Hello, everybody. This is Brian Sloan from Adisseo I'd like to welcome you today to the fifth of our six part webinar series on the benefits and advantages of amino acid balancing on dairy rations. In today's webinar, we'd like to focus on the aspect of sustainability. And as we all know, in the past few years, there has become increasing attention to the problems of global warming and therefore the necessity to reduce the carbon footprint of all industries and the agricultural industry is no exception. So we'll look at this aspect today in this current webinar. But first I'd like to welcome our guests today who are going to discuss this important topic with us, and Dr. Chris Reynolds from the University of Reading. Chris is an American national but saw the light and moved to the UK 20 years ago now probably Chris, and has been, all his career very interested in how to improve and evolve nutrition of dairy cows, particularly in terms of efficiency. I also would like to welcome Dr. Lauren Thiaucourt, and he's a veterinarian by education. But again, he very much, during his career, has focused on being part of the feed industry. A very early adopter of amino acid balancing in France and currently in his so-called retirement. He is a consultant around the world to various feed companies to help them improve the nutrition of dairy cows around the world. So welcome, gentlemen. The first question to just, let's say, warm up the proceedings. I'd like to ask you both, you know, about your current feelings in terms of the challenges that we're all facing, perhaps with reference, Chris. First of all, to the situation, where are we today in terms of the pressures on the dairy industry, in terms of trying to address sustainability? Thanks, Brian, and thanks for the opportunity to participate in this discussion today. It's much appreciated and I'm very much looking forward to it. I think, you know, there are a number of challenges that are animal production industries face globally, really, not just here in the UK but globally and especially. I think it's important to remember that there are some real challenges in the Global South and some of our developing countries. But here in the UK, I think there's been well, from my perspective, I think there's been a real sea change in the attitude of the industry towards some of these challenges. And one of the big challenges as we're here discussing today is sustainability. And there are a number of issues around sustainability, but a major focus has been on the carbon footprint of our animal production systems. And, you know, there are other issues as well in terms of environmental impact and social issues. But really the carbon footprint has been really important. And our government here in the UK and I know it's true in other countries as well, has made a commitment to achieving net zero in terms of our production here in the UK. And the stated intent is that we'll have a net zero agriculture by 2050. And that's a major challenge for our dairy industry. I think part of that challenge is a lot of the focus is on methane emission. Ruminants produce methane. It's an important part of their digestive processes. And but methane is a fairly potent greenhouse gas. And I think the real change I noticed in terms of attitudes was after Cop 26, which was held here in the UK, and there was a commitment made by a number of countries to reduce methane emission by 30% in a relatively short time frame. So there's been a lot of focus on feed additives as a potential mechanism or feed methane suppressing feed products. I believe they're going to be called as a viable option for the industry to help reduce its carbon footprint. And there's a stated intent by DEFRA here in the UK that there will be a focus on inclusion of feed additives in the industry to reduce methane emission. There are lots of other issues. Of course, and I'll just touch on nitrous oxide emissions in terms of our nitrous oxide inventory here in the UK, agriculture is by far the biggest emitter of nitrous oxide. It's a very potent greenhouse gas, has a very long half life. It's associated with fertilizer use and it's also associated with manure and slurry. And depending on how we manage that manure or slurry on our farmland, we can have a substantial nitrous oxide emission. So there's a lot of focus on production systems that rely less on nitrogen fertilizer through the use of legumes. And I think that's an important way of helping reduce our greenhouse gas emissions associated with livestock production, because forage production is really important for dairy and there are emissions associated with the use of nitrogen fertilizer, especially artificial nitrogen fertilizer. Initial thoughts from me. Chris, do you see some particular pressures on what they call old pasture systems that are particularly prevalent in Ireland? For example, I've heard some rumors that, you know, they might be particularly under pressure. The Irish dairy business? Yeah, there is. That's a good point, Brian. There there was a lot of press around a statement by the Irish government that they were considering a cull of dairy cows in Ireland. I think it was something like 200,000 over the course of 3 or 4 years or three years I think it was as, in a way it was suggested as a possible route for reducing the greenhouse gas emissions associated with