This is the first in a series of presentations given at the 2022 Tri-State Dairy Nutrition Conference. Epigenetics of different environments and reactions is the topic at hand, presented by Dr. Jack Britt of Jack H Britt Consulting.
Guests: Dr. Jack Britt, Jack H Britt Consulting
This is the first in a series of presentations given at the 2022 Tri-State Dairy Nutrition Conference. Epigenetics of different environments and reactions is the topic at hand, presented by Dr. Jack Britt of Jack H Britt Consulting.
Dr. Britt begins by clarifying that epigenetics (transmittable changes in genetic behavior of an individual), are only beginning to be understood. This is partly due to the intricacies of DNA. For instance, the expression of DNA can vary greatly and the process of synthesizing a protein is much more complex than DNA to RNA to protein. 5:32
The tendency of DNA to change over time is the focus of epigenetics, creating positive DNA changes is the focus of multiple dairy cattle studies discussed.
After pointing out that epigenetics is mainly influenced by environment and management, Dr. Britt discusses its implications by giving an example of the pregnant cow. Each pregnant cow represents three separate generations at one time: the cow, fetus, and ovaries in the fetus. 8:34
Genes multiply to produce new life and continue multiplying after birth in various types of cells. Thus, Dr. Britt notes that a change in a gene, such as when a methyl group alters DNA expression, that alteration multiplies along with the gene, creating an epigenetic effect. 11:25
Studying epigenetics is commonly done in twins, Dr. Britt gives the example of his identical twin brother. His brother died of Parkinson’s disease a few years ago, demonstrating that the disease is an epigenetic (due to environmental change) disease instead of a genetic one. 14:56
What are areas where epigenetics have significantly impacted the production of dairy cattle?
Numerous cases are detailed by Dr. Britt, one being the decrease in fertility that correlates with a body condition score loss after calving. An oocyte matures in approximately 101 days, meaning it begins to develop soon after calving, when the cow is potentially at the lowest weight. The egg produced by this cow typically dies 4-5 days after fertilization. 23:07
Technology has created improvements in environment and management factors. Dr. Britt references the University of Guelph, where a new technology is being used to monitor and distribute calves’ energy intake to ensure they consistently gain weight during weaning. 28:57
Concluding his talk, Dr. Britt poses the question: How can technology be used to create a reputable activity score of important factors among each herd? Such a score would allow for long term comparison across herds, allowing for epigenetics to estimate performance. 33:45
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Scott (00:07):
Good evening everyone, and welcome to the Real Science Exchange, the pubcast where leading scientists and industry professionals meet over a few drinks to discuss the latest ideas and trends in animal nutrition. Hi, I'm Scott Sorrell. I'll be your host here tonight for tonight's conversation. We're doing something a bit different tonight. We're releasing a series of four presentations given at a symposia at the 2022 Tri-State Nutrition Conference. We're gonna release those as four separate podcasts. The title of the symposia was Exploring in Utero Influences on Transgenerational Performance. The speakers and topics at the symposium were, we started off with Dr. Jack Britt. His title was called Epigenetics Will Change How We Manage Cattle. We then followed that with Dr. Jimena Laporta from the University of Wisconsin. Her talk was titled Phenotypic and Molecular Signatures of Fetal Hypothermia. Then our third talk was given by Dr. Eric Capo. He's from Balchem Corporation, and his title was The Growing Importance of Choline in Prenatal Human Nutrition. Then we had batting cleanup was Dr. Pete Hanson from the University of Florida. His talk was titled methyl Donors and Epigenetic Regulation of the Early Embryo. Before we get started, I'd like to welcome back our co-host, Dr. Clay Zimmerman. Clay, good to see you again.
Clay (01:28):
Good to see you, Scott. Thanks.
Scott (01:30):
Alright. Thanks for coming along.
Speaker 3 (01:31):
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Scott (01:53):
Let's now go to Dr. Jack Britt as he explains that we are in the early stages of understanding epigenetics, and he looks into his crystal ball to give us the his view of what this may mean to the dairy industry.
Dr. Britt (02:10):
Epigenetics is a relatively new concept for us, and we're simply at the early stages of learning about epigenetics. It was first discovered, if you will, or talked about in the 1940s or so. But we're just now beginning to understand what happens and how it happens in all species, and it's gonna be an important aspect of what we do in the future in terms of managing our herds and flocks and, and resources. I wanna point out that I don't work alone. There's a team of people shown on the bottom of this slide that is part of my team. We work together a lot. We've published papers together. We discussed issues both that this is an international group, and so we learn from each other. What I'm really going to do is give an overview of epigenetics. I'm really not an epigeneticist. I don't know there's anyone who's an epigeneticist Peter, but we're gonna be talking about what I've learned and what others have learned in terms of epigenetics.
