Hello, this is Brian Sloan from Adisseo. I am the Director of our SmartLine Business worldwide. It's my pleasure today to present to you our first webinar in a series of six, 2023 is the 30th anniversary of amino acid balancing. And we'll broach that a little more, not only in this webinar but in the subsequent webinars in this series. The aim of this first webinar is to look at the effects of amino acid balancing principally on productive effects, both milk yield and components. But before we get there in this first series, we will also look at the historic elements of amino acid balancing. Where did it start? And where are we today? In the subsequent five webinars, we will address other parts of the advantages of amino acid balancing on reproduction, transition cow and metabolic health, longevity, sustainability. And with a final webinar which will focus on the formulation of practical rations in terms of amino acid balancing. Without further ado I would like to welcome and introduce my two esteemed guests for today's webinar. First, we have Professor Emeritus Charles Schwab. He has devoted the majority of his academic life to furthering the knowledge of amino acid balancing in dairy. First during his Ph.D. work in Wisconsin and subsequently during his career at the University of New Hampshire, where he was both researcher and an educator. He continues to be very active as a consultant to the industry. My second guest is Franck Gaudin. Originally from Brittany and France, Franck came to the US over 20 years ago and has held various posts in the dairy feed industry. Today he is the dairy director at Big Gain Feed. Frank also has a consultancy business outside the US called Vision Lait, where he takes the opportunity to give advice and guidelines to a variety of organizations worldwide. His particular objective in most of this or vocation is to help organizations maximize or achieve high productivity of energy corrected milk with a particular focus on profitability and feed efficiency. Welcome gentlemen! Chuck, before we go any further, I think it would be good for the audience to have your definition of amino acid balancing because that is the crux of how we will formulate rations. Can you just give us your definition of amino acid balancing, please? Thank you, Brian. This would be my definition. It's our goal for sure. It's a deliberate attempt through the selective use of protein and Rumen Protected amino acid supplements, to achieve an amount profile of absorbed amino acids that comes as close as possible to meeting the cow's requirements for optimum health and performance without wasting amino acids. And if we can achieve that, and that should really be our goal, the benefits would be number one, reduces need for supplemental rumen undegraded feed protein (RUP). More predictable responses to two supplemental RUP, and thus MP. Reduces the risk of cows experiencing an amino acid deficiency. And finally, it permits maximizing production and most efficient use of dietary nitrogen. Franck would you have anything to add to that? In terms of your practical perception of amino acid balancing? Yes, Brian. Amino acid balancing for me has been a very good tool in predicting performances. For a certain level of nutrients we are capable of predicting production irregardless of the level of production. It is accurate at 30 kg and it's also accurate at 40 kg. As long as the nutrient allows this production. Thank you, Frank. Chuck, I know that often you like to emphasize to people who perhaps are a little bit new to amino acid balancing, the importance of using amino acid balancing to use protein efficiently in the diet. Perhaps in just a few words, you could you know, just talk people through how they can think about this in a pragmatic way. Thanks Brian. This slide. Is really an attempt to show how powerful amino acid balancing can be at least with respect to lysine and methionine, and the amount of RUP that's required. If we're not amino acid balancing, we may well have a diet that's going to look like the first diet here. And in order to achieve 180g of metabolizable lysine and 60g of metabolizable methionine. If one goes through the calculations here, the diet is going to have to contain 7.6% RUP. On the flip side, if we're very aggressive, with our amino acid balancing with respect to lysine and methionine, and getting those levels up there very close to what we think the optimum levels are, by being very selective in our use of protein supplements in rumen protected lysine and rumen protected methionine supplements. We can achieve those levels, there are 6.9% and 2.3% lysine and methionine, and MP. And if you read way over to the right hand side of the table now, the diet only needs to contain 4.9% RUP to achieve that 180g of MP lysine and 60g of MP methionine. Chuck, I think that's a really important point for people just, you know, start to think about how to practically implement amino acid balancing, how much RUP or MP you can eventually economize if you approach this correctly. But perhaps before we go any further, we can let you see how you got interested in this whole area of amino acid balances and give us a little bit of the background to your Ph.D. because