Speed VLOG
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Speed VLOG

October 19, 2019

Alright, so we’re going to have a little
bit of a conversation today about an interesting topic in the equine industry, and what is
that topic today, Mrs. Kocher? The topic out of an article is “Racing for
Disaster?: Breeding thoroughbreds for speed may harm their health.” Okay, Mrs. Kocher, interesting article, but
let’s talk about this a little bit. So, we read articles like this all the time (All
the time) and it’s interesting this article is published in… (Catchy titles) catchy
title, this is in Science, so it’s a relatively reliable source, we’ll talk about that a
little bit later on, but the first thing we might ask is, well, who’s the author of
this particular article? That’s right. It says it’s Ann Gibbons. Ann Gibbons. So, we went and looked up her
bio, here’s her bio, we’re going to go ahead and bring that up, you guys can take
a look at that. She’s a scientific journalist, she seems relatively reliable, and if she’s
writing for a peer article like Science, we’ll give her the benefit of the doubt here a little
bit. She probably knows a little bit about genetics, she understands these areas, and
she writes a pretty good article here. Absolutely, but we do want to question, some
of these articles are for entertainment value, as well. Sure. So, this sounds very ominous; the health of
the thoroughbred industry. Well, that’s how you draw the reader in,
right? Absolutely, but we’d also like to critically
assess the article and see what she says in here, and possibly some counter article to
this. Good. So, let’s look at a couple points
through the article. So, one of the things that Ann Gibbons, the
author of this article, brings up is a little bit of back-ground about California Chrome.
Do you know who California Chrome was, or is? Yeah, he won the Kentucky Derby and the Preakness
(Absolutely), and disappointingly he lost the Belmont. Fell short at the Belmont, absolutely. That seems to happen a lot. Yes. So, what she stated was that he was “common
stock,” he was from an “unspectacular mare,” or the wrong side of the thoroughbred
tracks, as you may. I’ve said that about me sometimes, too. Oh, that’s disappointing. That is disappointing, yeah, well, you know. So, basically what they’re saying was, California
Chrome was a nothing thoroughbred, and that was one of the questions that were raised
in here, but Dr. Staniar, was he a common thorough-bred? Well, it would be pretty exciting if he was,
wouldn’t it? (It would be absolutely exciting) I mean, hey, we could all go out…(Right
out of my backyard.) Right, exactly. (And breed that thorough-bred). Right, but if we
actually look at his pedigree, and we’ve got some of it here, so I’m going to go
ahead and throw it up on the screen here, we can go through and circle some particularly
good stock back there (He’s a blue blood). It’s not to say that he is in the upper
echelon of what we would say, well, that’s the perfect, sort of, breeding lines for a
thoroughbred, but for the most part, thoroughbreds have a lot of similar horses in their background,
which might bring up this question of being inbred or not. Okay, so I need a better definition of what
inbred is. Well, so do I, and in a second, we’ll bring
in Dr. Dechow and maybe he can help us with some of those questions. But I asked Dr. Dechow
to look through a few articles before we do that, and I think this is a part of your question
of looking for reliable sources. Absolutely, I would love to know a little
bit more about a reliable source, and have our students and our viewers understand what
a reliable source is. Not to say that Ann Gibbons’ article is not reliable, but there
are some questions we’re going to pull out of here that we might want to better understand
or ask (sure) while reading this. So, a reliable source it’s all relative,
right? And so, again, we try our best to find a large number of different pieces of evidence
that maybe support our particular stance, or opinion, or the facts that we’re looking
for. A good source for that information tends to be scientifically refereed journals, which
are journals in which a number of different individuals have read that article and have
de-termined that, yes, the information there is good and it’s valuable to us going forward
and making decisions based on the information. So, two of the articles that we’ve got here,
one talks about inbreeding in the thoroughbred, and it sort of states that perhaps the current
inbreeding rates, and we’ll talk about those in a little bit, are worrisome, but it doesn’t
outright say that it’s bad. And a lot of times you’ll notice inbreeding