Dr. Britt (03:23):
The first thing I want to indicate is there are two terms that you might hear epigenetics and epigenomics, and it's not always been clear what they mean. So recently, n i h has a study group that focuses on epigenetics, and they say that we ought to use these two terms in this way. Epigenetics refers to changes in the genetic behavior, if you will, of an individual that can be transmitted to their offspring and to their offspring and to their offspring for at least multiple generations. Now, the DNA sequence hasn't changed, but the way the DNA behaves has changed with that epigenetic change, we also can have epigenomics and that can refer to what happens in an individual animal as it develops, so that the genetic control of stem cells, let's say mammary mammary gland cells, stem cells, or stem cells in the gut may be affected differently and that may or may not be transmitted to the next generation.
Dr. Britt (04:42):
And we'll show you some examples of those. I think I'm a member of the DNA era , and I say that because DNA, the structure of DNA, was published in 1953, and we built this dairy barn on our farm in 1953 in the spring, the same time that Watson and Creek published the structure of DNA. So I'm a, I'm an early part of ADNA era, I would say early on, if you look at the box on the bottom left, that was our concept of how DNA was translated and transcribed into proteins and how it worked. The earliest understanding of this process resulted in a Nobel Prize, and it was pretty simple. DNA made r n a and r n a made a protein, and that's the way everything worked.
Dr. Britt (05:43):
We thought that all of the, all of the problems had been solved in understanding genetics, but then as time has moved on, we now know that it's much more complicated than that three steps. We have DNA, which is, which is has normally as it normally has been developed over the years or defined over the years but we also have methylated DNA. We can have methyl groups on some of the residues of the DNA, and we have stated his stones that the DNA is wrapped around in the nucleus. So these are structures that were, were not known in the early days, but they then influence how DNA functions. And then we have a whole group of, of RNAs, short RNAs, long RNAs, long non-coding RNAs that can play roles in genetic expression rather than making a protein, those RNAs may go back and bind to the DNA to regulate its expression.
Dr. Britt (06:57):
And so that's a step that is very important in understanding epigenetics. Some genes are expressed or not expressed, what we know is, that essentially every gene is turned off in a normal process in the oocyte and sperm, and then those are turned back on. So epigenetics is really a process that works in development throughout life. But we haven't understood exactly how it might be altered or be irregular to cause effects until now. So, expression of DNA can vary a lot in many ways. And that's really what we talk about as we talk about epigenetics
Scott (07:48):
Play. Dr. Britt gave us an explanation of DNA methylation. Can you summarize that for us and then explain Cho's role as a methyl donor? Sure.
Clay (07:57):
Yeah. So first of all, I thought Dr. Britt did an excellent job leading off this symposium, really setting up the topic of epi of epigenetics for the audience. So essentially, methylation is what DNA methylation is that turns off or on the expression of the genes that are in DNA. So he used an example at the beginning near the beginning of the presentation saying that, you know, in, in gametes, so you know, whether it's an osis in a female or, or sperm in a male, that the you know, the DNA is there, but the genes are turned off at that point. They're not being expressed at that point. You know, it's not until conception happens that that that DNA is methylating genes, genes are turned on to be expressed at that point.
Clay (09:05):
So you know, he utilized a number of examples to talk about epigenetic effects, but he went through a number of examples explaining how, you know, the, it's actually been 70 years now, which kind of amazes me. It's been 70 years now since Watson and, and Andrick came up with, you know, the double helix structure of DNA. It's hard to believe it's been that long that that's been known now. But then you know, we continue to learn more and more about, you know, about the whole sequence. You know, originally we thought, you know, DNA was, was, you know, translated to mRNA, and then the mRNA would build proteins, and that's a very sim simplistic view, but there's a lot that we're really just learning about methylation of DNA and you know, how that, how that impacts gene expression.
Clay (10:14):
So, choline, choline is a very key methyl donor in the mother. So choline actually contains three different methyl groups you know, unlike some other methyl donors that are out there. So, you know, choline is a very key source of methyl compounds for methyl don donation to this, you know, to the mother for the developing fetus. And as we move through these talks, you know, as part of the mini symposium, we'll learn more and more about this, how, how DNA methylation can play different roles in, in the, in the life cycle process.