basically, that was the first work that I'm aware of where it really was proven that amino acid balancing or amino acid limitations existed in dairy cows. And therefore there was an opportunity to improve the amino acid status of cows with positive effects on milk performance. Actually, I got interested in this whole topic of amino acid balancing in my senior year as an undergraduate student in 1969. And so I went on to University of Wisconsin Madison for my master's and Ph.D. In the beginning of my Ph.D. program, my advisor and I agreed that the time was right to really take a good look and try and figure out what the first limiting amino acids were and what their sequence of limitation were, when we fed diets or practical diets to lactating dairy cows. And at that point in time, what we knew is that lactating cows would respond to casein, supplemental casein, if infused into the small intestine. And there were some other indirect approaches that had been used to try and determine sequence of amino acid limitation, but there was really no direct evidence. So what we decided to do was to conduct five experiments. They were all Latin-square studies and we looked at 13 different treatment combinations and some of those treatment combinations we use more than once. So these were abomasal infusion studies, where amino acids were infused into the cows on a continuous basis, experimental periods were nine days long. And another decision that we made was to feed low protein diets without protein supplementation because we figured that if we could sequence amino acids limitation without protein supplements, then we would get a better idea as to what the sequence and extent of limitation would be when we added protein supplements to the diet. And what we observed is that 93% of the total response that we got in milk protein yield by infusing the 10 essential amino acids, casein was obtained with lysine, methionine, histidine, threonine, isoleucine valine, and phenylalanine. So those six amino acids gave us 93% of the total response that we got when we infused all the essentials or all the amino acids in terms of casein. Interestingly lysine and methionine together accounted for 43% of that total response. And this surprised us just a little bit that the effect of lysine and methionine would account for that much of the total response. And that was confirmed in four out of the five studies, the effects also were on content of milk protein rather than on milk yield. So, the conclusions were that we couldn't really tell if lysine was more limiting or if it was co-limiting with methionine. But we got by far the biggest effect on the production response with the two together. Secondly, we concluded that the amounts of protein that escaped rumen degradation from each feed stuff are large enough to offset the higher concentrations of lysine and methionine and mixed microbial protein and we'll see that on the next slide. And lastly, because of differences in feed proteins, amino acid composition, and extend a rumen degradation, we concluded that the ingredient composition of the diet will ultimately influence which amino acids are most limiting in the extent of their limitation. So this next slide and the reason that I said we were a little surprised really by the impact of supplemental lysine and methionine when we were feeding these low protein diets, was that we were only feeding forages and an energy feed. So the three forages that you see here of alfalfa hay, corn, grass hay, they were in the diet and corn was in the diet as an energy feed and oats was also in there as well. Unfortunately, I don't have oats here in this table. The values in red here as noted in the bottom of the slide is that these are 80% or less than the values in milk. So, if you go to the top of the table up there, you'll see the lysine concentrations in milk and mix microbial protein and you'll see the methionine concentrations there. Now known as all the feeds that we fed the concentrations of lysine is 80% or less of that, of which we see in mixed rumen microbes. So we had some idea that lysine would probably be a limiting amino acid, methionine that was a little bit more of a surprise. Notice that alfalfa hay, grass hay, certainly had lower values of methionine in them. So what this slide really shows, I think is that not only did it confirm that looking at the amino acid composition of our feedstuffs gives us some idea as to whether or not they're going to be limiting in the diet or not. But then you go to the bottom of the table and look at the protein supplements and notice that in all cases, the lysine concentrations are 80% or less that of mixed microbial protein. And most feedstuffs also have a much lower content of methionine. So it's really not a surprise. It shouldn't be a surprise to anybody that these two amino acids are the most limiting. Thanks, Chuck. I mean, 40 years later or maybe it's even, maybe it's more than 40 years. I mean between what you did in your Ph.D. and just looking at typical profiles of amino acids within feedstuffs. Our basic premise for the last 10 years are that lysine and methionine are the first two limiting amino acids. And if already we rectify that we can see no substantial