dairy production, partly through because of their methane emissions, but it's also associated with their nitrogen derogation. And in Ireland and the fact that they rely a lot on spring production of milk using grazed grass and grass production is benefits in that country from the use of nitrogen fertilizer. So there again like in this country there's a move towards more use of mixed grass and legume or mixed clover and grass pastures for production as a way of reducing the need for haber-bosch produced nitrogen fertilizer. Thanks, Chris, for these words of introduction. Laurent, perhaps you could say a word also and perhaps the French situation, but particularly, you know, with your consultancy in some of the more developing countries. I mean, how were they viewing sustainability? Perhaps they have a different view compared to what I call the more a developed mature nations in terms of dairy husbandry and nutrition. Hello Brian and Chris. So first of all, thank you for having me on this webinar, so I'll try to answer your question. Of course, France is part of Europe, part of a world where it is easy to produce and where sustainability problems are in the mind of governments, of consumers. The people are thinking about sustainability, but they are still looking on their money. And when you move to less developed countries. I was in India and in Morocco a few months ago and there the question is how can we produce? And they have heard about sustainability, but really they don't care. At the farmer level, at the dairies level, they just want to produce. And in a way it's evident. But if they increase their production per cow, they will also have a good impact on the sustainability. But without wishing it simply, to come back in France, there is no mandatory legislation, saying that you have to decrease your number of cows or to decrease the methane emission. Some commercial company have set up a system where they prove that they will decrease their methane emission. And commercially speaking, they are helped with this kind of mention on the level that the only way the real sustainability comes to the consumer right now, it's a question of marketing and not a real, sensibility would say. Thanks, Laurent. One point already I think that you brought up that sometimes we don't recognize in the industry is that, you know, high performance is an avenue in itself towards the goals of sustainability because You need less cows to produce the same amount of milk. Therefore, if methane is primarily an individual animal challenge and we will improve that and think you'll come back later on and give some indication of what that means in terms of, you know, carbon footprint per kilogram of milk, etc. So I think that's an excellent first point. Just to come back on, you know, this whole question of, you know, methane mitigation, I think it has got a lot of press, as you said, Laurent and Chris, you know, in the sense that's what people have latched on to. But thought in the slide that's up on the screen, you know, it's I think even recognizes that there's it's not just a meeting mitigation challenge that we have. It's a whole feed optimization challenge we have. And, you know, and when you look at it, you know, the impact we could have. And in addition to reducing the carbon footprint of methane by up to 30%, as you indicated, Chris, is probably we could do the same again by on the optimization of feed, particularly the nitrogen side of the equation, which comes back to a little bit the objective of the rest of the seminar is to dig more deeply into what can be done in terms of nitrogen economy in our rations without losing performance with the perhaps the advantage that we now know that amino acid balancing can can bring to to performance, not only performance of dairy cows, but also to limiting nitrogen, nitrogen inputs. More a statement. But if either of you want to make an additional comment, please go ahead. Yes. Just to say that the good news is even if you work on the enteric fermentation mitigation, you still have the possibility to work Also on feed optimization, it doesn't interact and so you have the possibility to act both way on the same aim on the same goal. So we have to work on both enteric mitigate fermentation. Methane is not everything. Optimization of the feed or the feed production is not alone. Again, we have to work together and you can change also your and you're right Brian, moving to this slide, we have to think at all the steps of the production and for the benefit of everyone of every level of our industry and working on methane mitigation, working on formulation, whatever amino acid or energy it is, you will have a better result working with all the systems. And if I could come in, Brian, just to agree totally with what's been said, I like to say these days I'm becoming an old person and the older I get, the more I go from looking at what goes into and comes out of a cow. And this slide, I think really represents this. And that's everything that goes into a cow and everything that comes out of a cow. I've spent my career studying that. The milk, the manure, the gases, the methane. but now we look more and more and increasingly, in a multidisciplinary approach to what goes into and comes out of a production system. And I really do think we need to look at these issues on a systems basis. You