Scott (11:04):
All right, thank you, clay. Love it. Now let's get back to the presentation.
Dr. Britt (11:10):
Dr. John Cole, who was at USDA and is now uses, put together a whole series of data in the last couple of years looking at how various performance traits have changed over the last 50 years. And he used 1957 as the base. And then he calculated, based on what we know about changes in DNA and management, what percentage increases over this last 50 years have occurred to make milk production go up in the US dairy herd. And you can see that about 24% of the improvement was associated with environment and management, and about 30% was associated with genetics. Those are pretty close, almost equal, about half of it genetics and about half of it environment and management, we would say right now that epigenetics falls that into that environment and management area rather than in the genetic area, because it's caused by changes in the environment and how animals are treated or fed or how they live. But in the future, as we understand it, we may move that up into the genetic area. It may become another com, a component of genetics in the future. So right now we consider it to be an environmental factor or effect, but in the future, we may be measuring monitoring epigenetics the same way me way we measure genes and, and genomic activity today.
Dr. Britt (12:58):
Now, one of the things that I wanna point out to you is that any pregnant cow represents three generations at the same time. And this is something I believe is very important for us to think about and remember, the cow is generation one, the fetus and the uterus is generation two, and the gametes in the ovaries or testes of that fetus is generation three. So while sometimes we think we are affecting the cow or maybe the cow and the calf, we may miss the idea that we are affecting three generations with an environmental impact. Think about epigenetics. We have to think about the fact that three gen generations can be affected by the same environmental factor that occurs. Could be a disease, it could be change in temperature, it could be change in feeding. It could be lots of different things that would induce that.
Dr. Britt (14:03):
But we do have, in a pregnant animal, three generations represented, as I indicated, the cyte and the sperm shown on the left, which are one end. At that stage of development are all the genes are turned off. And then after fertilization, some genes are turned on and they begin to develop, and they develop the blast cyst, which begins to grow in the uterus, uc, or uterus. And other genes are turned on to regulate the development of certain organs in the body. And that continues really throughout life development and repair changes in our tissues. Not only do we have those changes in the development for various parts of the body, but we can have changes in the cells that form the mammary cells or the, or the uterine or the intestinal cells. The cells that multiply and multiply and multiply over life.
Dr. Britt (15:14):
Skin cells, for example, can also be affected. So we have various generations, if you will, and various types of cells that can be affected by genetics and epigenetic turnover. Now, if we go to the DNA level, if we look at the level of DNA, and we look at it chemically, we have begun to understand a little bit about what happens with epigenetics. The first thing that was really discovered was that some bases in the DNA have a methyl group attached to them, and there are enzymes that control that to put the methyl group on the DNA. And so it's not unusual to find methyl groups attached to the d a, but when methyl groups are attached to the DNA, that changes the DNA expression, that's an epigenetic change. The DNA sequence hasn't changed, but that methyl group on one base can change how the DNA behaves. And then the DNA is wrapped around histone proteins, and some of the histone proteins can become acetylated. And when they're rated, that changes how the DNA can open up or unwind or unroll from his stones and become expressible. And so epigenetics is related to these two processes that happen within the nucleus within the cell.
Dr. Britt (17:00):
One of the ways of studying epigenetics is look at, is to look at identical twins early in life and late in life. This picture on the left is my twin brother and I, when we were between three and four years old. Now, identical twins in their early life, by and large, are in the same environment. They're in the same family. They eat the same food, they're taken care of by the same people. They get the same medical care, but then they move apart. So my brother and I moved apart, worked in different areas after we got outta college. That's a picture of us on the right in Mexico, working with some dairy herds there when we were 57 years old. So we had worked apart, if you will, for about 30 years. At that time, my brother was diagnosed with Parkinson's disease in his late thirties or early forties, and he lived until four years ago.
Dr. Britt (18:15):
We were identical twins. Parkinson's disease is not a genetic disorder, but there's more and more evidence that Parkinson's disease is an epigenetic disorder. In fact, there are many papers being published in that area now. So this says something in his environment was different than something in my environment. During most of our careers, we don't know what that is. People say, well, is it some medicine he used or was it something he used in the clinic, or was it something he used to treat cows? We really don't know. But he obviously was living in a different environment than I was. And so that's an example of an epigenetic disease or effect that has been demonstrated.
