Shivers Mare as a Recipient Mare

[halt]

@Daventry

The “changes” in the DNA are environmentally influenced…but the DNA does not actually change. DNA characteristics can be influenced by environment. Horses with OCD is a good example of that. If you feed the horse properly, while they may be genetically predisoposed to the problem, the switch isn’t flipped. You’re not comparing apples to apples.

There’s no doubt that environment influences the final outcome of what the foal is and will be. I’m genetically predisposed to Type II diabetes. However, I watch what I eat and while my brother is now diabetic, I have, so far, managed to dodge that bullet. But, even if I am diagnosed with diabetes at some point, my DNA will NOT change.

The links you posted are referring to cloning, not embryo transfers. Again, cloning is a completely different process than a simple embryo transfer. Cloning involves the use of a donor egg and it does involve mitochondrial DNA…but this is different than an already formed egg being put into a recipient mare for an embryo transfer.

Here’s my chance to bang my head on my desk. DNA does change over an organism’s life time. The pattern of nucleotides does not change, but so many other aspects of DNA does: telomere strand lengths, epigenetics, and DNA sequence/mutations.

Some of the articles are in relation to cloning. Some of them are in relation to oocyte transfer, which includes ET, does it not? I can’t do your reading for you.

[Daventry]

@halt

Here’s my chance to bang my head on my desk. DNA does change over an organism’s life time. The pattern of nucleotides does not change, but so many other aspects of DNA does: telomere strand lengths, epigenetics, and DNA sequence/mutations.

Some of the articles are in relation to cloning. Some of them are in relation to oocyte transfer, which includes ET, does it not? I can’t do your reading for you.

No offense, but you are being deliberately obtuse. You are still not comparing apples to apples. There are processes that “influence” DNA as we age, etc…but the building blocks do not change. If you do a DNA test, the result will show the same parentage. You are claiming that an outside source can pass on some of it’s DNA to the embryo, i.e. the recipient mare.

Hetroplasmy is a completely different subject, as it is addressing how much mitochondrial DNA is in each cell of the individual…but it is not from an outside source. There is also a difference between oocyte transfer and cloning. With cloning, you are removing the genetic material from within the egg, not merely and simply transferring the ova. Oocyte transfer is done with ICSI, but the donor egg DNA does not change. You are not removing the DNA from it. Yes, you do an oocyte transfer with cloning as well, but the process isn’t simply using the ova to create an embryo.

Again, head on over to the EquineRepro group on Facebook. The equine repro experts on there can explain things a lot better than I can and it will probably help make things a lot clearer.

I’m done discussing this interesting topic. Gotta get some work done today.

[JB]

Horses CAN have identical twins. Just because it’s rare doesn’t mean it can’t happen. To my knowledge it’s been reported a handful of times. In cows it happens a lot more (relatively speaking).

It MtDNA from recipient can become part of a transfer in cows, that means it is possible in horses. Maybe it hasn’t been proven yet, and that would make it unfair to say it does happen, however rarely. But it does add credence to the belief that it could.

Epigentics is phenotype vs genotype. It is just changes to gene expression - on or off. So no, while characteristics of DNA change - overall health, length - the DNA sequence does not change in such a way that previously testing as the parent of a child now makes you test as no. That sequence is the same.

[sdlbredfan]

@epowers

I managed and foaled out a mare with shivers, she was in my care for roughly a year and a half (from breeding to weaning). She was a bit tricky to work on her hind feet, and she struggled to back up or turn in tight circles but it otherwise didn’t really affect her much. She had no trouble foaling or anything. I know it’s a couple years later now and the mare is in foal again.

I hope that mare was a recipient, not carrying her own foal!

[vineyridge]

When making your decision, remember that the foal will be receiving its blood and nutrition through the recipient mare. They will carry her chemicals to the foal and may also have an impact on what genes are turned on and off during the process of gestation.

Given how little we know about how environmental factors from the carrying mare affect the final foal, this is a risk that I personally wouldn’t take under the current lack of definitive science on the topic.