responses in terms of milk performance. Franck I wonder if what I said rings true to you as well? Is that what you've seen over the last few years that typically with the ingredients you encounter, that lysine and methionine are the two most limiting amino acids. And there is real opportunity just to pay attention to these first two in terms of improving performance. Absolutely, Brian, I think the introduction of rumen protected lysine and methionine validates that because as we use those products more readily and we increase supply of those products, we continue to see an improvement in milk production. So it's never been more true than it is today. And I go back in the seventies, Chuck, we didn't have the formulation tools perhaps to take advantage of that. I think one big milestone that happened in the early nineties was the French who at least then, seem to be ahead of the game. They introduced some of the first principles of amino acid formulation guidelines. Perhaps you would like to explain what they did and how that was a major step forward to begin actually formulating for amino acids in dairy cows? Well, that was definitely a breakthrough in terms of allowing nutritionist in the industry to appreciate how important it is to ensure that we got adequate supplies of lysine and methionine and metabolizable protein. I followed with great interest the French PDI (digestable protein of the small intestin) system, which did a great job of predicting protein supply in terms of microbial protein and RUP. And then the development of the amino acid sub-model that was integrated then into that protein model. Dr. Rulquin and colleagues over there, I think just did a remarkable job in developing a factorial based model that predicted very accurately the amino acid composition of protein flowing to the small intestine. And while it was a factorial approach, you might expect that some of those amino acids were predicted a little bit higher, a little bit lower than measured. And so they went back into the model and they made adjustments to the model to correct for that. So the end result was they had a model that just did a super job on predicting amino acid composition of protein flowing to the small intestine. They then took that model and we encountered the same issue, there was not enough data available for us to develop models that would predict amino acid requirements. In other words, grams per day of each amino acid. But what we were able to do because we had models now that did a good job, and in this case, the French model, of predicting amino acids into ENDOU protein. They used all the amino acid studies where they infused individual amino acids, different amounts of lysine, different amounts of methionine into the small intestine. Measured animal responses, run those diets through the model and develop these dose response plots for lysine and methionine. So their conclusion was, with their model, the optimum concentration of lysine and metabolizable protein in terms of the NRC system or the PDI system here in this case, that the optimum level of 7.3% lysine and digestible protein, and methionine was 2.5%. So these became then the targeted values for nutritionists to use. And that was a gigantic leap forward in terms of being able to amino acid balance. So these then really became known as the requirements for lysine and methionine and metabolizable protein using their model. I remember when I first came to the US in Canada in the mid nineties, I had been living in France and therefore had been using these numbers. And my first attempt was to use all these as reference even when trying to amino acid balance rations in North America. I think what was probably important is that when you served on the NRC 2001 committee, you were inspired by this, these approaches by the French, and in many ways I gave you the Black Bone for how you put together the guidelines and pseudo recommendations for amino acid balancing. For the NRC 2001, perhaps you would like to say for North America how that developed and how that became basically the launching pad for amino acid balancing. Exactly, so the approach was, and our vision was that we needed a model that would predict as accurately as possible, the proportional amounts of RDP and RUP in each feedstuff as total feed intake changed. We recognize that the time had come where we needed to make sure that we're providing a mixed rumen microbes in the rumen with adequate amounts of rumen degradable protein. So we needed a system here to predict as accurately as we could now, the amounts of RDP and the amounts of RUP within a ration and that meant being able to predict those in each feedstuff. Number two, we knew we needed to consider differences in intestinal digestibility of RUP among feedstuffs. Number three, we needed to predict flows of metabolizable protein and the proportional contributions of microbial protein and RUP to MP as accurately as possible. So we went to great lengths here within the protein model itself, to be able to do that as accurately as possible. And that meant with the data that was available to us at the time. And certainly the model had to predict the content of each essential amino acid and MP as accurately