This Real Science Exchange podcast episode was recorded during a webinar from Balchem’s Real Science Lecture Series. You can find it at balchem.com/realscience.
This Real Science Exchange podcast episode was recorded during a webinar from Balchem’s Real Science Lecture Series. You can find it at balchem.com/realscience.
Dr. Santos begins with a timeline of events that occur during the cow’s transition from the dry period to her exit from the fresh pen. He suggests that cows should be dried off at around 230 days of gestation, then moved to a closeup group at 250-255 days gestation which is around three to three-and-a-half weeks before calving. Dr. Santos recommends keeping multiparous cows separate from primiparous cows and feeding to minimize metabolic disorders in early lactation. After calving, cow health needs to be monitored for early detection and treatment of disease. In addition, diets that do not limit voluntary dry matter intake should be fed. During the early postpartum period, controlling excessive weight loss and lipid mobilization is the goal. (00:27)
What is the association between time spent in the closeup pen and disease? Research shows that around three to four weeks in the prepartum group is associated with the lowest risk of morbidity, maximum milk yield and highest pregnancy rates. How does a change in body condition during the first 65 days in milk impact cyclicity? How does 90-day milk yield impact cyclicity? Cows that lose one or more units of condition are less likely to be cyclic at the end of the voluntary waiting period. There is a small statically positive association between milk yield and cyclicity. Dr. Santos’ first take-home message is to avoid excessive body condition loss after calving. Cows should lose no more than 0.5 body condition units from the week before calving to the first AI. This can be accomplished by minimizing over-conditioned cows at dry-off and reducing the risk of disease in early lactation. (6:13)
What about feed efficiency? Dr. Santos describes experiments comparing the 25% most efficient to the 25% least efficient cows. All cows produced the same amount of energy-corrected milk, but the most efficient cows ate four kilograms less feed each day. The risk of morbidity and the culling rate was the same for both groups, as was reproductive performance. Dr. Santos suggests we should not be afraid of selecting for feed efficiency while still optimizing intake in early lactation. (18:23)
Morbidity negatively impacts intake in early lactation. Around one-third of cows are affected by disease in the first three weeks of lactation and almost 80% of the first disease diagnoses occur during the first three weeks postpartum. The earlier in lactation disease occurs, the longer the legacy effects from that disease can impact cow health and performance. Dr. Santos describes an experiment in beef cattle evaluating how an inflammatory response impacts nutrient partitioning away from performance. Early lactation morbidity not only makes a cow not want to eat, it also may shift nutrients away from production toward survival, resulting in fewer nutrients available for milk production and reproduction. Dr. Santos describes a series of experiments evaluating the impact of early lactation disease diagnosis on reproductive performance. Dr. Santos’ second take-home message is to stimulate dry matter intake and minimize disease in the early lactation period. (22:21)
How can we formulate diets that will improve reproduction? First, we should formulate diets that reduce the risk of disease. Then we should incorporate nutrients that are known to improve reproduction in cows. Dr. Santos describes how supplementation with rumen-protected choline decreases triglyceride accumulation in the liver and improves milk yield. He also details the mechanisms of using acidogenic diets to reduce hypocalcemia. He recommends not using these diets for heifers and feeding them for around 21 days to cows rather than the entire dry period. Dr. Santos feels that forage quality has been neglected in the transition period and details how improved fiber digestibility during the transition period can have longer-term impacts. Lastly, he recommends feeding 1-1.5% supplemental fat in early lactation diets for improved reproduction and milk yield without negative impacts on body condition. In closing, Dr. Santos presents a summary of diet formulation recommendations for transition cows. (34:13)
Dr. Santos leads an engaged question-and-answer session with the webinar audience. (51:11)
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Moderator (00:00:00):
The following podcast is taken from a webinar presented by Dr. Jose Santos from the University of Florida, titled Transitioning to Success, the intersection between Nutrition, health, and Reproduction. To view the full webinar and access the slides referenced during this podcast, visit Balchem.com/real science and use the search bar to jump down to this webinar presented on November 2nd, 2022.
Dr. Jose Santos (00:00:27):
It's a pleasure to be here and for the next 45 minutes, I hope I will spend a little bit of time with you exchanging some ideas related to the transition period and how that may impact the success of the subsequent lactation. And then I will touch on a few aspects and how nutrition may interact with that. So this is how I typically see the transition from the dry period to the point in which the cow leaves the fresh pan. So if we think about the activities that we typically perform on dairy farms first thing we plan a dry off, which typically takes place based on when the cow became pregnant. So I'll make the case that cow should be dried off at about 230 days of gestation. And at this stage, we hope that cows have proper body condition.
Dr. Jose Santos (00:01:21):
And what I mean by that is that they're neither over condition or they are extremely emaciated. So in the one to five scale, we hope cows would be here with a body condition score between 2 75 and 3.25. And here we need to have a plan to control mastitis, to control lameness, to control infectious disease. And we typically would feed a diet to avoid over or under consumption of nutrients. Okay? So we don't want this cow to gain body fat neither. We want the cow to lose body weight, okay? Obviously, she's gonna be growing a calf and there will be weight gain, but we don't want her to deposit excessive amounts of body tissue that is not just calf and uterine weight. And then the would be moved to a closeup group when she is about 250 to 255 days of gestation, approximately three to three and a half weeks before the expect cabin day, which for the hosting breed today, gestation length is approximately two hundred and seventy five, two hundred seventy six days.
Dr. Jose Santos (00:02:25):
Here. Hopefully we'll be able to properly group cows. And what I mean by that is to have newly per separate from Pero scales, and I'll make the two points that are important relative to that. We'll continue with our health program. And here the main goal is to feed diets to minimize metabolic disorders in early lactation, because these problems here will set the cow back for a successful lactation, whether we think about survival, milk production, and reproduction. And then once this cow gets into the Kevin time, we hope that she'll be in a comfortable place and will be assisted by trained personnel that knows when to interview, when, when to intervene, at the same time the minimize intervention, and they also reduce KEV related disorders. So here is a trade off between having reduced number of steel births at the same time that we don't cause excessive damage to the cow because of early assistance, particularly for newly paired cows that perhaps are delivering a mayo calf that are the ones that are gonna have a greater challenge at this point.
Dr. Jose Santos (00:03:35):
Once this cow moves to the early postpartum period, we need a plan to monitor health for early diagnosis of disease, and we need treatments in therapy that are science-based at this point. So here we have to feed diets that do not limit voluntary dry matter intake. So we wanna feed diets that we know that cow will be able to eat as much as she wants. And the goal here is to control excessive weight loss in cows, in particular excessive lipo mobilization, which we can use as a thermometer subclinical ketosis. So we can use this just to guide us whether these cows are losing excessive amounts of weight or not. And the goal here is to minimize that. One aspect of controlling excessive body tissue loss is to have cows that have a proper body condition, and we have at the same time, less disease.