know, when I mentioned that the industry has really taken on board the need to be more sustainable, I think that's reflected in a lot of our producer organizations, a lot of the commercial companies that are buying milk and processing it are making commitments that they want their farmers to be more sustainable. And our farmers here in the UK are have very much taken this on. They're not denying, you know, that there's a methane production by their cows. They're looking for. They want solutions. They want they want technology and management approaches to be able to be more sustainable. They believe they are sustainable already and they want to be more sustainable. And a good example would be, you know, one of our major milk processors here in Europe, they have a number of strategies that they're putting forward for their producers, not just methane suppressing additives, not just improving protein efficiency, but nitrogen fertilizer use, soil, carbon sequestration, etcetera, etcetera. So really a multidisciplinary, multifaceted approach to being more sustainable. Yes. And on this slide, you think as we lead in to perhaps focus more on the nitrogen part per se, you know, you indicate that now, currently only about 25% of the intake, the nitrogen intake of a dairy cow actually gets converted to something that is useful, you know, in terms of edible protein. And I think, again, you've recently completed some studies where, you know, to look at because it would make a big difference to increase that 25% to something close to the ideal of 40% would be a big, big relative relative improvement and would go a long way to, you know, to mitigate some of the challenges we have in terms of environmental impact and carbon footprint. Would you walk us through a little bit the study you did over three years to look at this? And what were your the your takeaway messages from that study? Yeah, I'd be happy to. Brian, could I just make a couple of points on the previous slide, if that's okay. Sure, Go ahead. Yeah. I mean, as you pointed out, I mean, the average there is 25% use of intake nitrogen for milk production or body retention. But, you know, as we know, that varies quite substantially and can be much lower, especially in some of those spring calving block calving sort of grazing herds where the nitrogen concentration of that grazed grass can be quite high. So the theoretical idea some years ago, Jan Dijkstra, as part of a collaborative paper we wrote, calculated based on what we knew about biological efficiencies of all the steps in the process of converting feed protein into milk protein. We came up with an estimate about 43% as an ideal for a cow producing about 40l of milk with a standardized protein and fat concentration. But and it would make a huge difference if we could achieve that. This slide also shows the point about the inputs of nitrogen fertilizer into the system and the potential benefits of using fixation by legumes. Haber-bosch produce nitrogen fertilizer that consumes a lot of energy. And so there's a substantial carbon footprint just for the production of the fertilizer. And then there are losses of nitrate and nitrous oxide to the environment when we use the fertilizer. So we can make a real benefit through the use of clovers and some of our mixed species swards for forage production. But as you say, a big part of this is, is that inefficiency within the cow. And, and yes, Brian, if you go on to the next slide, we did conduct this long term study for for DEFRA here in the UK, which was looking at the potential impacts of, of lowering dietary crude protein for, for lactating dairy cows. And this was partly driven by a previous study we run where we had fed cows lower protein diets that were balanced for metabolizable protein and methionine lysine and in that case using some protected protein sources. And the cows did really well on the lower protein diets. But we were it was a study conducted using a changeover design where the cows were on the diet for about a month and then they changed to another diet. And we wanted to look at the longer term implications. And that led to this long term study. And I think on the next slide I'll give a little bit of the background to it. it was part of a multidisciplinary study, but the work that we did here at Redding, at the Center for Dairy Research was this long term trial over three lactations and we enrolled 215 heifers at first calving onto the study. Originally we were targeting 70 heifers per treatment and because of blocking factors we ended up with 215 in total. So, 72 in some cases, etcetera. But they went on to these diets at the start of the study and then stayed on them on the diets throughout three lactations as long as they survived for three lactations. the diets were formulated at three levels of protein on a crude protein basis that was 14, 16 and 18%, but they were actually formulated on a metabolizable protein basis relative to expected requirement. So the medium diet, we call it the 16% protein diet was formulated to meet requirements for an estimated production of of milk and milk, protein and fat. The low protein diet was formulated to 90% of requirement. And so we didn't try to formulate that low protein requirement, say using supplemental rumen and protected proteins or amino acids to still meet requirement. We intentionally