Dr. Britt (19:01):
A study in Spain is demonstrated in those boxes across the top, and they took identical twins from about four countries, and they measured the markers on the DNA, the methylation of the D DNA or the acetylation of the histones in those identical twins. And the red bars are twins that were always three years of age. And you can see the red bars are always exactly the same in the sets of twins. Now, the older bars were from twins that were 55 years of age. It's not the same, same individuals, but these older twins had lived apart for most of their life. And if you look at those blue bars in every measure, the two twins are statistically different in terms of how that particular sedation or methylation had occurred in their DNA. So clearly there's evidence that over life, our DNA changes through environmental influences without the DNA sequence changing at all. And so this results into what we refer to as epigenetic effects.
Dr. Britt (20:27):
One of the things that epigenetic effects do is to really keep the DNA from relaxing, if you will, and opening it up so that the enzymes, the polymerases that act on the DNA to make r n a can, can function. And on the left, we would see what a normal helix of DNA might look like when it's opened up. On the right, we see what might be a helix after it's been affected by epigenetics. It simply doesn't have the wherewithal, if you will, to open the spiral open and for it to be expressed normally. And so this is a way that is something as simple as a methyl group or an acetyl group can change whether genes are expressed or not during life.
Dr. Britt (21:27):
Now, when we start thinking about epigenetics, we have to think about activities that occur or changes that occur over a period of time. And I, I'll give you just a few examples here that we know of in dairy cattle that we expect are related to epigenetics, but we don't know the exact mechanisms yet. For example, if you milk fresh cows four times a day for the first three to four weeks of lactation, and then you go back to two times milking for the rest of lactation, they will produce more milk throughout the entire lactation, even though they're still, they'll only be a milk two times a day like the other cows for most of the lactation. So something happens to the mammary cells in that first three to four weeks when they're milled four times a day, that influences the activity of the mammary cells for the rest of lactation. So that would be one example.
Dr. Britt (22:33):
We also know that if you have a greater loss in body condition score, body weight change in the first three weeks after calving, that fertility is much lower out at 80 or 90 days when you breed the cow. So what is there between that first three weeks and what happens 90 days later, 80 days later? That would be epigenetics. We have pretty good data, basically looking at genomic expectations and, and actual performance that if you do I V F or embryo transfer multiple ovulation and embryo transfer the, the embryo is not exactly the same as an embryo that is produced naturally. And when you go back and look at the numbers, they never quite reach what they would expect it to be based on our genetic equations. Heat stress clearly, clearly. One of our speakers and her team at Florida have, have worked, or when she was at Florida, worked on this, this heat stress can not only affect the pregnant animal, but the fetus and several subsequent generations. And we'll show you a little more data on that.
Dr. Britt (24:01):
There's some evidence that fetal development in heifers, a heifer that's being developed in a heifer, actually has better health than a heifer that is developing in a lactating cow. And, and probably that's related to the fact that in a lactating cow, the calf is competing with the heifer for nutrients to be supplied through the feed and, and body weight changes may be occurring. It may be subjected more to body weight loss, for example, negative energy balance. So we have several examples in cattle that genetically are the same, but in terms of performance are different. Lemme talk a little bit about this observation that we made several years ago. It's referred to as the Brit hypothesis. We were looking at changes in body condition and Holstein cows. This was back in the nineties.
Dr. Britt (25:07):
And we simply took a group of cows. We had about 45 or 50 cows in this batch of cows that were in a study that pub. This was not published in the pre, in the, in the original paper, but we did the analysis later and published this. You notice we have two patterns of body weight change in the cows in the box in the center. One is fairly maintained. We just labeled that as maintained body condition score. And the other group you see lost significantly in body condition score during the first five or six weeks, and then returned back to almost the same as the other group by the eight to 10 weeks. And these cows were then inseminated about 85 days postpartum artificial insemination without timed ai.
Dr. Britt (26:01):
And look at the difference in fertility. The cows that maintained their body condition score had a 62% conception rate, and those that lost weight and then regained the weight had a 25% conception rate out at the time of breeding. Their body condition scores were almost identical, but they had different patterns in the postpartum period of how those body weight changes. And so we got to thinking about this, and we, we then thought about that cyte that is released at the time of ovulation out at 80 or 85 days has been growing for a while, and we started working our way back. It turns out that it takes a cyte about 101 days from the time it's activated in the ovary to, to continue to grow and the follicle and to be ovulated. So it can be inseminated about 101 days. And so if you go out at 82 days or so and trace back that cyte that is ovulated at 82 days or so began its development during the transition period, during the time when the cow was losing most of its weight, the body weight changes in the transition period.