Dr. Jose Santos (00:04:28):
Then once these cows graduates from this fresh pen, which can last up to four weeks, and some farms may be only two weeks, and some farms may be a little longer depend upon the Calvin flow of cows, then she moves to a high group in which we're gonna feed diets that maximize milk production and also facilitates the recovery of body condition. So those are sort of key goals of the transition period and key tasks that we typically implement in most farms. All of this we wanna do with proper cow comfort and heat abatement
Balchem (00:05:10):
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Dr. Jose Santos (00:06:13):
So let's look at the importance of cows spending time in this transition pain. So a few years ago, Achilles and NATO PhD student now working with Mark Animal Health he collect data from two herds over three calendar years, and we collect over 18,000 cow records from those farms that we monitored disease. And the disease we were interested were those who listed here having problems such as dystocia and stillbirths, retained fetal membranes, metritis, respiratory disease, mastitis, displaced double mason, other digestive problems, and whether the cow died or not. And this all in the first two months of lactation. What we want to investigate and, and, and ask the question is, what is the association between time spent in the closeup group and the risk of this disease? For the sake of time, I'm gonna show you the risk of morbidity, which is one or more of these events.
Dr. Jose Santos (00:07:08):
What happens to milk production and what happens to reproduction? So here is the risk of morbidity in the first two months of lactation for cows that are starting their second or greater lactation and cows, starting their first lactation the nu cows. And we can see this days in postpartum group quadratic association with risk of morbidity. And what I mean by this is that the risk decreases ascal spend more time in the prepartum group, and then they in the risk increases as they spend excessive amount of time in the Prepartum group. So there seems to be the switch spot here, which is about three to four weeks in which cows have the less risk of developing disease in early lactation. And if we have less disease, we expect to have greater milk production. So this is the cumulative milk yield in 305 days, divide by 305 days, meaning that if a cow died early or if she was sold, she will contribute with milk for only the period that she survived.
Dr. Jose Santos (00:08:15):
Okay, so this is accounting for deaths and calling. And you can see that cows that spend about three to four weeks in the transition group in the Prepartum group had the maximum meal killed. And this should also reflect and improve reproduction, which is exactly what we see here. The proportion of cows that became pregnant by 300 days, and again, this accounts for cows that died, were sold and never became pregnant because the producers decide to eliminate those cows. And we can see that the highest or the largest proportion of pregnancy happen when cows spend those three to four weeks in the prepartum period. So if we wanna benefit from the things that we apply in the transition group, cows need to spend a minimum amount of time there. Now, let's just look at this typical dairy cow on a farm. So this is your typical holing cow, okay?
Dr. Jose Santos (00:09:10):
That averages peak milk yield that approximately 45 kilograms per day. So obviously many cows produce a lot more than that. But if you take a think of our average cow today, she requires this many mega calories of metabolizable energy for her maintenance. And then she needs this many mega calories of metabolizable energy for milk production. So to produce 45 kilograms of milk, which every cow will do at some point, or most of them will do at some point, she has to consume 70 mega calories of metabolized by energy per day. This means that if I divide this 70 by the maintenance, this cow is working at about four and a half times her maintenance needs. Now, if we get extremes of the population such as the current world record, this cow peaked at 123 kilograms of milk. And there are probably many cows that get close to this one, perhaps not 123, but many cows today produce 70, 80, 90 kilos at peak.
Dr. Jose Santos (00:10:14):
So this cow is probably a little larger than this one, so she requires a little more, I'm assuming, for her maintenance. I don't have her body weight, but for synthes of milk, she requires a lot more. So this is a cow that's working almost nine and a half times her maintenance needs. So it's obvious that cows like this, and as we have more and more of those, they're more sensitive to alterations and stress and stressors that can affect how nutrients become available to them, and that can affect long-term reproduction. So let's just look at this data here. These are data that we collect from a little over 5,000 cows in which we took blood samples sequentially before the first insemination to determine whether these cows were cyclic or not. And then we asked the question, is there any association between the change in body condition in the first 65 days in milk and the probability of cyclicity or the milk yield in the first 90 days in milk in the probability of cyclicity?
Dr. Jose Santos (00:11:23):
So you can see clearly here the cows that lose excessive amounts of body condition one unit or more in the one to five scale, a smaller proportion of them is cyclic by the end of the voluntary waiting period. So 58 versus 81%. So losing too much tissue is not good for resumption of cyclicity. Now, milk production, if anything, has a positive association with cyclicity. In other words, cows that are more productive. And this is the quartile within Prius and multis that produce on average 50 kilograms per day in the first three months of lactation. And this is the quartile that produce only 32 kilograms per day. You can see that that numerically the changes are small, but statistically it's a positive association. So we get more cyclic cows in those that produce more mule. Now let's look at pregnancy. At first, ai, we see the same association, a smaller proportion of pregnant cows when they lose too much body tissue.
Dr. Jose Santos (00:12:23):
More pregnant cows when these cows suffer. No change in body condition in early lactation. And if we look at milk yield, we see no relationship whatsoever. So my point here is that maintaining body tissue in early lactation or not mobilizing excessive amounts is very important. So how do we do this? We minimize the proportion of cows are over condition once they go dry, and we reduce the risk of disease in early lactation. So why am I telling you this? So let's just look at some mechanistic data here. This is a molecule of glucose, which is needed by many tissues, including the memory gland, but also the central nervous system. And we know that the central nervous system, particularly the hypothalamus is important to control reproductive cycles. This is another molecule that has a small alteration. You can see a replacement of this hydroxy group by a hydrogen in this carbon here.
Dr. Jose Santos (00:13:25):
And this small change here is enough to prevent the molecule to enter the glycolytic cycle. So it blocks glycolysis, meaning that it blocks the supply of energy for the cell, and the cells that surround the neurons, they require glucose. So what these people here did, they infused either saline in the fourth ventricle of the brain of use, or they infused this molecule to the oxy glucose that we know blocks the supply of a TP for the cells. And you can see that when saline was infused, these animals continue to have pulsatility of luteinizing hormone. And this hormone is very important to maintain follicle development, to induce ovulation. Whereas when they infuse to the oxy glucose, they completely ablated the pulsatility of LH by the pituitary gland. So this is telling us that probably they block the release of gonadotropin releasing hormone by blocking the supply of energy for those cells.
Dr. Jose Santos (00:14:32):
So you can think that cows that lose too much weight, or cows that don't eat very well in early lactation, they're gonna have reduced concentrations of glucose because the memory gland now is taking up most of it. And in those case, reproduction will be set as a secondary plan. And obviously extended extensive delay of cyclicity, which will happen in animals that have this, will set this cow back for poor reproduction. So let's think of this mechanistic approach. What we want is for cows at the end of the voluntary waiting period to behave like this one here, who is displaying signs of Astros. So this will happen if her brain receives sufficient signals, including what I call oxidizable metabolic fuel. So it can generate energy in addition to other endocrine signals. When this happens, we have signals for the pituitary gland to release hormones such as follicle stimulating hormone and luteinizing hormone.