wanted to under feed the protein and it was partly because at the time DEFRA here in the UK was think considering the fact that in future they may have legislation that restricted how much protein could be fed to be more sustainable. And they were concerned about the potential negative impacts on the cows. So that's part of what we were doing. The high protein diet in this case was formulated with 18% crude protein, but it was only at about 104% of metabolizable protein requirements. So it was mostly excess room integratable protein. And yes, the sort of headline figures were that the cows did really well on the study. They there was a lower milk protein and milk yield for the cows fed the low protein diet. So in other words, the cows that were under Fed relative to requirement, the cows fed the high protein diet, the 18% crude protein diet, they actually consume more feed, but they didn't produce more milk than the cows fed at their requirements. So there was no safety factor in here. We often over feed protein to because of an inclusion of a safety factor. So without the safety factor, the cows did really well and by the time we were in their third lactation, the cows that were fed to their requirements for amino acids actually produced more milk than the cows fed the high protein diet. And they did really, really well. We were expecting the cows to produce substantial more milk and less milk, sorry, on the low protein diet than what was observed in our study. That was partly based on some work that had been done previously in Northern Ireland for Ryan Law's dissertation. But when we went back and looked at it, they were formulated to be fed at 90% of their metabolizable protein requirement, and they produced 93% of the protein that the cows on the medium protein diet produced. So the feeding system we use worked reasonably well. So we were really pleased the one negative for the cows that were fed the lower protein diet was that we had lower fertility and so we actually had fewer cows going to the fourth lactation, which was about a third, would have survived to their fourth lactation on the low protein diet. We're on the medium and the high protein diet. About half the cows would have gone on to their fourth lactation. So survival was reduced through effects on fertility and we had more abortions and more embryo loss when they were under Fed protein. But they're otherwise they did really well in terms of nitrogen efficiency, just typical nitrogen efficiency curves, higher yielding cows and early lactation. They're producing more milk, so they're more efficient and the efficiency drops as yield drops. But the cows on that high protein diet had much lower nitrogen efficiency because they were consuming more feed, but they didn't produce more milk and milk protein than the cows on the medium protein diet. So I think overall it just shows that we can feed cows and we could feed, we could formulate diets. And this study, we didn't use any protected amino acids or rumen protected proteins. It was just a substitution of rapeseed meal and soybean meal to achieve these differences. And so we could have fed a lower protein diet, used a bit more precision technologies to formulate the rations. And we I'm sure we could have fed the cows with a lower crude protein level and still achieve that level of milk production. But it did show that the cows did really well without the safety factor. But there is a concern if we get too much below requirements for amino acids. We the cows again were very resilient. They did really well, produced relatively well, but we did have some impacts on fertility. So that's a summary Here we showed we could get over 30% efficiency and not quite yet at the 40%. So that'll perhaps lead into some further discussion. How can we improve further? But I think one thing you also looked at in this study was the the actual variation in the TMR and nitrogen levels. And therefore, I suppose my question to you, if you could have controlled that better, would we would you anticipate to have tightened up? So the performance. And if the answer is maybe yes. Well, how can we manage the nitrogen inputs better? Okay, So yeah i think. For us here at Redding. One of the observations that we found quite revealing. in a number of respects was variation. So first of all, variation in our diet composition. So we were we, you can see we fed these diets over. It was for more than five years running the study and we were feeding these diets and we were sampling them daily. We were sampling sorry, the diet components were being sampled daily and we did a weekly composite and then analyzed that for protein in our own lab using kjeldahl. And we're, you know, we're an experimental facility. We're very good at sampling, forages and diet components, concentrates and consistently analyzed it. And so we were monitoring the crude protein concentrations of our TMRs weekly throughout the course of that study. Now. If we had not done anything, made any changes. This slide shows what TMR crude just crude protein concentrations would have been and you can see how much variation there was and going in. We were worried that there would be variation, especially in our grass silage. The diets were based on maize or corn, silage and grass silage. And we do have quite a bit of variation in our grass silage quality because we have