as possible. So our approach to the development of the model was somewhat different than the protein and amino acids sub-model in the European system. But our degree of accuracy was just as good if not a little bit better than their system at that time. I didn't think that we really had any choice but to think about amino acid requirements and in this case, lysine and methionine requirements in terms of their concentrations in MP. We just didn't have enough data to develop a factorial system. And so we use the same approach then as Dr. Rulquin did for developing these dose response plots. And noticed that our determined optimums here were 7.2% and 2.4%, slightly different but still very close to the optimums that were observed with the French model, in which they used a different approach in the development of the model, but yet our values here are very similar. Another thing that a number of people I think really appreciated and we certainly did, in the development of the model how accurate the NRC model was then in predicting flows of lysine and methionine to the small intestine. So really not a lot of scatter above these lines, just very accurate. And again the whole focus really, the greatest focused on both the European model or the French model and the NRC, was to be as able to predict flows and percentages of both lysine and methionine and MP as accurately as possible. And I think we achieved that. Franck maybe you can, when that was published and you saw the first results of NRC 2001, what were the take home message you took from that? And how did that influence how you then developed in practice your approach to amino acid balancing? Well, I think Brian, what happened with Chuck's work, he made it feel very simple. And as we can see on that bottom slide, when we look at supply of lysine and grams, as we increase grams of lysine, the protein yield was influenced positively. And that triggered a light in my head and I said, well, this needs to be applied in the field because as we increase production, we're going to help producers improve their income over feed cost. So this was, I would say a little revolution for me. And that's when I started to be very interested in trying to duplicate what Chuck had worked on and apply it in the field. So that comes up. Since then, how have you progressively incorporated amino acid balancing as a core nutrient specification within your overall rationing approach? And what have you observed over the last 20 years in terms of the application, and improvement and that you've been able to implement? Yes, as I said, Chuck made it appear very simple, but reality came in and it was not as simple as I was expecting. Because from 2001 to 2013, we were focusing or at least I was focusing maybe more on MP and RUP and sometimes forgetting the basic that RDP was still needed. And the rumen contribution is important in your total gram supply. So it took a little bit of time and I guess in 2014, I was lucky to work closely with Chuck and he explained all of his work and it allowed us to understand all the interaction between RDP and MP, and rumen contribution. That's when we started focusing on grams and making sure rumen efficiency was still there. After 2014, we migrated to a period between 2015-2021 I would say, we started, in 2014 I remember some of my top herds were averaging 150-160g of lysine. And we started increasing the supply and every time we would increase the supply, we would get a milk response. So we got very excited. We have done this every year, where we increase 10g to 12g of metabolizable lysine with the combination of metabolizable methionine. To get us today to 2022, with a much higher supply than what we had in 2015 and of course much higher production. So very exciting development by following Chuck's road map, it has brought in a lot more income over feed cost to our clients as well. Thanks for sharing your experience with us Franck. And as you said, at the end the results have been very impressive, but there has been a learning experience and one other thing that has happened is that originally we focus very much on milk protein. But in fact, on the benefit side, some of the effects have been as impressive on milk fat as milk protein. And therefore, the simple question of what we call the limiting amino acid theory is a little bit more complicated than we first thought, particularly for methionine. Chuck maybe you'd like to share your thoughts on the uniqueness of methionine's role in amino acid balancing. It's taken all of us a number of years to really appreciate this but definitely methionine is more than just a building block for protein. On the flip side, I guess we've recognized ever since we got into this business that methionine is an important methyl donor. This has been a subject very well researched in the last 50-60 years. It's involved in the methylation of proteins and DNA synthesis of creatine and so on, including the regulation of gene expression and one carbon unit metabolism. So this is a powerful, a very important function of methionine, where it's going to have an influence on metabolism over and beyond just as a building block for protein. The second thing is there are several important