Dr. Jose Santos (00:15:36):
And this will maintain follicle development in the ovaries. Eventually, this follicles are, one of them will produce sufficient estradiol that will signals the hypos and the pituitary to have a surge of hormones that induces ovulation. And typically ovulation follows this steroid dependent reproductive behavior such as asterisk. However, when cows lose excessive amounts of weight, either because they don't eat very well, they have disease or other factors, okay, this system is inhibited now. So now we don't have, we don't have the normal pattern of LH release that supports follicle development. Therefore, this animal does not displace signs of Astros. Consequently, she has delayed ovulation. She's the typical a ovular cow, and those cows have reduced reproduction, as I just showed you. So we wanna minimize the proportion of cows that suffer from this problem. Now, we know that energy balance or nutritional balance is an important drive for reproductive success.
Dr. Jose Santos (00:16:46):
And if that's the case, we should focus on what affect nutritional balance and what affects nutritional balance is dry matter intake. So here I have energy balance calculations for the first 60 days in milk out of 160 cows in which we had daily milk killed daily dry matter intake and daily milk composition and body weight. And you can see that there is a linear and strong relationship between energy intake, in other words, dry matter intake and energy balance. Whereas if we look at energy secreted in milk, in other words, milk yield and energy balance, the relationship is quite weak. It is negative, okay? As energy secreting milk increases energy, balance becomes smaller, but that relationship is quite weak. So we should focus on stimulating cows to eat in early lactation. So my first take home message is avoid excessive body condition loss with the unsettled lactation cows should lose no more than 0.5 units.
Dr. Jose Santos (00:17:51):
And for that we should have cows and heifers that do not calve over condition. We want to have more cows calving like this, that we see a u and a V here between the e the head of the femur and the isum, and we want to see almost none cows, none of the cows would have a flat back or that have excessive fat in the ligaments either in the tail or here in the ium. So this poses a question, but what about feed efficiency? Now, now we have markers to select cows for reduced feeding intake for a given amount of milk production, which is what you have available as feed seed, as new a new trait that's available for the hosting breed. So let me show you some data that we generated a few years ago in which we look at the most efficient cows and the least efficient cows in experiments that we conducted.
Dr. Jose Santos (00:18:51):
These cows here produce exactly the same amount of energy, correct milk, but they ate four kilograms less, okay? Four kilograms less, 25 kilograms of dry matter per day, versus 21 kilograms of dry matter per day in the first 15 weeks of lactation with exactly the same amount of energy corrected milk. So how can this be possible? Obviously, these cows here are different than these cows. We don't necessarily understand why they are that different or what makes that difference, but we know that they are different because they're able to produce the same amount of milk with a lot less fee. So people would probably ask, well, there might be negative consequences to that. So let's look at some data here. So we looked at the risk of developing disease in the first 90 days in milk, and I'm only gonna show you the 25 percentile most efficient cows, those that eat less for the amount of milk produced and the least efficient cows, the 25th percentile least efficient cows.
Dr. Jose Santos (00:19:55):
There's about a hundred cows in each of those two groups in the two extremes of the population here. So you can see that the risk of retained placenta, metritis, mastitis, displaced double mason, so on so forth, they do not change. In fact, the risk of morbidity in the first 90 days in milk is exactly the same. Okay? About 40%, the proportion of cows that left the herd by 300 days in milk, either by calling or sale being sold, it's exactly the same, about 10%. Well, you might ask, maybe reproduction will suffer. So let me show you another piece of data from the same dataset. Now, I have here about 850 cows that we have daily dry matter intake, and we calculate what's called residual feed intake. So these are the most efficient cows, these are the least efficient cows. You can see a difference of almost four kilograms of dry matter intake between them.
Dr. Jose Santos (00:20:53):
This cows ate 1.9 kilograms. Less than expect this cows ate 1.98 kilograms more than expected. They had exactly the same energy corrected milk production in the first 15 weeks of lactation. So if you look at the proportion of cows that became do not inseminate, we see no difference here. And now let's look at some of the important traits for reproduction. All of these values are based on a diagnosis of pregnancy performed 74 days after ai. So this accounts for all the losses of pregnancy during early gestation. You can see that insemination rate did not change about 67% between the two extremes. But pregnancy per AI was actually greater in the more efficient counts, and this result in a greater pregnancy rate, okay, in the more efficient cows. And with that, a larger proportion of those cows were pregnant by 300 days compared to the least efficient cows.
Dr. Jose Santos (00:21:54):
And this is quite puzzling. How can these cows eat four kilograms of dry matter per day less than this cows, they have exactly the same energy correct meal, and if anything, their reproduction is the same or a little bit better. So I think at this point, we shouldn't be afraid of selecting for feed efficiency, although we should optimize intake in early lactation. Now, one thing that affects intake in early lactation is morbidity. Because most disease in cattle or in dairy cows affect cows in the first 45 to 60 days of gestation. So let me show you some data here of disease that affect the reproductive tract. This is an Instagram of when Metritis is diagnosed, and this data was put together by a colleague, Dr. Klip Galvan, here at the University of Florida. You can see that we have the highest prevalence of metritis right here at the end of the first week postpartum.
Dr. Jose Santos (00:22:56):
Now, if we look at this data from Eduardo Ribo from University of Guelph, you can see that of the disease that do not affect the uterus, still most of them affect cows in the first three weeks of lactation. So these are the first three weeks of lactation. And the cystogram short shows the skewed distribution because the risk of disease decreases lactation progress in most dairy farm. So if I overlay one figure with the otter, what I come up with is that about a third of the cows are effect by disease in the first three weeks of lactation. And almost 80% of the first disease diagnosis occurs within the first three weeks postpartum. And obviously the earlier disease happen, the longer the leg, the potential legacy effect of that disease event In the lactation, having a disease event at 20 weeks postpartum, it's a lot less costly than having a disease event in the first three weeks of lactation, just because this year can affect the remainder of the lactation.
Dr. Jose Santos (00:24:02):
So the next 35 to 45 weeks, whereas this year will affect only the next 15 to 25 weeks of lactation. Now disease have a lot more to do with what happens to the cow than just that initial insult. So let's look at this experiment here that was conducted with beef cattle. This is a be beautiful piece of data that I wish we had this in dairy cows. So what these investigators are investigators are Oklahoma State University did, is that they categorized animals in multiple blood vessels in the port of vein, in the hepatic vein, in the mesenteric vein in artery. And by doing this and infusing a marker, they can calculate blood flow across of the portal, drain viscera across the liver and across the, the total SPL tissue. But here's what they did. They had animals that were kept as control.
Dr. Jose Santos (00:25:02):
So they received saline in the trachea, or they challenged those animals with a bacteria made high MOA that induces an inflammatory response in the lungs. So they had animals that were fed and animals that were fested for this discussion here, I'm gonna focus comparing the control with the animals that they induce an inflammatory response in the respiratory tract. And I wanna make a parallel between this tear here and a cow that develops metritis because they have many of the hallmarks of an acute inflammatory disease. Okay? So they have an acute in acute phase protein response. The cow also does they have destruction of tissue. You can see the cow also does, but they affect different tissues. So it may not be a perfect comparison, but it's probably the best that we have today. So this is the flux of amino acids.
