Explanation of G-6-S (G-6-Sulfase deficiency)

#1 09/05/14, 07:27 AM

Can someone please explain all of the symptoms of G-6-S? All I have found is failing to grow normally.

And why it is only recommended to test Nubians and not all goats? Nubian crosses, experimentals, unregistered animals with unknown ancestry and other breeds could all be carriers to I would think.

I think it's a good test and once you test once you know for the life of that animal and any resulting offspring.

Here is a link to it's description: http://kinne.net/g6s.htm

Anyone have direct experience with affected animals?

Thanks

**mygoat** · #2 09/05/14, 07:45 AM

Unthriftiness, early death, and poor growth are pretty much all the symptoms of G6S. There are no symptoms for carriers.

G6S is suggested in animals of nubian heritage. The problem is most of those animals are unregistered mutts and the risk is low; thus, they're usually not worth the effort and money of testing. In other breeds, the chance of being a carrier is pretty darn minimal so the value of the test in giving you information you can work with is pretty much nil - no reason to genetic test animals that are highly unlikely to be carriers. I'm certainly not racing to test my french alpines at like 40.00 a pop.

#3 09/05/14, 07:50 AM

Quote:

Originally Posted by mygoat

I'm certainly not racing to test my french alpines at like 40.00 a pop.

Agreed!

Just seems easier to cull for unthriftiness. Test sounds good but priced out of range for someone that would have a signifigant number of animals to test in the beginning.

**mygoat** · #4 09/05/14, 09:15 AM

But it is quite rampant in some lines of nubians. I WOULD DEFINITELY test if I had nubians. If I tested once and removed any carriers, I'd never have to worry about it again if I'm careful in purchasing new animals/bringing in new genetics. That's extremely valuable to me. Or, if i had a carrier doe who was spectacular, I'd only have to test her kids. Without testing, you'll probably catch a lot of flack from nubian breeders and possibly experience decreased prices and reduced interest in your kids for sale.

Testing a large number is a good reason to cull down to your absolute best animals before testing or doing anything labor intensive/expensive. Also, you could test some here and there as your budget allows. You should absolutely test at LEAST your bucks, as they contribute the most genetics to your herd in comparison to any single doe. If your buck is normal (non-carrier), NONE of your kids can EVER be AFFECTED by G6S. It is a simple recessive trait that can only express when it is present in the homozygous recessive genotype. I don't know what the 'industry standard' is as far as the letters used to represent the genotype, but lets say it is G. A normal animal is GG. A carrier is Gg. An affected animal is gg. If you have a carrier doe (Gg) you breed to a normal buck (GG) , you CAN still produce carriers (Gg) offspring 50% of the time. - which means if you keep any bucklings you'd need to continue testing.

Say you don't test your does but you keep a normal buck to sire all your kids (GG). You decide to keep a buckling and get him tested. If he comes back as Gg, you KNOW his dam must also be Gg. You KNOW the sire is NORMAL and could not have contributed the abnormal gene. You know the dam is ONLY a carrier because if she was affected, she'd be runty/stunty and likely culled.

#5 09/05/14, 02:33 PM

Quote:

Originally Posted by mygoat

But it is quite rampant in some lines of nubians. I WOULD DEFINITELY test if I had nubians. If I tested once and removed any carriers, I'd never have to worry about it again if I'm careful in purchasing new animals/bringing in new genetics. That's extremely valuable to me. Or, if i had a carrier doe who was spectacular, I'd only have to test her kids. Without testing, you'll probably catch a lot of flack from nubian breeders and possibly experience decreased prices and reduced interest in your kids for sale.

Testing a large number is a good reason to cull down to your absolute best animals before testing or doing anything labor intensive/expensive. Also, you could test some here and there as your budget allows. You should absolutely test at LEAST your bucks, as they contribute the most genetics to your herd in comparison to any single doe. If your buck is normal (non-carrier), NONE of your kids can EVER be AFFECTED by G6S. It is a simple recessive trait that can only express when it is present in the homozygous recessive genotype. I don't know what the 'industry standard' is as far as the letters used to represent the genotype, but lets say it is G. A normal animal is GG. A carrier is Gg. An affected animal is gg. If you have a carrier doe (Gg) you breed to a normal buck (GG) , you CAN still produce carriers (Gg) offspring 50% of the time. - which means if you keep any bucklings you'd need to continue testing.