fairly it's a large herd, we have fairly large silage clamps and there are a lot of inputs of grass that go into our grass clamps. Our maize silage is lower in protein, so it's less variable. But we also had variation in our concentrate blend that we were feeding in terms of protein concentration over time. So Brian, what we did was based on a rolling three week average, we then adjusted the crude protein using supplemental soybean meal because mostly we were below in terms of protein concentration. So we did make adjustments. And if you go back and look at our adjusted TMRs, we were much closer, don't have that figure, but we were much closer to our target. But that was through weekly monitoring and think technologies that might enable us to monitor ration components, perhaps handheld. It's something that's used here in this country might be a useful tool. But I also think it's important to remember that cows are relatively resilient to this kind of variation from day to day in diet composition. And some of the work that my colleague at Ohio State, Bill Weis, has done, looking at impacts of variability and also some of the work that's been done where people have intentionally oscillated protein concentration to see if it can make cows more efficient. What those studies have found is that cows tend to produce to the average over time. So the average composition of the diet over time. So we really need to know that average and monitor to make sure we're maintaining that average over time. I think that's most important, Brian. The other source of variation that we observed was variation in individual cow nitrogen efficiency, and that's something we've been following up on since the study was completed. We do think that there is potentially a genetic basis to that nitrogen efficiency variation within individual cows. And then it may be a trait we may be able to select for in future. There is work showing that you can use Mid-infrared spectral analysis to predict nitrogen efficiency of individual cows, which would be a great way of phenotyping cows for genetic selection studies. And so that's really important. But I also think that it's important to remember that nitrogen efficiency of individual cows is correlated with feed efficiency. And part of the reason we had differences in nitrogen efficiency between individual cows was because we had differences in milk protein yield. And so higher yielding cows are more efficient. Cows fed. Lower protein diets that maintain yield are more efficient as well. So there both aspects of nitrogen efficiency that are really important. And so if we if we can improve feed efficiency, it will be associated with an improvement in nitrogen efficiency. There also may be components of nitrogen efficiency that are distinct from pure energy feed efficiency. So I think that's important to remember. So I hope that's answered your question, Brian. So yeah, great answer and I think gives us all a clearer insight into that, Laurent any comments on that or will we move on to your the next area. Perhaps one comment. We are looking at the sustainability, looking at the production during three years. So such research research length is very seldom. So it's very interesting to see that a cow can live with a lower CP diet. But if we think about sustainability, we have to think at all the lifespan of the cow And methane emission is not occurring only during milk production. It is occurring also during the heifer period. So when we talk sustainability, we have to think differently. We have to think. During the whole economic life, but at the beginning. Coming with a newborn calf. So the functional unit is not the milk produce "d" day, but the milk produced during the whole life that the functional unit. What Is a weight of the CO2 of one kilogram of milk, including everything crop production, heifer racing, etcetera, etcetera. So wonderful with a three years study, but we have to think longer. I agree totally Laurent. And can I just say, Brian, one other part of our project, John Mawby at Aberystwyth conducted a similar study, but he started at weaning and he looked at heifer rearing and nitrogen efficiency and heifer rearing and had some really interesting results in terms of feeding lower protein diets to to heifers during the first two years of life and then the effect that had on their milk production once they became adults. And so there was some really good work there. And Laurent is absolutely right. Age at first calving is a really important component of sustainability on our dairy farms. And so couldn't agree with you more. Aging , first calving and what call also agent culling because in terms of its lifetime performance that will also like, the elegant way that Laurent said that but basically you know at the end of the day we ideally would like to present the data in terms of the mitigating or improving carbon footprint per kilogram of milk across the lifetime of the animal, the lifetime performance of the animal. And just one more comment. If you look at the efficiency of the additive, mitigating the methane production, the most powerful one will decrease by half. Half of the production will be decreased. But when you look at the LCA impact of this decrease during milk production, it will be only a 12% decrease of the CO2 value of the milk. If you look at the different