used in text or writing is used as a negative thing. And then, in the other article, it talks about
the inheritance, or the potential inheritance, of aspects of performance or speed in the
horse, and so that’s an interesting article as well. In a nutshell, it comes down to the
fact that, while there appears to be some heritability of those particular traits, at
this point, it’s relatively limited, actually, and so that will bring up a whole other question
as to, what are the limits of speed in this particular animal? But let’s go talk to
Dr. Dechow. Alright, we’re talking about this interesting topic, and to help us out
with some of the information that we have brought in Dr. Chad Dechow. He is out geneticist
within the department of Animal Science, many of you that are students in this class will
have him in class someday. But we have some basic questions here, and we thought that
Dr. Dechow might be able to answer some of those for us. Okay, I’ll try. Alright, great. One of the topics that comes
up in this conversation, in some of the material that we’re looking at, is that Thoroughbreds
have somehow become inbred, that we have an inbred population. What does that mean, to
be inbred, when we talk about our livestock species? Well, what it means is that there’s basically
just less genetic diversity (okay) then there was at earlier times, and we’ve got more
of our genes that are homozygous (okay) than there were in the past. Is that a bad thing? It can be a bad thing, but keep in mind that
when we do genetic selection, our goal is to concen-trate the best genes as rapidly
as we can, and so, when we do that, we tend to get more homozy-gosity of the best genes.
So, on that side it’s good. The flip side is that we also know that there are some developmental
genes that, if we get two copies of a defective gene, we end up with a lethal embryo condition.
There is a downside to it as well, and that’s why we want to try to avoid it to some degree
and to manage it. Okay, that helps a little bit. Is there, how
do we decide whether we have too much inbreeding or not? What are some of the things that,
for example, the Thoroughbred industry, should be looking for that would tell us, yes, we
have too much inbreeding or, no, we’re pretty good right now. The old joke among animal breeders is that,
if it works it’s called ‘line breeding,’ and if something bad happens, we call it ‘inbreeding.’
But, I think the main thing is that you have to look at current levels of inbreeding and
associate it with a horse’s performance for different traits, and if you that, yeah,
the inbred animals really do have more problems of some sort, then that kind of gives you
an idea of what the current population can handle, and if you’ve gone too far or not.
So it’s really there’s no ‘this is too much inbreeding,’ it’s ‘at what point
does inbreeding start to impair the per-formance of the horse.’ You had a chance to look at some of the articles
we look at. One is, one talks about, kind of tries to put some numbers on inbreeding
in the Thoroughbred, and you’ve voiced some interest in, sort of, comparing that to what
we see perhaps, and an example comes up in the dairy industry. How might you compare
the two of those? Based on the numbers in those papers, we’ve
had a lot higher rate of inbreeding in dairy cattle than we have in horses, since 1960,
because we have more intense genetic selection in dairy cat-tle for specific traits in a
shorter generation interval. Since 1960, dairy cattle have accumulated more inbreeding than
horses, but, on the flip side, dairy cattle have a large founder population that horses,
so they started out with more variation. So, I don’t know that we can really, or at least
I don’t have a good sense of how much genetic diversity is there in the Thoroughbred population
versus relative to the dairy cattle population today. So, it’s hard to make a direct comparison,
but I would say the rate of inbreeding in Thoroughbreds is not high. Well, that’s perfect, that, I think that
helps a lot. One of the other papers, and I’m going to read a quote from that paper,
and I wonder if you might, sort of, tell us what you think about this. It says, “However,
the major advantage is that racing performance may be evaluated in both males and females
and repeated observations can be obtained on the same animal in a relatively short peri-od.
These factors coupled with the reasonable heritability of some measures of racing perfor-mance,
suggest that mass selection based on performance tests would be the selection proce-dure of
choice to improve the racing performance of Thoroughbred horses.” What’s being de-scribed
there? They’re describing a lot of things there.