Dr. Jose Santos (00:25:58):
They calculate the flux of multiple nutrients. And I'm gonna show you the flux of amino acids from his PhD dissertation. Every time the bar falls below the zero line, it means that the tissue is utilizing more than it produces. So there is a negative netfl every time the bar is above. The zero line means that the tissue, in this case, the liver, that's the tissue that we're looking at here, it means that the liver secreted more of that nutrient than actually extract. So nutrients are coming in from the hepatic artery and from the, and they're leaving the liver through the, so you can see that for essential amino acids, both are below the zero line. So the liver is extracting more than it can produce because obviously the liver is unable to produce essential amino acids.
Dr. Jose Santos (00:26:57):
Okay? But the interesting thing is that it's more negative for the animals that underwent the bacterial challenge. Now, let's look at the non-essential amino acids, those that cells can synthesize. Now, we see a positive flux for the control animals that receive saline, but continue to see a negative flux for the animals that had that bacterial challenge or induced inflammatory response. So if we look at the total amino acid flux across the liver, we see a big difference. So the difference here is about 2.6 smalls per day in a steer that weighs about 400 kilograms. So if we do a quick calculation and we use the average molecular weight of the 20 synthesizing amino acids, this 2.6 moles per day equates to about 380 grams of amino acid that is in the bloodstream, okay? That's in the circulation. And if we use an efficiency of amino acid extraction by the ma gland of about 0.69% of metabolizer protein into net protein in milk, that equates to the protein equivalent of eight kilograms of milk or 18 pounds.
Dr. Jose Santos (00:28:07):
So you can see that there is a shift in partition of nutrients with an inflammatory response that's pretty substantial. If what happens in the steer equates to what happens in a cow with an acute inflammatory disease, for example, that's postpartum nitrites. So not only disease induces this sickness behavior that cows eat less, they don't feel like doing things, but alters also how the cow uses nutrients and places more nutrients now to fight the disease process and less becomes available for production and growth. Now, this has to have consequences to reproduction, and we know very well. So let me show you some data in which we inseminate cows that we had previously diagnosed without any disease event in the first 60 days of lactation or cows that had at least one disease event. And then we flush those cows on the five and a half to six after insemination, and we evaluate fertilization in embryo quality.
Dr. Jose Santos (00:29:09):
So we recover 420 embryo cytes. And we can see clearly here that fertilization was reduced. The proportion of live embryo was smaller and the proportion of high quality embryo was also smaller. If we remove the cysts from the calculation, we see exactly the same picture of val fertilized eggs, the proportion of live embryo and high quality embers in these cows that were not super ovulate. So this is what happens in a typical farm. So this was done in a commercial dairy farm, and you can see that we detect a red reduction in embryo quality, which means by day one or two after insemination, we have fewer pregnancies in those cows.
Dr. Jose Santos (00:30:00):
Now, this must be a problem with high producing cows, okay? So we decide to go and investigate this on a farm with this type of cattle. These are hosting zebu crosses that produce about 7,000 kilograms of milk in a grazing type of system. So a cow that produces 15 to 16,000 kilograms of milk, and we diagnose disease, Ingrid diagnosed disease in those cows, and we segregate cows without any uterine disease and cows that had at least one uterine disease. And here includes metritis, clinical endometritis and subclinical endometritis. So most of this uterine disease was composed by cows that had subclinical endometritis. In other words, we don't find clinical signs of disease in those cows, but they have an inflammatory response in the uterus. So what happened, the beauty of this study is that 100% of these cows only receive timed embryo transfer.
Dr. Jose Santos (00:31:05):
So they did not receive any ai, it's only timed embryo transfer. So we bypass fertilization in the very early stages of embryonic development, and these cows receive an embryo. So we looked what was the service rate, or let's say quote unquote insemination rate, if you will. You can see that it is smaller for cows that had uterine disease to a large extent because those cows had a smaller pregnancy per embryo transfer. By reducing pregnancy, you'll also affect in service rate. And by doing this, we affect pregnancy rate. You can see that the 21 day cycle pregnancy rate was smaller for cows that were diagnosed with urine disease in the first 32 days postpartum. Okay? And this result in an additional 32 days or median days to pregnancy in cows who develop uterine disease compared to cows that did not have uterine disease. And remember, most of these uterine disease here, it's not necessarily a clinical disease that we see by just collecting uterine or vaginal discharge.
Dr. Jose Santos (00:32:22):
So what's going on here, we think that this inflammatory response can alert the maternal immune in addition to causing damage to the tissue affecting fertilization affecting the ovary, affecting the quality of the oversight and multiple aspects. But this also affects the ability of the uterus to sustain pregnancy. And for that to happen, the maternal immune system in the reproductive tract has to tolerate components of the embryo that have foreign proteins such as the proteins that are induced by the fact that half of the genetic material of this embryo comes from the paternal side, what we call this paternal allo antigens. And we think that when we have an inflammatory response, in particularly in the reproductive tract, this can affect the ability of the maternal immune system to tolerate those embryonic proteins. And that can induce increased pregnancy loss among other factors.
Dr. Jose Santos (00:33:28):
So, second, take home message. We need to stimulate intake that influences nutrient balance that affects resumption of cyclicity cyclic cows have increased Astros expression, pregnancy pre insemination, and they're more likely to maintain their pregnancy. We also need to minimize disease because disease cause inflammation and tissue damage, and that alters how nutrients are used. And now it favors control of the infection and inflammatory response at the expense of growth and survival growth and, and reproduction, I'm sorry. So the priority now shifts to survival. And this has long-term effects on reproduction. Now, let's just shift gears, and I'll give you a couple examples. If the goal is to reduce problems, we need to think about how we formulate diets that will improve reproduction, and we should focus on these two important concepts. We know that reproduction is reduced once we have disease.
Dr. Jose Santos (00:34:36):
So it's obvious that we should formulate diets that reduce the risk of disease. That's the first aspect. And then we should incorporate nutrients that are known to show a benefit to reproduction in cows. So I'm gonna give you a few examples just because we don't have time to cover, you know, a a, a very extensive area. So lemme show you one nutrient that can influence the risk of disease or metabolic disorder. One of which is choline. Choline is this molecule that you saw in the video early on that once consumed can be utilized to synthesize this larger molecule here. Actually, there are many molecules that is called phosphocholine that can be quite variable in its composition of fatty acids that's connected here to this glycerol molecule. And phosphocholine is very important because it plays numerous roles and it's part of, almost, it's part of every cell in the body.
Dr. Jose Santos (00:35:40):
Okay? One of those roles of phosphocholine is to be part of this large molecule that's called very low density lipoprotein. Okay? And phosphocholine which are the phospholipids in the surface of this large molecule, allows this lipoprotein to contain lipids in its score or fats in its score, and contain proteins in the outside that allows it to be missable in a output solution. So in this experiment here by Dr. Marco Xenobi, we induced cows to develop fatty liver, and then we fed increasing amounts of choline ion in a room protected form. Okay? This is the concentration of triglyceride in the liver. When cows were in the well fed state, they were receiving the diet at Liptum, and then we fed restrict those cows for nine days. And what happened was that hepatic triglycerides accumulate in the hepatic tissue, but the accumulation was less and less and less as the amount of choline ion consumed by those cows increase.