Dr. Britt (27:23):
So our theory was that it was subjected to an impact through the granulosa cells that influenced its fertility. Later on a group at Wisconsin, it used data from two herds. There's about 1800 cows in this study. They simply measured the body condition score change in the first three weeks after cavity, and they put 'em into three classes. They had cows that lost body condition score, cows that maintained body condition score, and cows that gained body condition score in the first three weeks after Calvin. The nutritions there argued, we don't have any cows that don't lose weight
Dr. Britt (28:34):
And you can look at the different differences in conception rate or fertility to that timed ai, 25%, 38%, 84%, which clearly shows that that cyte out at 80 days or so has been influenced by the body weight changes just after calving. So that's an example of an epigenetic effect somehow that cyte has been impacted negatively. Now what's interesting, if you go ahead and look at the rest of the studies that they did with this, those eggs are actually fertilized and begin to grow and all die before the fourth or fifth day after fertilization. So that means that their genetic development was impaired apparently by the heat stress or, or the body weight change stress that occurred much earlier. We see the same sort of thing with heat stress and other stresses in cattle.
Dr. Britt (29:37):
One of the questions that we have to ask, why do cows have to lose weight? And this is a study from Israel, one of their big dairy centers research centers, and these cows were all fed the same and they simply monitored their body weight and their body condition. On the left, you see the percentage of body weight loss. This is natural loss not caused by changes in diet. They were all feeding the same diet and they watch, they followed cows through five lactations. And you can see there's clearly two patterns of activity. Some cows lose a lot of weight, some do not lose nearly as much weight. If you look at the milk production, it's the same. The cows that lose less weight, produce more protein and more fat. So cows don't have to lose weight or as much weight, if you will, to be as productive. On the right side is the fertility of these cows, and you can see that the low, the low losers, if you will, compared to the high losers were more fertile. They had fewer days open and higher first service conception rates. So I'll get again an example of how an environment can change the performance of these cows.
Dr. Britt (31:04):
These are data from Pete Hansen's group and, and others looking at embryos. And on the left we have the cumulative death rate of embryos during the first six months after the embryo was after the calf was born. And these calves were produced by artificial insemination as the regular method or by in vitro production conventional or Ivf with sex semen or with moit. And on the right, we have their performance, their milk yield, gestational length, and so on and so forth. Now, you would expect that the embryos subjected to IVF and embryo transfer moat were better embryos because they're coming from the genetically the best cows, but they do not beat the controls when you look at milk yield. And so this means that their performance has somehow been impaired a bit by the way they've been handled in vitro. This doesn't mean we should stop doing moot and in vitro fertilization, but clearly there's a difference between those embryos and embryos that are produced naturally. And so that would be another example of epigenetic effects.
Dr. Britt (32:40):
One way to deal with these kinds of changes that we see is to have a mechanism so that we control or prevent those adverse effects. These are calves in a new calf facility at the University of Guelph, and they're doing something I think very intriguing here. You know, we typically wean calves at a certain day of age, but the calves that are weaned at a certain day of age are not gaining the same amount, are eating the amount. And so what they've done is have an electronic milk feeder and an electronic creep feeder for calf starter. All the calves have a tag, electronic tag, and the computer monitors their energy intake every day, and it makes the transition from milk to milk replacer always result in them gaining weight. They don't have any ch changes or any weight changes that are ga or losses because the computer is regulating really how much energy that comes in. And so this would be an example of how we could use technology to prevent some of the epigenetic effects that we might see if you simply wing calves on the same day. Some are going to perform a whole lot differently than others because of the differences in their natural intakes. And if you can make that intake, not of just milk or grain, but of energy continue to increase, then you won't see this effect.
Dr. Britt (34:27):
These are data from the Florida study I mentioned earlier. On the left we have cows that were either cooled or not cooled during the last 46 days of pregnancy. The last 46 days and cooling was simply using ventilation system sprinklers, typical system for cooling cows. They weren't put in air conditioned buildings. They were simply cooled during the last 46 days of gestation. The bottom chart on the left shows their meal, their milk yield in the subsequent lactation, depending on whether they were heat stressed or cooled. And you can see those cows that were cooled in the last 46 days produce more milk than those that were not cooled. We've always thought, you know, we're the, the, the dry cows, okay, we don't have to worry about cooling. But now it looks like in a heat stressed environment, we need to cool everything, the calves and cows and dry cows and all others.