Say you don't test your does but you keep a normal buck to sire all your kids (GG). You decide to keep a buckling and get him tested. If he comes back as Gg, you KNOW his dam must also be Gg. You KNOW the sire is NORMAL and could not have contributed the abnormal gene. You know the dam is ONLY a carrier because if she was affected, she'd be runty/stunty and likely culled.

True. And I again agree. But I am not competing with anyone marketing breeding stock. I have not actively sold any kids for several years now and have not added any new animals since 09 that I currently have. If I were to begin selling breeding stock again, I would have G6S done on my herd. That is why I started this thread. But I feel that ALL goat breeders selling breeding stock should have this done, no matter the breed. It is highly unlikely that Nubians are the only breed that carry G6S. If a carrier was introduced somewhere back and continues to pass the gene, they can't be a little bit of a carrier

The studies likely did not have a large enough sample size to say for certain that other breeds are 100% free of G6S. I remember hearing the myth years ago that Nigerians and Boers were resistant to CAE

When I do buy another buck it will be tested for G6S or confirmed by tested parentage. I will also test for myself for CAE and CL. But I am picky on any buck I would purchase. A lot of thought goes into breeding stock.

#6 09/05/14, 03:34 PM

On a side note: Are there any accreditation programs for disease testing in the US similar to what UK and AU have? If not has anyone heard any talking about that?

That would be a great idea for an organization to implement that.

**mygoat** · #7 09/05/14, 09:47 PM

I don't know if there is for dairy goats. I think there is a voluntary Johnes management program for cattle.

As far as other breeds, I do NOT believe all breeds should comply. Literally every research paper and credible literature I could find says that it is a disease associated with nubians and nubian crosses. I could find references to a screening that MSU did after finding the first G6S nubian kid that they fully described (it was a necropsy submittal, it seems) that showed that nubians were the affected breed, but not others - could not find the actual source, it may not be 'valueable' enough to publish (because who cares about goats, lol - only us goat people who barely qualify as an animal 'industry") The reason there was as much research into the frequency of the gene and in what breeds, was actually because G6S is analogous to a human disease that is the same genetically, thus it was important to find out more info. From what I can find, literature states it is nubian and nubian heritage animals only. No info talking about other breeds being affeted. I do not feel that any other breed is responsible to test for this defect due to the extremely low chance of carriers according to the literature. I suppose that means it *could* be possible, but until it is a problem of concern I'm certainly still not rushing to test my French Alpines for it. :P

Backfourty,MI. · #8 09/06/14, 10:21 AM

We raise mini nubians & I have had all mine tested for G6S now &/or bought kids from tested parents & al of mine are normal.
I did have 1 mini nubian buck that tested "Carrier", Thank goodness I only bred him to 1 doe, then I wethered his bucklings & tested the doeling out of him. She was normal, again thank goodness.
Then we culled him. We really Loved him & such a good boy but I just could not see testing every kid that he sired for the rest of his life or would I sell him knowing he was a "Carrier" for the gene.

Cannon_Farms · #9 09/06/14, 02:28 PM

$45 is cheaper than feeding a goat for a couple years before it can crop up. Its a rarity in itself and in my opinion isnt so much as a culling factor, sadly some of the top animals where needlessly butchered instead of being managed, unlike some things its not hard to work with it to go around it, and for anything I would consider having with it, that kids going to be worth more than $45 bucks even as meat. General rule of thumb is that no bucks are used that are carriers so most only test the bucks.

Not as important as other testing but is something nice to know. Its not as bad as HYPP in horses is, in part to responsible breeding.

**mygoat** · #10 09/06/14, 03:07 PM

I too believe it's pretty easily managed. If I were a nubian person, I wouldn't keep any carrier bucks, but I wouldn't mind a carrier doe if she was a good doe. HYPP is pretty easily managed in the same sense, isn't it? If you breed a carrier to a non-carrier, you're safe. You'd have to keep testing the offspring of a carrier animal, but knowledge is power in cases like this.

Cannon_Farms · #11 09/06/14, 04:29 PM

Yea but many breed to get the best regardless of the odds of them having hypp

**mygoat** · #12 09/06/14, 05:46 PM

That's true. And I suppose as a breeder, it is your informed choice to do so or not. I know horses are more companion than they are livestock anymore, so you'd probably catch a lot of flack for breeding two carriers and/or humanely euthanizing the result if it's a carrier (vs trying to manage an affected horse).