metabolites in the body that are all synthesized from methionine and these would include things like homocysteine, taurine, glutathione, and in parentheses here, I've indicated what some of their most important functions are. So these are all metabolites that are synthesized from methionine and the requirement in the body for these various metabolites are probably going to go up and down or be altered if you will, by the health and the production of the animal. So lots of important effects here of these downstream metabolites of methionine that we may not think of as important functions of methionine. But yet all of these products are synthesized from methionine. And finally, like some a few other amino acids that we've come to appreciate here in recent years is that it stimulates mTOR, which in turn influences protein synthesis and in that capacity then, through mTOR methionine is up regulating genes and enzymes in the mammary gland which increases the efficiency of use of amino acids for the synthesis of milk protein. So, if you put all this together, the result of these functions is that methionine is having a profound effect on the efficiency of use of all the amino acids for protein synthesis. And in that way, very important then in promoting better health and reproduction. Thanks, Chuck. Perhaps it is a good time for me to plug the subsequent webinars which will give you much more detail on some of these other benefits of amino acid balancing, particular role of methionine on a reproduction and health. But what I'd like to do now is share with you our compilation that Adisseo has done of all the research that we have carried out with people like Chuck, but many other institutions around the world over the last 20-30 years. So when we look at the number of studies, what we call a continuous nature where we fed product for anywhere between 6 to 15 weeks of lactation. And we put all that together, as Chuck indicated earlier the first thing you virtually always see when you're amino acid balancing is a major uptick in terms of milk protein concentration. So, as you see from this compilation, the average was 0.13% which is not surprising to any of us around this table because even since the nineties, that 0.13%, 0.14% or 0.15% has sort of been taken as the expectation for increase in milk protein percent. I think what is a little bit more surprising is that the actual increase in milk fat percentage is of the same order of magnitude, if not higher. In this compilation the average increase in milk fat was 0.16%. A benefit that has been confirmed, I think in the early days, we were always a little uncertain of any effect on milk fat because milk fat is very variable in trials and often even a large numeric increase does not come through as being significant. So it's only when you put together a large body of data that you can see what is the more the tendency, the more the confirmation of that effect on milk fat. Obviously, this is in terms of percentage and certainly for areas of the world where there's heavy bonuses in terms of extra milk fat and protein, what's important is how does that translate into extra grams of fat and protein? Here, you can see that though when you have what I call long term experimentation, the type of increase in terms of milk protein can be of the order on average 60g per day and over 80g in terms of milk fat, that's a total of over 140g of increase in total components. So, this is very important for the industry. And again, I think before this compilation some people in the industry were a little skeptical of the order of magnitude of increases that can be attained. And the other way to look at this is in fact when you put all that together under what I call one key performance indicator or energy corrected milk. Because I think that for many progressive people in the industry is what they track nowadays, it's energy corrected milk, which takes into account the benefits on yield, protein and fat all under the one number you can see here. The average increase in energy corrected milk is of the order of 1.7kg per day. When you do amino acid balancing and you correct the deficiencies in terms of lysine and methionine that we talked about, this is the type of increase in performance that you can can expect. I'm gonna ask probably the same question to Chuck and to Franck, but to Chuck more in the scientific angle and then Franck more on the practical angle. When you see this, is this surprising to you to see these, on average large increases in performance, not only in milk protein but milk fat? Perhaps let you take the question first Chuck. It was surprising, I think initially to see this impact on milk fat, the feedback was that some dairy nutritionists were seeing that others were not seeing that sometimes in research, we didn't see that. But in some cases, those were Latin-square type of studies and what you summarized here, Brian are the longitudinal type of studies, these were not Latin-square type of studies, this is where cows went on to the treatments and they stayed on those treatments to the end of the experiment. So a little bit more time if you will for the animals to adjust. Early on, my reaction to this or my response to this was that