One of the things that they’re describing is that, for ex-ample, in dairy cows, bulls
don’t give milk, which creates an additional complication, but in horses, both males and
females can race. (Right.) So, they have a little bit of an advantage there. The relatively
short time period between races, you can get many observations on an animal pretty quickly,
which gives us a better sense of their genetic potential fairly quickly. So, those are ad-vantages
horses may have compared to some other species. And then, in addition to that, there are some
measures of racing performance that have reasonable heritability, so what the author is suggesting
is that we can measure, we can determine who the best racing animals are early on in their
life and then use those animals to become our breeding stock. So, the fastest mare are
go-ing to mate with the fastest stallions. Okay. Ultimately, what’s our best bet? That’s kind of what you’ve been doing.
What happens is that the generation interval in horses is very long, ten years on average
when you decide, kind of wait until a stallion has completed his career, say he was a great
horse, I want to get as many foals out of him as I can now. But my perspective, as a
dairy cattle breeder, you would make that decision early on and say we think this is
a good stallion, we’re going to use him now, maybe we don’t use too much one stallion.
We use a little bit of that stallion here, and then if he turns out to have been a dud,
well, we won’t have too many lousy offspring from him. But to me, the generation interval
is the big limiting fac-tor. Right. Any other thoughts you have on this
before we go ahead and leave and head back? No, it’s just it’s really interesting
to compare what’s happened in the horse industry to the dairy cattle industry. Alright, well, Dr. Dechow, thank you very
much for coming in and joining us today. No problem. And maybe we’ll have you back again sometime. Alright. Thank you. Great, thanks. We’re going to go ahead and
show a picture here. Here we’re talking about the winning race times for Thoroughbreds
in the Triple Crown series. So, the Kentucky Derby, the Preakness and the Belmont. And
so, what’s one of the things that stands out to you in this partic-ular graph? That the times haven’t changed a whole lot,
we’ve been pretty stagnant with racing times. You can see there’s a little bit of fluctuation
when there might be a big winner, and I’m assuming you can see Secretariat’s. If you
look at all the years of racing, we really haven’t improved on times. Right. And so those racing times really haven’t
improved since about the 1960s, and so there are lots of questions as to why that hasn’t
happened and why there hasn’t been improvement in that, and we’ll talk about some of that
as we go through. Alright, so as we talk about all this, you know, it’s always interesting
to look at what the, quote-unquote, experts think, right? And so, I’ve got a quote here,
from Dr. David Kronfeld, from and article in The Blood Horse. Wait, and who is Dr. David Kronfeld? So, Dr. David Kronfeld happened to be my PhD
advisor at Virginia Tech. Okay. But, was also somebody that was very much
involved in the horse industry. So, if I read this quote, he says this is out of his article
called “Speed Limit” which was published in The Blood Horse, “This dismal prospect
of an increasingly fragile racing Thoroughbred is a challenge to owners and breeders. They
are left to grapple with the ethical issues, the economic realities, and the inevitable
conundrum that environmental management of the side effects of breeding for speed aims
to help the individual, while weakening the breed.” It’s very interesting; it sounds like a
rock and a hard place. It does, and that’s exactly what he talks
about in the article, because he says that, look, when we select a Thoroughbred to run
very fast, we might also be selecting for some traits that are health problems that
we see. Examples of those might be EIPH, which is ‘exercise induced pulmonary hemorrhage’,
or bleeding, maybe gastric ulcers, problems like that. So, he focused on… His statement here, basically
says breeding for speed comes along with, or these diseases come along with breeding
for speed. So, imagine how hard it is to breed for an animal that doesn’t have those things,
but is a speedy animal; or do they get slower? Exactly. So, I think that that’s something
that’s an ongoing question, to tell you the truth, today. It’s something that we
still have to grapple with as an industry, how to do that. It also represents some opportunities
that we have for the environmental managements aspect of things. Think about; how are we
feeding these animals, how are we managing them, how are we growing them, what are the
things that we can do? We know what those particular diseases or conditions are that
are associated with speed. What can we do to best manage those? And we have to be care-ful
when we say that because we should always also be thinking about the genetic side of
things, of not ignoring them, but thinking about okay, how can we manage them in the
horses that we have today, while at the same time, trying to improve the genetics so we