Dr. Jose Santos (00:36:52):
So it shows here this linear decrease in triglyceride accumulation as cows were supplemented with choline ion. So choline like in for dairy cows, like in any other species, has this lipotropic effect, and we think is linked to the ability to synthesize and secrete lipoproteins to export lipids from the liver. Obviously, these cows have a smaller risk of developing fatty liver, and if that's true, this should benefit lactation performance. So here is a meta-analysis that Usman had conducted to look at all the literature we could find with controlled experiments in which cows had a controlled diet without supplemental choline ion as a room protected choline product, or they were fed some amount of choline ion in a room protected form. So the names here on the left are the reference, okay? From the experiments in which choline was fed during the transition period to be part of this meta-analysis the treatment had to start prepartum and continue until at least the day of giving, but most of them fed cows until several weeks postpartum.
Dr. Jose Santos (00:38:06):
So, so the way you look at this here, each row here represents a comparison between a certain amount of choline ion in a room protect choline form compared with the control within that experiment. And you can see all the comparisons that are available here. The black dot represents the point estimate. The gray circle represents the weight of that comparison in the statistical analysis, and the horizontal line represents the 95% confidence interval. So here it gives you a very good idea how repeatable the results are. And in general, most point estimates fall to the right side of the central line. And the central line is basically where there is no difference between the treated and the control. And this here is expressed as what we call standardized mean difference. So number of standard deviations, and the response evaluated here is energy corrected milk. So you can see that most responses fall to the right, okay?
Dr. Jose Santos (00:39:11):
And in fact, the overall response from this analysis show an increase in energy correct milk of point 38 standard deviations, which represents an increase of about 2.2 kilograms of energy, correct milk production per day in the first few months of lactation. So this shows that benefiting health has a positive impact on production. Now, lemme give you another example of a manipulation, the diet that provides benefits to health and production. So these are a, a list of mechanisms involved on how a cytogenic diets prevent hypocalcemia in calciums. Just quickly, when we induce a, a slight metabolic acidosis, we ionize calcium that's present con associated with proteins or in the form of salts. So now we have more ionized calcium in blood. Acidosis stimulates the thyroid gland to secrete more thyroid hormone, which is one of the tropic hormones that control blood calcium acidosis, increases tissue responsiveness to thyroid hormone.
Dr. Jose Santos (00:40:22):
And once PTAH is more active, that induces more synthesis of active vitamin D three in the kidney cells. So this hydroxylation of 25 hydros D three into 1 25 dihydroxy D three is stimulated. A very important mechanism of this cytogenic diets is to increase calcium excretion in the urine because acidosis blocks a a calcium channel here that is responsible for reabsorption of calcium that's present in the filtrate. So when the blood, when the urine IPH is acidic, this calcium here, this calcium channel, I'm sorry, shuts down. So calcium is not reabsorbed. And now the cow secretes calcium in the urine in this increased secretion of calcium urine, upregulates, all the systems that contrary like calcium before Calvin, one of which is increased calcium absorption in the gastrointestinal tract, which is illustrated here. And finally, this slight metabolic acidosis induces cells in the bone, these macrophages here to scavenge the mineral matter of bone that releases calcium to the bloodstream.
Dr. Jose Santos (00:41:37):
So this combined effects improve blood calcium concentrations and prevent cows from having clinical as well as subclinical hypocalcemia. So this should benefit animal health. And we know very well that risk of milk fever is greatly reduced by feeding cellgenic diets. But not only that, as you can see that the risk of retained placenta and the risk of metritis two important disease that affect the reproductive tract, they are both, both reduced as the dietary cat and ion difference of the diet. Prepartum moves from positive to negative. So when we feed the cytogenic diets the risk of uterine disease decrease in dairy cows, and we know that uterine disease affect production and affect reproduction. And if we have less uterine disease, we should have improved production. And in fact, if we look at milk killed and fat, correct milk killed, when we feed the cytogenic diets, both of them increase in per cows.
Dr. Jose Santos (00:42:44):
Now here's an important point, and remember that I told you that in the transition period we hope to be able to group cows and heifers separately. One of the reasons is that heifers do not respond with an increased meal killed by feeding the cytogenic diet. So we don't get that benefit from Noro cows, but we do get a important benefit of feeding cytogenic diets to per cows because we prevent milk fever, we've reduced the risk of uterine disease, and we produce more milk or fat, correct milk postpartum. Now, an important aspect and goes back to this grouping of cows, is that those diets should be fed only during the closeup period. Okay? So here's an experiment in which we fed exactly the same diet, but we manipulate the decab and we've offered cows the diets the a cytogenic diets either for 21 days the last 21 days of gestation, or the entire dry period, the last 42 days of gestation. And this is the rate of pregnancy in those cows. And you can see that the rate of pregnancy was faster for cows that received the diets for 21 compared to 42 days. And you can see that the cows that received the cytogenic diets for three weeks only produce more fat, correct milk and more energy correct milk, than the cows that were fed for 42 days. So we think that cows should not be fed as cytogenic diets during the entire dry period.
Dr. Jose Santos (00:44:16):
Forage quality is very important, and I think that's been neglected during this transition period. And this is a typical diet of a cow. It's composed of forage, a starch source, byproducts, protein supplement mineral vitamins, and a source. In this example here, I have a forage that is of moderate to low quality. So I have limited inclusion in the diet. Each square here represents a kilogram of diet. I have a total of 24 kilograms, or each rectangle, I'm sorry, represents a kilogram. Each square is half a kilogram. So I have 24 kilos of which 10 kilos are represented by forage. If I feed more, these cows are not able to produce the 41 kilograms of milk with three seven fat, three, two protein. But if I have better quality forage, I can occupy more space on my diet with forage, which it's typically cheaper and is typically healthier and safer for the cow.
Dr. Jose Santos (00:45:18):
Okay? And that's what I'm doing here. Well, obviously this is just a simulation, so let's see if this is real. So here's a beautiful experiment out of Cornell University by Bill Stone, in which they manipulate the type of corn silage that was fed during the transition period from three weeks before to three weeks after calving only six weeks of intervention. And they follow those cows for 15 weeks after ca. So what were the treatments? It was a conventional corn silage or a brow meat rib corn silage. So this has lessening, and the neutro detergent fiber is more digestible. So each kilogram of silage provides more nutrients for the cow. So what happened in the first three weeks of lactation cows were fed. The BMR corn ate two kilograms more. What happened after three weeks postpartum? Once they all received the conventional corn sage. So no more, no more treatment being applied here.
Dr. Jose Santos (00:46:18):
They ate the same. Okay, but now look at the fat correct milk. It was always greater for the cows that receive the more digestible fiber source coming from corn silage. They produce here four kilograms more milk in the first three weeks, and they continue to produce 2.7 kilograms more fat, correct milk after these cows receive exactly the same diet. Okay? So that's another example of a dietary change that benefits transition cows. Now my last point is something that can benefit reproduction directly. So this is an experiment from Jonas de Soza in the group of Adam Locke, Michigan State in which they supplement cows a diet without they fed cows, a diet without supplemental fat control, or they add 1.5% additional fatty acids with different combinations of fatty acids. So I don't wanna touch on different combination of fatty acids, I only want to look at the effect of fat feeding, which is the average of these three groups versus control.