it's pretty hard to imagine, really in any aspect of fatty acid metabolism or lipid metabolism that doesn't first involve protein synthesis. In other words, fat cannot be digested without enzymes, fat cannot be transported in the blood without the aid of proteins, fat can't be catabolized or synthesized without the aid of enzymes within the cells or without enzymes being involved. So, protein synthesis always has to precede any aspect of fatty acid metabolism and fat synthesis. So that's sort of an easy answer if you will as to why we see a positive effect on milk fat when we supplement the diets with methionine. Now, what we didn't give early credit really to here is that methionine also acts as a functional nutrient. And I alluded to that a little bit earlier. Where we know now that methionine itself, as well as some of the downstream metabolites help regulate genes and enzymes that are not only involved in the synthesis of protein but also in the synthesis of fat, again enzymes are involved. In the mechanism of this really and I think we're gonna continue to learn more and more about this, but one is the impact that methionine has on mTOR and the effect that mTOR has on overall lipid or fatty acid metabolism. And then there is a second regulatory factor known as SREBP-1 sterol regulatory element binding transcriptor factor one, that is a well established, and you can find a lot of data in the literature on this, especially in non-ruminal animals, that's a master regulator of fat synthesis and homeostasis both within the liver and in the mammary gland. So as a required nutrient, then it just makes sense that if methionine is in short supply lipid metabolism in one way or another is gonna be affected. And if we make the diet adequate in methionine then all of the machinery involved in lipid metabolism will be enhanced. Thanks, Chuck. From the practical side, how soon did you start to observe these types of responses in the herds you were working with? Was this something that was evident pretty early on or has it been again, as you said earlier, a work in progress? And it's only today that you can confirm that the effects on fat are similar or greater to the effects on milk protein. No, I think Brian, the effect on milk fat came very early on. And I think one of the early slide that Chuck presented really illustrated that before we migrated, at looking at just gram supply, as I said, we were looking at increasing MP. But what we forgot is due to your metabolized protein, it was not respected. And as we learn and again, migrated to looking at grams and we improve the profile of lysine and percent of MP. We saw a clear response of butter fat and I believe that had to do with supplying the adequate level of RDP as well and improving ruminal function altogether and fiber degradation. That was a result of better understanding how the amino acid interact and work altogether. What I'm hearing Franck is there was a basic amino acid balancing effect on milk fat, but also you were learning at the same time, maybe other things that were also helping to even improve that milk fat response further by paying attention to certain rumen parameters. I know you've worked in many areas around the world, have you seen any differences in terms of cows around the world? And then in terms of how they respond to amino acid balancing? Well, the one thing we've learned is no matter where you're at Brian in the world, a cow is a cow and that specific cow in China, France or North America respond to increased supply of amino acid. And we've been fortunate to work with a group here in the US but also a group in Western France. Ans we're seeing the same exact response in France. We don't have quite as high of a supply of lysine or methionine, therefore, the performance are related to that supply and here in the US, higher supply yields, higher milk response. But at the end of the day, what Chuck unfolded in 2001 with his release of NRC, works no matter where you're at. And it's actually been a lot of fun to bring this information everywhere in the world and seeing the producers see the producers acceptance to these findings has been kind of fun. I like your use of the word fun there. UIt can be fun sometimes it can be a little bit exasperating at times as well. And I think, one part of all this is how do we keep putting this into practice, therefore, in terms of formulation and what really are the key things we should be formulating for when we establish formulation constraints. And so I suppose, as we're coming to the end here, I would just like to have some comments from you both about the should we ever even still be talking about crude protein and MP? Where do they play in terms of roles as formulation constraints going forward or should we focus uniquely on amino acids? Chuck, maybe you go first. I put my thoughts to paper here, Brian on that and we certainly can't just look at amino acid balancing, and Franck has certainly stated this here a few times, we have to make sure that the animals are getting adequate amounts of RDP. We want optimum rumen function and I think a few times too often, we see in the quest to lower crude protein in the diet, that what really gets short changed in the diet