publication, you see that it is due to the heifer period, the 40 or 50 decrease of the methane during the milk production will be only 12% as a functional unit milk produce per day of life. So we have doing to be better on the feed side also. And that perhaps a good segue a lot into perhaps the next aspect is no secret to perhaps the audience. Aidsseo has been involved in amino acid balancing of rations or trying to improve that knowledge base for over 30 years now. And we recently put together a summary of all the trials that we've done in this area. And I want to emphasize again of logging longitudinal type studies. We did not include Latin Square or crossover trials, Chris, A little bit for the same reason that perhaps you did. We feel that short term response is somewhat can give false impressions sometimes and therefore we felt better to rely particularly now that we have a large number of longitudinal studies. But it was interesting to find you know, that I mean, obviously there's variation from trial to trial, but there was a consistent positive benefit. And when you amino acid balance rations and what I mean by that for lysine and methionine and you know there was one perhaps relatively new observation was that the effects were as big if not more on milk fat than than they were on milk protein, which again that's an aside and covered in one of our other webinars. You know why that occurs. You know, it's not just. A surprise and no one can explain. We can explain that. But, you know, the improvements on total components were of the order of 150g per day. But the question here for this particular webinar was, I mean, these were mainly trials. Again, yes, we were maybe minimally trying to improve, you know, at a lower nitrogen supply in the rations, but not to any great extent. So these were performance benefits at more typical, protein levels in rations, both in terms of depending on whatever system you use to formulate diets. but I think the question going forward and Laurent you have a lot of experience in this is that can we take the advantages on performance of amino acid balancing keep them and use you know the theory that well if we if we present a better profile of amino acids. In the protein we feed to dairy cows, we should be able also perhaps to drive proteins down to even maybe the levels that Chris, you were of your low crude protein ration in your trial. So perhaps, Laurent, you'd give us a little bit your perspective on what you've seen over time and how you've approached this subject. I often like to remember that a ruminant is a monogastric behind a rumen, and all we knew about monogastric will be good for the intestinal part of the ruminant. And I had during my career to formulate for monogastric and for piglets, for example. And of course, if you want to increase the piglets performances and to decrease the cost of the piglet feed, you have to decrease the CP value. But you can't not do that without thinking amino acid. So that's exactly the same for the ruminant. The idea is to decrease the CP or even the MP values, but balancing. Be sure to balance for a good supply of the essential amino acid and You showed many old studies 30 years ago. They did a field study with a smart mean, so a simple addition of smartamine And it was in 1996. And at that time already we saw a benefit on production, a benefit on health disorders, on production only protein. At that time we didn't look at fat, so everything was clear. 30 years ago. Ten years ago, we began to have a very expensive soybean. So the idea was to decrease the price of our feed concentrates by decreasing the CP value. And as I said, farmers are very reluctant to changes. So we had to explain easily. And if you can move to the former slide that we use these kind of buckets. So it is very common to use the bucket in order to explain amino acid. But in my case, I made two buckets. Now the one classical on the left and amino acid balance on the right. So you decrease the MP or CP of the diet, but you maintain both limiting amino acid methionine and lysine. And again, if we want to implement this kind of formulation, we have to explain it simply. And pedagogical tools are very useful in order to make the people, whatever they are, understand what we want to know. Science is there, there is no problem. We can decrease the CP value, but we have to explain the feed formulator. We have to explain the farmer that they will have some benefit at their own level. And if we want to take the sustainability into account, that is more complicated because right now in Europe there is no Economical interest in it, except some commercial advantages. But your milk will not be paid more or it will cost what you will be paying more. So right now it's difficult. And for the formulator also, it's very complicated because he has to have in this computer many, many data coming from everywhere. And we have also to choose one functional unit in order to be able to compare on the same basis. So right now, this functional unit is standard functional unit. It doesn't exist. We say one kilo of milk, but is it a standard milk? What kind of standardization of milk, etcetera, etcetera. And the value in North America is not the same in South America, not the same in Europe. So it's real complicated. So that's one of the problems we will face. Explain and make understand. But