw HYPP and true tying up). As normal, once the tight muscles/twitching resolved horse was immediately better (again, another one of the main differences btw HYPP and true tying up).

Bloods came back PERFECT, not indicative of true tying up (one moredifferences btw HYPP and true tying up, but you can see elevated muscle relation values with HYPP, which my horse didn’t even have). Ran a HYPP test through UC Davis. N/N. Asked vets and QH breeders- have they ever seen horses without Impressive demonstrate HYPP like symptoms? All agreed they had seen it. AQHA doesn’t want to beleive it. UC Davis’s disclosure does state that they only test for one specific gene mutation.

Vet recommended not treating for tying up if it happens again (which never really helped tremendously), instead to give Karo syrup to alter the Na/K effects. We’ll see if it helps, if he has this problem again.

Said horse is 12 yrs old and never had a serious complication in his life. At first, I freaked out. But my vet, who works on a lot of QH halter and show barns, quickly explained some facts and reassured me that the fact that my horse will drop dead one night are quite slim…

Vet said that the horses that usually have horrible attacks and due quickly are H/H. She didn’t recommend trailering him to the vet’s during an attack, and only recommended calling a vet if it got worse than normal. Granted, I’m pretty keen with that sort of stuff and have lots of meds on hand.

So, did the HYPP start with Impressive or start farther back (Three Bars)?!?

#36

It is much easier than that. The link to UC Davis’s lab was posted earlier. Pluck some mane hairs and throw in $50. They will email the results to you within a week. If you horse is registered, they want to know the parents and their reg. numbers. If you don’t have papers, that’s fine.

But, Like I said, Davis puts the restriction that they only test for one specific gene mutation. There may be others involved…

#37

Your story didn’t prove anything other than we don’t always know what has gone wrong in a horse. I have heard similar stories before. Your horse tested N/N, so unless there is yet another mutation that isn’t tying up, isn’t EPSM, and isn’t the HYPP that we know of today, he’s not HYPP, regardless of his bloodlines.

There IS some speculation about HYPP starting with Three Bars, but it would seem that if that was the case, it’s a different sort of mutation - maybe much less likely to exhibit, doesn’t test as Impressive’s HYPP tests, etc.

#38

So let me ask another question here…say you have a QH that is N/H but has Impressive and his offspring all over the pedigree (3,4,5 back both sides). Does that N/H have more symptoms than say the N/H horse that traces back to Impressive on one side with no inbreeding? Or is N/H all the same?

#39

[QUOTE=findeight;3197140]

Can suggest tracking down where the horse was before last owner had him and trying to discover the breeder. You can track them sometimes that way…try to find a registered name to start.

Yup, that is what started this whole thing. We have been trying to find out his registered name from a previous owner, who only remembered his barn name. I am still trying to find out his real name - which is why we decided to test him rather than wait.

For resale, he may be able to get in with the Palomino folks. There used to be 2 different registries for them, they run shows and all that. It would cost as a hardship but, as a gelding, he may still be eligible. Also depend on the clarity and tone of his color and you’d probably need an inpsector to physically assess him.
But it would increase his resale and create a market.[/QUOTE]

Looked into the Palomino registries - and he is eligible. I was thinking more along the lines of resale value and HYPP - now that we have the results the legal and moral thing here is to release the results. I have to guess that many people would walk away from a HYPP horse and not even consider it.

#40

NH is NH is NH. One copy of the positive presentation, one copy of the negative presentation.

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