is rumen degradable protein. And so we have to keep our eyes on that and probably our models and our inputs and everything makes it really more difficult sometimes to know exactly what the real RDP is. So, at the farm level, sometimes we have to play around with that just to make sure that we're not short changing the rumen non-RDP and thus, which is gonna affect feed intake, it's gonna affect milk production and that sort of thing. I honestly think that ration code protein really as a targeted nutrient rationed entity needs to be dropped, from all ration formulation models. It just seems way too often that people keep their eyes on that and by keeping their eyes on it, it's misleading them and its presence just continues to reinforce his long held belief that there's an optimum dietary concentration that must be met and that is not true. The optimums that we need to be striving for is on RDP and grams of absorbed amino acids. I do think that ration formulation problems, models probably need to continue with requirements for MP. But if so those MP requirements need to be adjusted for amino acid balance. And most ration formulation models do not do that. And because they don't, you got to have confidence in being able to feed less MP or in some cases more MP depending if you're amino acid balancing or not. I think most models are doing this now, RDP and RUP requirements need to be expressed as a percentage of dietary or should not be expressed as a percentage of dietary food protein, but as a percent of diet diet matter. And the reason is they provide nitrogen amino acids for two distinctly different purposes. And I like to hear Franck's comment on that actually. Absorbed amino acids requirements as they currently are expressed in grams per day as percentages of MP and as grams per Mcal of absorbed energy, I think we need to look at them in all three of these ways. And then I alluded to this already, but I think if we need to keep MP, because I think we all want to see what the predicted amounts of lysine and methionine, and MP are, if we don't want to call it MP, we could just call it absorbed amino acids. But I think we need something here to scale lysine and methionine requirements or needs of. So those would be my comments. Thanks Chuck. Just to lead on, Franck, I know that you have adopted early on a formulation system that allowed you to adjust MP for the quantities of lysine and methionine that were being supplied and therefore not get caught in terms of unnecessarily over formulating in terms of MP. But I'm sure there's other things that you've learned over time when you're formulating for amino acids to keep everything inbounds across all nutrients. And perhaps you could just share a little bit your practical experience about how you go about balancing rations today to get optimum performance. Well, remember I had a good professor. So it's gonna be very much in line with Chuck. Very quickly after our training with Chuck, we migrated to total grams supplied. But as Chuck mentioned, we can't forget RDP because rumen microbial protein is part of this total gram. So when we formulate, we have a software that today we ask for certain supply of grams and then we're making sure we're meeting RDP. And then third, we're looking at concentration of lysine and MP as Chuck stated and of course, energy supply has to be also in correlation with your amino acid supply. But again, as far as crude protein or MP, these are two units that we're not looking at directly, but in indirectly. Perhaps I could just ask an additional question to you Franck, because I think it's not a formulation constraint per say. But in terms of, when you start to look at the long term development of performance on a dairy, I think you've told me recently that you have been, particularly interested in how to use amino acid balancing, but in correlation with other nutrient supplies to improve feed efficiency. Perhaps, could you just tell us a little bit about this concept and how it's influencing the way that you go about rations today. Well, we are looking at feed efficiency because we know that feed efficiency is correlated with the income over feed cost. The the other point that we're unfolded is that increase in feed efficiency has been allowed or permitted because of ingredient like protected methionine or protected lysine. As we have those ingredients available, we have been able to concentrate the amount of grams per kilogram or per pound of feed. And as we concentrate the amount of grams per kilo at equal intake, the cow is now able to produce more milk and the more milk we produce, the more efficiency become because she's in part diluting some of our maintenance requirement. So, this feed efficiency seems to be really important for the future in terms of sustainable dairy in the broad sense because we need to produce more from less, if we are going to have a sustainable dairy industry and an environment that we all can continue to live and profit from. Which leads to the last question for this particular webinar to both you and Chuck. What are we going to see in the next 10 years in terms of amino acid balancing, what's going to be key? What is it going to bring? Chuck, you can share your vision