Dr. Jose Santos (00:47:25):
And you can see that there was no difference in dry matter intake in the first three weeks of lactation. So supplying 1.5% of the diet dry matter as fat supplemental fatty acids did not depress intake in early lactation, but it did stimulate energy, correct? Milk dose cuts. They produce five kilograms more energy corrected milk in our lactation. So you can stimulate production. Now, what happens to reproduction? So here's a meta-analysis from the Australian group Dr. Ian Lean and his students in which they pulled data from the literature and they look at 17 experiments with individually fed cows that included 26 comparisons between control or some amount of supplemental fatty acids added to the diet. Starting in the transition period, they had almost 1400 cows. There were multiple fat sources used. But here's the overall message. From that meta-analysis, there was a 27% increase in risk of pregnancy, meaning that the controls would average 32, the treated would average 40%.
Dr. Jose Santos (00:48:32):
So a substantial increase in this result in a tendency for fewer days open, the cows tended to produce more milk. The milk composition didn't change, and this cows did not change. There was no change in body weight. No difference in body weight changes between the control and the treated animals. So improvements in reproduction without negative effects on body tissue and with additional milk production. So diets of early lactation cows should contain some amount of supplemental fat, and we should limit the total fatty acid content to somewhere between four and 5% of the diet dry. So just to finalize, here's some important points. Feed prepartum diets to supply sufficient energy. And you can look at what this value should be. The new nascent 2021 provides good information on that supplement room. Protect choline. If the goal is to reduce the risk of hepatic lipidosis and improve milk production in early lactation, formulate diets with a negative dec to prevent hypocalcemia in the neck.
Dr. Jose Santos (00:49:42):
Negative consequences of low blood calcium such as uterine disease, metritis retained placenta. Move these cows to the closeup when they are about three weeks before they expect having date. So move them when they are between 250 to 255 days of gestation. Segregate new lippers from per cows. One reason is protein needs. The other one is the response to a cytogenic diets and the other one's just cow behavior. I don't, I I'm not gonna touch on this here. Postpartum feed, high quality forges. This is usually better, healthier, and often cheaper. We didn't talk about this, but protein in the early lactation diet's quite important. Be careful to not short to not have limited protein diets in the first few weeks of lactation because this can compromise productive performance and supplement moderate amounts of fatty acids to improve fertility. Anywhere between one to one half percent of the dry matter as supplemental fatty acids should be added to the diet.
Balchem (00:50:44):
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Scott Sorrell (00:51:11):
Josee. Your first question is related to the dry cow period. It says that it seems that the single dry cow group management has become more popular recently. Many dairies do this to improve labor efficiency. What does a cow miss out on when managed in a single dry cow group? I think that's also also relevant right to our some of our European producers as well, that, that have only one cow dry group. Go ahead Todd.
Dr. Jose Santos (00:51:40):
Yeah, so obviously when you do this, it's because you had either constraints in terms of facilities or you have this aspect of optimizing labor. It doesn't mean that it's better for the cow. So that's, that should be clear. Okay. So the, what we are missing is that obviously we're spending a little bit more money over the entire dry period doing things that probably the early dry cows don't need such as some feed additives that are probably not needed in the diet. If we're feeding a cytogenic diets there is probably a negative consequence of feeding for the entire dry period. 'cause Acidosis has its role, it's beneficial for mineral metabolism, but it doesn't need to be fed for 45 to 60 days. And lastly obviously we would be spending money, for example, with additional protein in the diet, or if we are adding a little bit more energy in the closeup group, if we do this now for seven to eight weeks, there's a chance of cows accumulating a little bit more visceral fat, which is not advantageous to them. So if we have cows eating well 12 to 13 to 14 kilograms of dry matter a day becomes an issue formulating a single diet that prevents weight or body fat gain in the early dry period, and at the same time stimulates intake once they get closer to calving. So, so those would be the, the major issues in my view.
Scott Sorrell (00:53:09):
Alright, thank you Jose. Go. Swami is asking what is the significance of lower pH values below 5.50,
Dr. Jose Santos (00:53:18):
That's actually not a good thing. So when you, once you get cows to very low pH, which a lot because it becomes more consistent, but for the cow that's detrimental. So if cows develop what we call uncompensated metabolic acidosis, they are unable to maintain blood pH the first blood pH. So the first thing they do is they back off on intake. That's the first thing they will do. Acidosis suppresses appetite, but there are other consequences, one of which is that it inhibits insulin released by the pancreas and inhibit insulin action on peripheral tissues such as the a post tissue. So when we induce severe acidosis in cows, let's say if your cows are having urinary pH of five and a half, 5.2 not only they eat less, but now they also start to mobilize more a post tissue. So this can set them up for other type of metabolic disease such as fatty liver ketosis. And the reduction in dry matter intake may set them up for displacement of abo that's not recommended. So if you're using a cytogenic diets target an average of 6 2, 6 3 and aim such that almost every cow is between five, eight and seven. So you have a variation among cows, but make sure that every cow is between five, eight and seven with a mean for the group of about 6 2 6 4.
Scott Sorrell (00:54:47):
Alright, Jair is asking do you see a potential for feeding specific fatty acids during the prepartum period?
Dr. Jose Santos (00:54:56):
That's a, that's an interesting question. I think there is, but we lack data to be honest. So we know that fatty acids have this nutritional role, but they're also very active molecules and it's probably possible to manipulate this inflammatory response that normally happens in early lactation by altering the types of fatty acid we provide in the diet. So if you ask my feeling, but it's, i it's not backed up by really strong data. It's that if we were to feed fatty acids of the Omega-3 family, such as alpha linoleic acid a coop anti AIC or doose AIC acid, and we were to enrich the phospholipid layers in tissues with those fatty acids, probably we could reduce a, an exacerbate inflammatory response in early lactation, which would probably bene be beneficial to tissues such as the reproductive tract or a general inflammatory response that would probably consume more nutrients than needed. So I think there is an an opportunity there, but I don't think we know very well about it because we don't have enough experiments or data who have that have tested that hypothesis.
Scott Sorrell (00:56:14):
Alright, makes sense. Mohammad would like to know your recommendation for using mono prop propylene glycol in the transition period.
Dr. Jose Santos (00:56:23):
Well, my recommendation is to not use unless the cow needs
Scott Sorrell (00:57:25):
All right. Dr. Chad Jenkins is asking, do you think there is a value to cos supplementing choline and methionine during the transition period? Or does it make more sense economically to choose one or the other?