again, if we increase the production, if we increase the nitrogen efficiency, it will be good for the planet. So no matter. So again, at what level can we go? How low can we go? My first answer will be we have to move slowly because we saw that the result of the CP even in a research center comes to a large variation. So at the farm level. Move slowly and look at the results and then move a little step lower and you will see what will come in the milk tank. But yes. In a publication I made just ten years ago. We decrease our average CP value the diet by half a point. But in France, using the protected soybean or the protected meals, the average CP is already below 16. So decreasing by half a point is already a good result. So we moved from 15.5 to 15 and with very good results exactly what science predicted with a production, a higher production of half a liter, more protein, more fat. We didn't we we have not been able to see any results on fertility in that case. But no change, no detrimental effect at all. Only economical effect. And that was our goal, to make our customer happy with the efficiency of our feed and to earn some more money Sustainability was an additional benefit. Thanks, Laurent. Perhaps as before we finish our webinar today, I'd like you just to walk us through the recent SOS protein study and briefly, but particularly how you then took the results of that to, let's say, build some scenarios on how far could you go, not just on protein levels, but in terms of, you know, if the formulation and target in the future becomes dominated by sustainability factors, how far can you go to reduce the carbon footprint? So would you briefly go through that study and what and explain the slide that is up just now and what and what it can mean for the future? Okay. So this study was conducted by INRAE in Brittany four years ago. And the idea was to improve the protein autonomy of this region. And they decided to propose to commercial herds, a very simple trial, easy to implement at the farm level, decreasing the soybean meal distributed every day by £1 and increasing the energy to be at the same level with £1 of farmed cereal and complementing with the protected amino acid. So the initial diet there is the average of five farms of the ingredients of five farms. So you see that the nitrogen efficiency was already high, 33% because of the high level of production of these commercial oil, more than 35kg as an average. And if you see that value of the diet CO2 equivalent per kg of milk was one half of KG. So that's only the diet part of the milk value. they made a substitution. So the third column is the trial itself and changing soybean to farm cereal. Of course you decrease the CO2 value of your diet and that's a 10% decrease. If you had only add the amino acid, you will have increased production, but you will have also you have add the value of your amino acid and the improvement in the diet CO2 equivalent will be less One zero -1%. But the idea then is what if you optimize only an amino acid? Not a simple substitution as they did to be easy to implement, but just formulate Based on the Classical constraints of energy, minerals, vitamins, etcetera, but changing the MP requirements into lysine and methionine requirements only. And so. With the same ingredients. You may decrease the CO2 value of the diet by one third. -34% with a better production and the production was increased using the Meta analysis made by the result Brian just showed us in each time you increase lysine and methionine, you see an increase in production. So these equation were put into the prediction model and the value there was really interesting. But if you want to go further. And put some constraint on the CO2 value of your diet. Then you can reach a real low value of the CO2 equivalent of the diet. But you change the composition and then you decrease the nitrogen efficiency and you have to increase also the CP value of your diet in order to choose very poor CO2 ingredients, but to decrease the efficiency at the cows level. So this column optimize without constraint is the one choose all the time formulating for amino acid and changing no constraint on the energy or minerals part of the diet and trying to choose the byproducts or the wet products or the local products in order to decrease this diet value. But more of that. That's again during the production that the production of the farm at the day they eat these diet. But as we know, when you give a well balanced diet to an animal, you've got other benefit than only production. A health again, repro, And I tried to put this into a model propose to the blonk company to make sure that the prediction was good and then you have a LCA showing that formulating on the amino acid part of the diet you will not only decrease the CO2 value of the diet, but you will decrease the CO2 value of the milk produced during all the life of your herd. Of course there are many other parameters herd management, heat stress, heifer racing. ET cetera. ET cetera. But culminating with amino acid, you have a real initial benefit for the production, for the sustainability, but also at the lifespan aspect of the production also. So that's the way I tried to formulate when I explain sustainability, not only the diet proposed, but also the lifespan. And just a data. In France, the average lactation