of where will we be 10 years from now? Models continue to improve for sure. And that's been very helpful. But I think in the next 10 years and Franck is already doing this, just driving to formulate for better amino acid and feed efficiency. And this requires at least with respect to amino acids balancing rations for individual amino acids and not their aggregate, which is metabolizable protein. So we either need to take our eyes off of metabolizable protein or the models need to adjust that requirement. Now, based on what the amino acid supply is with respect to the most limiting amino acids. I think we're just gonna continue to see an increase in adoption of balancing diets for amino acids. And the industry cannot just continue to ignore the importance that low levels of lysine, methionine, histidine, and now some other amino acids, especially some of the branch chain amino acids are beginning to surface as having an effect and impact really on the efficiency of MP utilization by the animal. What we haven't talked about today and that would be true in the slides that you presented there, Brian that you folks put together, is that those responses to amino acid balancing are much more profound in the transition cow than in cows in later lactation. So we're just seeing some phenomenal responses out in the field. Research has documented that as well. The powerful effect that balancing for optimum levels here of the most limiting amino acids have on cows during that transition period. So I think we're gonna see more rumen protected amino acids coming to the market. I think we definitely need histidine and I think in some cases, we might need amino acids like leucine or isoleucine to raise the bar even a little bit further in terms of what the mammary gland and the efficiency by which a mammary gland can synthesize milk protein. So I think the models are just gonna continue to develop The new NRC model which came out in 2021, that's definitely lots of improvements there over the 2001 model. And then the next version of CNCPS that's coming out again, definitely a better definition of amino acid requirements and how best to meet those requirements. And hopefully, more researchers will get involved here. And of course, we're really doing it with models at this point in time and that's identifying what that ideal profile is of absorbed amino acids for cows at different stages of lactation and production levels. I think this is an area that more researchers really need to challenge the models that we've got in the models that are coming out. So I appreciate you sharing that vision with us, Chuck. And so I'll ask Franck a little bit the same question from a practical point of view, perhaps how he sees the adoption of a new amino acid balancing continuing and what will be the consequences for performance in the feed industry. But I think as Chuck has mentioned, we are going to continue improving models and prediction and, I put a few steps in this slide and personally, we're continuing to focus on maximizing microbial yield with looking at RDP profile, impacting microbial protein yield. We're looking maybe at defining carbohydrates fraction within our model a little better. Again, linked to better microbial yield production. On the RUP from feedstuff or ingredients we wanna continue to look at actual profile of those feedstuff and digestibility on the rumen protected amino acid. What is going to be important is really define bioavailability of those specific rumen protected amino acid. And then as we alluded in some of the previous conversation is we are going to focus heavily on feed efficiency and how can we reach 2.0 feed efficiency. I believe it's gonna come from continuing to increase amino acid concentration per pound of dry matter. As Chuck also mentioned, the relationship between different amino acid and maybe the availability of new protected amino acid, not to ignore the energy supply in relationship of a supply of amino acid as well. And therefore, understanding the interaction will probably help us achieve better amino acid efficiency. This is some of the vision we have today. Thank you so much Franck and Chuck! I've really enjoyed our conversation today and I think in the little time we spent together, we've been able to trace where amino acid balancing has come from, what it is already doing today and confirming that the benefits on milk and milk composition are really of a considerable magnitude and important, and therefore they bring the benefits not only in terms of cow performance, but cow profitability. This sets us up well for our subsequent webinars where we will go into more detail on some of the other aspects. Because as you will see in this sequence of webinars, the benefits in terms of profitability are not just from improvements in performance, but are also related to the aspects of reproduction and metabolic health because these in addition, make will ensure that the lifetime performance of animals are improved and they last longer in the herd, which in terms of sustainable goals will be very important for the future. So again, Chuck and Franck, thank you so much for joining me today and have a pleasant rest of your day. Thank you so much. Thank you.