see less of those prob-lems occurring in the long term? Okay. So, earlier, we looked at a great graph,
I think is a wonderful graph, of the times for Thor-oughbreds (Sure) in the three largest,
the jewels of the Triple Crown (Right) and how they have not improved over that time,
except for the wonderful anomaly, Secretariat, that I have to keep bringing up (Sure). So,
does that mean we can’t improve on speed? What about dog racing, what about Quarter
Horse racing, have they improved? And those are just the questions that would be generated
from this article. Sure. Actually, this has been looked at, in
a relatively limited sense, and so, here is another arti-cle that has looked at this,
and so this particular article looks at limits, and that question of the limit of speed in
horses, dogs and humans, actually. And humans is a great, great point because
what about racing, just the humans racing, or just swimming? They’re constantly breaking
world records, US records. Why can’t we get to that point where we’re improving? So, I think that what the data seems to indicate
is that we have actually reached the limit of speed in our current stock of, whether
it be Thoroughbreds or greyhounds, and we’ve bred them relative-ly intensively, as we’ve
been talking about (Yup) for that particular performance characteristic. So, it appears
that from a physiologic standpoint, we may have reached that limit of speed. Now, I’m
going to go ahead and read a quote out of that same paper, that I think is quite interesting
in regard to where we might go, or what the possibilities might be. Now, this is a sort
of out of reali-ty, because the Thoroughbred industry right now is a closed registry, but
what might we do? “In a larger sense, however, the equine
data presented here are preliminary at best. It may well be possible that different criteria
for selective breeding of horses could produce a faster animal. Thoroughbreds have been recognized
as a separate breed since the 1700s, and regulation of the breed has constrained its gene pool:
Thoroughbreds are less genetically diverse than other breeds of horses. The breed is
effectively a closed lineage descended from as few as 12-29 indi-viduals, and 95 percent
of the paternal lineages in present-day Thoroughbreds can be traced to a single stallion, The Darley
Arabian. Selective breeding starting with different equine stock could perhaps yield
faster horses. In this sense, then, the results presented here do not necessarily address
the question of the maximum speed for the species Equus cabillus.”
Okay so, we’ve spent a very short amount of time talking about a very complex topic,
and there’s no way that we can cover this topic appropriately in the amount of time
that we have. Time flies when you’re having fun. It does fly when you’re having fun, and
I really enjoy this. There are a lot of questions that remain in regard to this particular topic,
and I will tell you that we actually spent a lot of time outside of producing this 10-15
minute vlog where we pulled together a lot of different data sources and tried to incorporate
some good information for you all. Having said that, this is a topic that you could
spend days and days talking about, and people do. Some of the questions that remain, I think,
are; one, are we breeding for speed or durability in the Thoroughbred? I don’t know that there’s
a clear answer to that question, it’s one that, certainly, many people are interested
in looking at, but I’m not sure that there’s a clear answer to that. Another question is; are Thoroughbreds inbred,
and if they are, is that a bad thing or a good thing? Just another question. Have Thoroughbreds reached their limit of
speed? Can we, no matter how much we breed, may-be they’re just physiologically not
capable of running any faster. Have we reached that limit? Is there enough variance in the
breed that would allow us to do that, or do we have to go by some other techniques? Right, and another question we didn’t answer,
and is a very good one; are we racing for disaster? The title was catchy, certainly
caught our eye, but is it disastrous? Is it a downfall of the Thor-oughbred industry;
the racing and the breeding? I don’t think so, but certainly a question that we haven’t
answered. So, these are all thing to think about, and
I think it highlights that, from a relatively simple, straight-forward article, we can raise
a lot of questions, and there are a lot of things for the horse industry to be talking
about. And this doesn’t just involve just the Thoroughbred industry, it really means
the horse industry as a whole, and thinking about what we’re doing with each of our
breeds that’s beneficial or detrimental and what the future holds as we go forward.
So, we want to thank you guys for joining us (very much, for sticking with us) for our
very first vlog. It will be interesting to look back on this one as the years go forward. And cringe, probably. Right. It’s going to be cringe worthy. Right, exactly, and see where things go. But
this was the first one, so we’ll see how it all goes and I hope this has left you with
a lot of questions and makes you go out and do a little bit of re-search on your own.

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