are 2.3. There are only 2.3 lactation per cow. I think in the US it's about the same. But at the same moment. The the oldest cow produce still producing in the US is 14 years. So there is a huge gap between the average of 2.3 and the possibility of producing economically viable eating. So we have to think longer life with a better balanced diet. I appreciate that Laurent and I sort of pulled up the somewhat the last slide here because I think it encompasses a lot of the things you've touched on, some in more detail than others. But I think all that are important for thinking through what the vision can be to improve the sustainability footprint or carbon footprint of our dairies. Chris perhaps you'd like to emphasize the points you think are most important. You know, going forward where what we know what can be done already and maybe what we still need to work on to see to improve further. Yeah. Thanks, Brian, and thanks, Laurent. Really enjoyed the discussion today. I mean, still come back to what we said at the beginning. And what Laurent has really emphasized is that we need to look at things on a systems basis and we look at need to, you know, look at And have access to verifiable figures in terms of the carbon footprints of some of our feed ingredients, etcetera, etcetera. I think a big question certainly here in the UK where a lot of our ruminant livestock production is grass based, we need to have some really good estimates of soil carbon sequestration in our grassland systems and how we fit those into to our life cycle analyses. That's really important. I don't know. I think one thing we haven't mentioned today is, which is part of this as well is transition management. Brian and the potential role of precision management during transition from late gestation to early lactation and some of the carryover effects that we might be able to achieve through using individual amino acids, perhaps as as metabolic signals for switching on protein synthesis in the cow and improving immune function and health because the carryover effects there could be quite substantial. So that's something I've got a personal interest in, so I'll throw that in. So but those are just a few thoughts from me. Well, thanks, Chris. In fact, you sort of have to insist to the audience that you did not set you up to say that. But, you know, just to remind the audience that a lot of the transition, certainly the transition area and the reproduction area have been covered to some extent in previous webinars. I think number two and number three. And so I'd encourage audience who are interested to know more about, you know, how amino acids can enhance getting cows off to a good start to lactation and what are the specific roles of lysine particular methionine you know in that pre fresh and post fresh period to minimize metabolic disorders and therefore set the cows up better for a better reproduction all leads to you know this whole question well we want to keep cows around longer. The cow can certainly stay around longer if we feed her right to stay around longer and still get improved performance. So thank you, Chris, for the setting up that more a statement, I think than any than anything else. Before maybe give a last word to Laurent. I'd just like to also emphasize, you know, here and in terms of the vision for sustainability that, you know, sustainability is not just what I call the environment side or the carbon footprint side. It's also. And very important that this is for dairying itself to be sustainable as a profitable entity. And that's, you know, it's bringing that all together. I think we had a slide earlier where it was very important that whatever we're doing, we're trying to continue to make money at all levels while respecting these new constraints we will have in terms of the way that we actually do dairying today. Any last comment, Laurent? Perhaps Yes. A few words. Science is going on. We have to rely on science. But in order to take benefit of this science, we have to implement it properly on the farm. That means we have to know exactly what is the dry matter intake? What is the CP value of our ingredients? What is the dry matter of our feed? So very practical data, very basic. And if everybody make some effort in order to have the real values, then the production will increase because some consultant, because some adviser will come and will tell the science. But at the farm level, there is a lot to do. There are a lot of pedagogy to be done at this level. Measurement is the basis of everything. Well, thank you both. I really enjoyed this conversation we've had today. Hopefully we may be able to do that some other time in the future. But I can't thank you both enough. I'd just like to remind the audience that this is the fifth of our six part series on amino acid balancing and effects on various aspects of performance. Transition, Cow Health Reproduction. And etcetera. And just to set you up, next month, we will have the final webinar in this series which will focus on a formulation specifically and particularly with respect to formulating on amino acids through the Cornell, the present Cornell model and what's envisioned to be the next version. And that will be given by Dr. Mike Van Amburg of Cornell University. But again, big thanks to you both. And again, we'll sign off now. Thank you so much. Thank you.