Dr. Jose Santos (00:57:37):
I think there is a role for both of them. My opinion, I think the importance of methionine in lactating diets is unquestionable. So, and I think the role of choline in the transition period is also unquestionable at this point. So if I could choose or if I would feed choline room protect choline during the transition period, so starting at 250, 255 days of gestation and continue until the cow leaves the fresh pen, and I would definitely formulate for amino acids, which means include methionine in early lactation. There's probably a role for methionine prepartum as well, but I don't think we have those data just with methionine prepartum. So almost all experiments that have methionine transition period fed before and after. So we need some experiment that explore just feeding prepartum to understand whether that additional meine, those extra four or five grams of metabolized meine plays a role in postpartum health and reproduction of cows. I think when you feed during the entire transition period before and after having, there's lots of very good data from multiple places that show benefits to that. What we don't know is just feeding prepartum is needed because I can easily increase the overall metabolizer protein in the diet by just feeding a little more soybean meal or, or some, some other protein source.
Scott Sorrell (00:59:09):
Very well. Just a, we just passed the top of the hour. We have a lot more questions. Can you stay on for just a bit?
Dr. Jose Santos (00:59:16):
I'll be glad to. Alright,
Scott Sorrell (00:59:17):
Very well. Dr. Aldridge is asking, what is a mechanism whereby feeding low dec ad for 42 days versus 21 days had a negative effect on pregnancy rates?
Dr. Jose Santos (00:59:30):
Yeah, we don't know. I'm gonna be a hundred percent honest, obviously. There are that I'm aware three experiments in which cows were fed cytogenic diets either for six to eight weeks versus only three weeks in our three experiments energy, correct milk or fat. Correct. Milk will reduce at least numerically, not statistically, but they always, the point estimate always went to the same direction. Okay? So when we pull those data from the three experiments then I can show a, a statistical effect if I do a quick meta-analysis on that analyzing those data. So your question is why would the reproduction be affected? So I can come up with some hypothesis. The first one is that acidosis, the only reason why at this point that we know of that we want to induce metabolic acidosis to increase this flux of calcium through the body that prevents hypocalcemia.
Dr. Jose Santos (01:00:30):
We don't have any good data to show that inducing metabolic acidosis per se, without altering calcium or mineral metabolism is beneficial to the cow. In fact, if I do this in during lactation, it's detrimental to cow performance. Cows eat a little less when they are fed during the entire dry period. So that may have some negative implications later on to health and reproduction of those animals. But we don't really know because we don't have extensive data on that. It's a single experiment with 114 cows and that's what we observe. So there is some indication that's not beneficial. But we don't understand. The mechanism I think is related to the fact that metabolic acidosis was designed to prevent hypocalcemia, but it was not designed to have this overall health benefit to cows. And when we induce metabolic acid dose for too long, or if we have condensate metabolic acid dose, we can have those potential side effects such as increased lipo mobilization, reduce dry matter intake that may have consequences to reproduction without understanding necessarily the exact cellular mechanism.
Scott Sorrell (01:01:48):
Alright, thank you Jose. Ahmed is asking what could be the in logical interventions that we can do in transition period to stimulate dry matter intake?
Dr. Jose Santos (01:02:03):
Oh, that is the million dollar question. Yeah. Knowing what induced cows to eat more, I can come up with things that suppress intake. So you should probably avoid those
Dr. Jose Santos (01:03:16):
And that happens in cows, in flies, in whales, in any species that's being studied. So I think what we know is what to avoid, what we don't know is exactly what triggers the cow to eat more. Okay? So we need to do things that remove those obstacles and hope that this cow now can consume an extra one or two kilograms of dry matter that's pretty critical, particularly in early lactation to avoid displaced double macin and other disease. Sorry that I don't have a a, an exact answer because I think we lacked knowledge on that particular area. We know very well what's bad, but we don't know necessarily what triggers appetite.
Scott Sorrell (01:03:57):
Alright. Christiano is asking, I'm feeding onic diets with particular dec ad in heifers as well because it improves the uterine health after calving. What do you think about that?
Dr. Jose Santos (01:04:10):
Yeah, so so we've done two experiments with just heifers here after that meta-analysis that we published a few years ago. So we had two experiments with about 230 heifers individually fed. And again, we re replicated no benefit to milk production between an genic and a cytogenic diet in one of the experiments, a moderate cytogenic diet. And what I mean by that, the DEC was minus 50 milli equivalents per kilogram. For those that use a hundred grams is minus five milli equivalents per a hundred grams. Those animals had a little bit better health morbidity was less in those heifers. In the second experiment, we fed minus 50 milliequivalents per kilogram versus if I recall, plus 200. We had about almost a hundred heifers, 50 per treatment, and we did not detect a benefit to health in those animals.
Dr. Jose Santos (01:05:13):
So in the meta-analysis, if I go back and I showed you the data, you have to remember that 85 to 90% of the data came from experiments with per scales cows starting their second or greater lactation. And mathematically you don't necessarily separate the effect of the pers and newly per scales because you may not have enough power to detect an interaction for disease. Not every experiment reported disease incidents. So when we go from all the experiments that reported some of the aspects that we were interested on to uterine disease, we lose a lot of data because people just don't report when they publish some experiment, don't report some data when they publish experiments. So when we get down to the disease data, we may not have enough power to detect an interaction between DEC and parity. So then if the interaction is not there, the point estimates gonna go in the same direction whether we have a he or a cow. And I am, I'm not convinced at this point that we get the same benefits in health for the heifers. I think if we do, it has to be a moderate dec. You cannot go to the same level of acidosis as we typically use for cows. So we shouldn't be feeding a heifer a diet or minus 100 or minus one 20 milli equivalents. That I, I feel very comfortable saying,
Scott Sorrell (01:06:39):
Well, this is a different question. I think it's a real one. I'm gonna ask it. What, what about the use of endocannabinoids to increase feed intake
Dr. Jose Santos (01:06:47):
Yeah, I probably, I will defer because I don't know enough data on that. And I think it's probably an area people are studying. There is a group in Israel and a group of Michigan, Stu State University studying endocannabinoids and their role in ad post tissue metabolism, appetite regulation. But I'm not sure if we understand exactly how it works very well in the cow. I mean, and how to implement that at this point. But I'll be glad to point out to people who probably will know better than I do in that, that area.
Scott Sorrell (01:07:29):
Alright, thank you. Adrian is asking, regarding the data on disease and reproductive performance, what would be your comments on the 35% of no disease cows that did not get pregnant? What do you think are the main risk factors for four poor fertility in non disease cows?
Dr. Jose Santos (01:07:49):
There are many reasons. Yeah. So you gotta remember that disease is one component that can negatively influence reproduction, but I can come up with many reasons. So hormonal, not proper reproductive, proper ovarian response to hormonal treatments. So let's say you have a perfectly healthy cow, but she doesn't completely regress the corpse lute. When you synchronize her for insemination, a little bit of progesterone can either block ovulation or block sperm transport. Your technician doesn't deposit semen properly. The se quality is less than ideal. This cow is healthy, but she has hyperthermia. So there can be multiple reasons other than disease that can impair reproduction. And this is why you always have to think about populations. Yeah. And you have to look at groups of cows and not just individually, particularly on, on herds. And unfortunately, there are many reasons disease being one of them that can affect reproductive performance.