Dr. Britt (35:36):
The next two boxes of graphs show the first three lactations and the calves that resulted from those cows. The next box over number three is the second generation. And what this shows is that over three lactations with the first generation and one lactation for the second generation, if they're, if they came from the cooled line, if you will, the cooled dams originally, they continued to produce more milk than if they came from the heat stress line. Now, every animal was cooled after that first 46 days. All the calves were always cooled while they were pregnant. So this is a generational effect that goes back to heat stressed calves. Three, two or three generations earlier, is continued from one generation to the next.
Dr. Britt (36:37):
Now, the biggest challenge I think we have today is how do we get data to measure epigenetics? Where's that data gonna come from? We really need to be measuring activity. We need to be measuring body stress, heat stress, cool stress. We've got a lot of tools to do that. But our biggest challenge is, those tools don't talk to each other. How many different methods do we have monitoring activity in cows or monitoring rumination in cows or, or monitoring speed of milk production in cows? Anything that you want, want to talk about. We have lots of different tools, but there's not a consistent method. So we need to get the companies and the organizations and the breeders and the dairymen to start thinking about can we develop a consistent activity score? You know, that's it, it may be 1, 2, 3, 4, or one to five, low to high, but we need methods of measuring things in a way that we can compare that we don't have the data to do today.
Dr. Britt (38:01):
If we really want to understand epigenetics in the future, we need to know what the body temperature is in every herd every day. We probably need to know when the new silo was opened in that herd or when the T M R was mixed for that herd. Or we changed equipment in milking or maybe even individual employees in milking if we're gonna understand how these influence the genetic expression of the cow and the, and her future calves. And so this is what really epigenetics is about. And in 20 years from now, we will have proofs in which epigenetics is used to estimate the performance of the next generation. I wanna thank you for your opportunity to spend time with you. Remember, only the questions from Lex. This lecture will be on the, on the exam. So thank you very much.
Speaker 3 (39:02):
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Scott (39:25):
Now, clay, I think Dr. Britt was the, the, the perfect lead off to this series. I thought he did a great job leading us off. Do you have any final thoughts you'd like to leave with our audience? Thought
Clay (39:36):
He was the perfect lead off to this. I really, you know, I really enjoyed some of the examples that he shared towards the end of the presentation on different examples of epigenetics and dairy cows. You know, ones that we think about off, it was a good lead into some of the other talk. One of his examples was the four x milking of fresh cows and how that's affecting epigenetics as we in very early lactation and, and taking those cows back, you know, to a two x or three x milking and the improved milk yield there. He talked quite a bit about, you know, increased body condition loss in very early lactation, you know, increased body condition loss the first three weeks postpartum and how that can affect fertility 80 days postpartum. He talked about heat stress during late lactation, so heat stress, you know, the last six weeks prepartum in that dam and how that affects the cow and the next two generations which was a great lead into the, to the next speaker. Speaker. Yeah,
Scott (40:42):
I found that very interesting.
Clay (40:43):
So there I thought he did a great job setting this up.
Scott (40:48):
Alright, thank you Clay, as always. It's been great having you here in the co-pilot seat to our audience. Be sure to look for the next podcast in the series that'll come out next week. We'll be featuring Dr. Jimena LaPorta and her presentation titled The Phenotypic and Molecular Signatures of Fetal Hyperthermia. And to our loyal listeners, as always, we want to thank you for joining us for tonight's conversation. We hope you learned something. I hope you had some fun, and we hope to see you next time here at Real Science Exchange, where it's always happy hour and you're always among friends.
Speaker 3 (41:20):
We'd love to hear your comments or ideas for topics and guests. So please reach out via email to anh.marketing at balchem.com with any suggestions and we'll work hard to add them to the schedule. Don't forget to leave a five star rating on your way out. You can request your Real Science Exchange t-shirt in just a few easy steps, just like or subscribe to the Real Science Exchange. And send us a screenshot along with your address and t-shirt size to anh.marketing at balchem.com. Balchems real science lecture series of webinars continues with ruminant focused topics on the first Tuesday of every month. Monogastric focused topics on the second Tuesday of each month, and quarterly topics for the companion animal segment. Visit balchem.com/realscience to see the latest schedule enter, register for upcoming webinars.