Scott Sorrell (01:08:53):
All right. Jair is asking, what are the best, what are the best hypothesis behind more efficient cows? What anatomical or metabolic effects could be implied?
Dr. Jose Santos (01:09:03):
Yeah, this is very puzzling, I have to say. And we have data in beef cattle. We have a little bit of data in dairy cattle. So they, I think they're obviously different. There are genetic differences and they're obviously major phenotypic differences. So I can come up with a few possible ideas. Yeah. So those cows might spend less. They have may have less maintenance requirements requirement requirement. So we applied this rule of 100 kilo calories of net energy for every kilogram of metabolic weight as a rule for every cow. Yeah. So if a cow weighs 600 kilos, and if I have a hundred cows, the six weighs 600 kilos, they all have the same maintenance requirement, and we know that that's probably not true. So they may have differences in maintenance requirement, that's one of them. They may have differences in body composition that out alters maintenance requirement.
Dr. Jose Santos (01:10:00):
They may have differences in digestibility. So just how they digest feed, maybe the more efficient cow choose to choose more, more her ru microbiota is more efficient. Maybe the way the microbiota uses the carbon in the rumen is different. So favors one set of short chain fatty acids versus another, maybe they absorb better nutrients maybe during the post absorptive metabolism. They have less futile cycles, so they utilize nutrients more efficiently. For example let me give an example of amino acid utilization by the memory gland. We know that different amino acids are extracted by the memory aphelion with different efficiencies. We use a value. And I think the new nascent dairy cattle uses a 69% efficiency of amino acid extraction from blood into milk protein. So perhaps the more efficient cattle has an efficiency of 75 or 80% amino acid deficiency, maybe they degrade less protein in the room, and so they preserve more amino acids. So proteol and the ammunition is outer, which favors amino acid absorption. So there are multiple reasons,
Scott Sorrell (01:11:31):
On behalf of Balchem and Dr. Santos, thank you for joining us today.
Dr. Jose Santos (01:11:36):
Hello everybody. My name is Jose Santos. I'm a professor in Department of Animal Sciences, and I want to take this opportunity to invite everybody to come to Gainesville next month to attend the Florida Ruminant Nutrition Symposium on February 24th to 26 2025. So we've prepared the an excellent program with the help of Balsam Purdue Agribusiness and other sponsors that will be probably very enlightened in terms of content networking and other opportunities. In this particular slide here, you have two links that can take you to our registration website either to the symposium website or to the registration itself. As part of our program for the 2025 event, we have a mini symposium, traditionally that's been sponsored by ballam. So we are bringing Dr. Tara Felix from Penn State University, Dr.
Dr. Jose Santos (01:12:51):
Brett Johnson from Texas Tech Dr. Albert Reese here from the University of Florida, and Dr. Tom Overton from Cornell University. And they are gonna dive in and spend the entire afternoon discussing multiple aspects of beef on dairy carcass composition management aspects relative to the performance of those animals and feedlot the economics of beef found dairy, as well as transition cow management, in particular, the dairy cow, the transition dairy cow. So following the Balam Mini Symposium, we have a traditional Brazilian, what we call s hasco or, or asado for those friends from the south, or a barbecue that you're gonna be delighted to attend. And the following day, on Tuesday, we have a packet day with the morning being sponsored by Purdue Agribusiness with a major focus on room metabolism and animal health.
Dr. Jose Santos (01:14:05):
We have Dr. Jeff Kins from the Ohio State University discussing aspects of room fermentation. Dr. Dakkar V here from the University of Florida, Dr. Alex b from Spain, and Dr. Lynch Bogar from Iowa State university. So the whole morning will be taken by those four speakers with a lot of discussion followed by lunch. And then we have a full afternoon plan for that Tuesday, February 25th. So in the program of Tuesday afternoon, we have this lineup of speakers here on top. And for the Wednesday morning, we have this other lineup of speakers here on the bottom. So, Dr. Bob Cousins, who is an expert on zinc metabolism and zinc transport will start our afternoon program followed by Dr. Dave Frasier from university of Sydney, college of Veterinary Medicine in Australia. And we're gonna finish our first session of the afternoon with Dr.
Dr. Jose Santos (01:15:14):
Jerry Spear. So the whole goal of this first session in the afternoon is to really target and focus on mineral metabolism. Dr. Cousins will discuss zinc. Dr. Fraser will focus on calcium. And then Dr. Spears will talk about different sources of trace minerals for ruminants. So we'll have a break followed by three other speakers who will focus primarily on manipulations of the early calf and impacts on lifetimes. So Jim, directly, Dr. Jim directly from University of Illinois, will talk about nutrient requirements of the Prew dairy heifer, followed by Dr. Javier Martin Tereso from trial nutrition in the Netherlands. He is gonna discuss experiments in which they manipulate the diet during the Prew period and what impact that has on lifetime productivity. And then we have our own PhD student here, Masure Sge, who works under the mentorship of Dr.
Dr. Jose Santos (01:16:25):
Pete Hansen, who's been doing experiments, looking at manipulation of the medium in which embers develop early on and what impact that has on the offspring. He's also conduct experiments in which he's strategically supplemented methyl donors, such as room protected choline looking at potential impacts on offspring development in beef and dairy cattle. In the following day, we have a mixture of presentations, fo presentations, focusing on newer methods to understand room and fermentation using breadth of cows, which is what Dr. Muan knew from Switzerland is gonna discuss with us. So they have new technologies that can be used that are not invasive to evaluate Ruminal fermentation. Then Dr. John Kisser will talk about new methods to evaluate forestage quality and how that can play a role in diet formulation for dairy cattle. Our own La Lima who is a PhD student under the mentorship of Dr.
Dr. Jose Santos (01:17:41):
Divakar vs. Will talk about the experiment she's done looking at nutrient cycle on a farm focusing primarily on nitrogen, but other nutrients. And then we have, again, Dr. Brad Johnson, Dr. Tara Felix, which will complete the program on that Wednesday, discussing impacts of beef on dairy on the cow itself, the cow that carries that calf. That will be some of what Dr. Tara Felix will discuss. So now going back of Bifo Dairy Implications to the Dairy Cow and Dr. Brad Johnson will discuss aspects of tissue deposition, add and muscle deposition in animals relative to interventions with beef on dairy. So we believe we have a attractive program with a lot of interesting information. Don't be shy to go to our website and check our program and opportunities to come and attend the conference. So I hope that you'll come to Gainesville, particularly if you're from the northern states of the US or Canada or other places. Come here to get a few days of collegiality defrost. Some will be warm, hopefully here in Gainesville and enjoy this extension program. So I thank you and I hope to see you all here in Gainesville next February.
Balchem (01:19:14):
We'd love to hear your comments or ideas for topics and guests. So please reach out via email@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 anhmarketing@balchem.com. Balchem’s real science lecture series of webinars takes place on the first Tuesday of every month with the top research and nutrition topics that will impact your business. We also include small ruminant, monogastric, and companion animal focused topics throughout the year. Visit balchem.com/realscience to see the upcoming topics and to register for future webinars. You can also access past webinars and search for the topics most important to you.