Guest: Dr. Sandra Godden, University of Minnesota College of Veterinary Medicine This episode is from a webinar presented by Dr. Sandra Godden from the University of Minnesota Department of Veterinary Population Medicine. To view the full webinar and access the slides referenced during this podcast, visit balchem.com/real science and scroll down to the webinar presented on November 8, 2023.
This episode is from a webinar presented by Dr. Sandra Godden from the University of Minnesota Department of Veterinary Population Medicine. To view the full webinar and access the slides referenced during this podcast, visit balchem.com/real science and scroll down to the webinar presented on November 8, 2023.
Dr. Godden begins with the reminder that despite decades of research and definite advances in colostrum management, there's still a lot to learn and research. Her goal is to give an update on new findings that can be utilized in your colostrum management program. (0:21)
Promoting calf health and growth is a balance between maximizing immunity and minimizing infectious disease challenges. Colostrum is one aspect of maximizing immunity and provides passive immunity in the form of immunoglobulins. It also contains bioactive compounds, immune factors, growth hormones, leukocytes, and nutrients. (1:09)
We can measure adequate transfer of passive immunity via serum immunoglobulin G levels, where anything greater than 10 grams per liter is a pass. Passive transfer of immunity is associated with reduced morbidity and mortality, especially in the first 2-3 months of life. Successful passive transfer has many other intermediate and long-term benefits, including improved growth rate and feed efficiency, leading to even longer-term benefits of decreased age at first calving and potentially improved milk production in the first and second lactation. (4:18)
When building a comprehensive colostrum management program, Dr. Godden distills it down to the five Qs: quality, quantity, quickness, squeaky clean, and quantifying. Starting with quantifying passive transfer, in a perfect world, we would have a quick, inexpensive, on-farm serum IgG test that could be run on whole blood. Unfortunately, that test does not exist. In research studies, we send serum samples off to reference labs to have serum IgG tested. On-farm, we use indirect tests such as serum Brix or serum total protein. Historically, the literature has said that a serum total protein of somewhere between 5.0 and 5.2 grams per deciliter most accurately predicts that IgG value of 10 grams per liter. If greater than 10 g/L IgG is a pass, is a higher concentration better? Yes. A good goal would be for 90% of the calves to have serum IgG higher than 10 g/L. More specifically, goals are around 40% of calves in the excellent zone of 25 or greater, roughly 30% of calves in the good zone of 18-25, and around 20% in the fair zone of 10-18. Dr. Godden references the corresponding Brix and total serum protein readings in her slides. (7:24)
Quality refers to the concentration of IgG in the colostrum, and experts have suggested that be at least 50 grams per liter or higher. This corresponds to a Brix reading of approximately 22% or higher. Several factors influencing colostrum quality are under our control, including the dry cow vaccination program, feeding a balanced dry cow ration, avoiding stressors during the dry period, avoiding excessively short dry periods, and milking cows out as soon as you can after calving. (16:18)
When it comes to quantity, a larger volume at first feeding will result in higher IgG concentrations in the calves. One study compared feeding two or four liters at first feeding with a second feeding of two liters at 12 hours. The higher volume first feeding showed better results. (29:23)
As for quickness, IgG absorption efficiency is optimal in the first couple of hours after birth but is then slowly reduced as gut closure occurs. Ideally, we want to feed the calf as soon as possible, hopefully within one to two hours of birth when possible. (30:35)
The last Q is squeaky clean or cleanliness, specifically the level of bacterial contamination in colostrum. Obviously, we don't want to feed colostrum that is laden with pathogens that can cause disease. However, high bacteria counts in colostrum have also been associated with reduced absorption of IgG. Dr. Godden details a number of critical control points that can be assessed if colostrum cleanliness is an issue of concern. (38:19)
Dr. Godden finishes the episode by taking questions from the webinar audience, ranging from average colostrum volume collected at first milking to what temperature colostrum should be frozen at to heat stress impacting quality and quantity of colostrum. (49:20)
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Kim (00:00:00):
The following podcast is taken from a webinar presented by Dr. Sandra Godden from the University of Minnesota, department of Veterinary Population Medicine. To view the full webinar and access the slides referenced during this podcast, visit balchem.com/realscience and scroll down to the webinar presented on November 8th, 2023.
Sandra (00:00:21):
Thank you, Kim, for the opportunity to be here today. We're gonna talk about a topic that is still near and dear to my heart. And despite decades of research and, and definitely advances in colostrum management, there's still a lot to learn and still a lot of active research. So today we'll kind of give an update and, and hope to talk about some new or some recently new findings, things that you can help, help out with your colostrum management program on your farm. But if questions come up and we don't know the answer to you, my experience has always been that the best research questions come from the field. So if we can answer your questions at the end of today's session, great. If we don't get to all the questions, as Kim mentioned, you can drop me an email at any time and I'll be happy to respond.
Sandra (00:01:09):
And as I just alluded to, if questions come up that we don't have answers to, you know, maybe those are some great ideas for upcoming new research projects. So let's get started though. So just backing up a little bit, we're talking about our replacement heifer programs and there's a lot that goes into managing heifers, obviously, but general areas to promote health and growth. One is going to be maximizing immunity, which of course includes colostrum. The Milk New Milk program, milk nutrition program is, is really, really critical as well, minimizing stressors. And then vaccination can play a role in your calf management program, but I would prefer to put emphasis on management first and vaccination as a secondary tool, and then minimizing infectious disease challenge. And that's going to include our choice of housing systems and how we manage that bedding, ventilation, and sanitation.
Sandra (00:02:07):
And between a combination of all of these different pros and cons, if you will, maximizing immunity, minimizing challenge, we hopefully will have a healthy calf growing well and well on our way to becoming a productive adult in your herd. Today, we're going to focus just on colostrum. So why is colostrum so important? If I ask my students that question, they know the answer is the antibodies, right? Those immunoglobulins that the calf doesn't get in utero in the uterus, but does passively absorb maternal antibodies through that first colostrum feeding and a little bit from second feeding and so forth. And we know the calf needs these passively absorbed antibodies to mount protective immune responses during the first days, weeks, and even months of life while it's building its own acquired immune system producing its own antibodies. So, yes, the antibodies in colostrum are important and we tend to focus on that when we're doing research looking at adequate colostrum management.
Sandra (00:03:10):
However, colostrum is not just about the antibodies. There are many, many multitudes of other bioactive compounds, immune factors, growth hormones, leukocytes, and especially nutrients in colostrum that are gonna benefit this calf's health and growth. Nutrients in particular are interesting in Holstein tank milk, we expect total solids to be roughly 12.5%, let's say in colostrum, that's gonna be closer to 24%. So we're seeing very high levels of fat or calories coming in higher, higher levels of protein, and not just globulin protein, but dietary protein, higher levels of many of our vitamins and minerals. So colostrum, it's about the whole package. Yes, we will frequently default back to measuring passive absorption of serum immunoglobulin, especially immunoglobulin g as our marker or way of monitoring passive transfer. But we have to remember, there's all these other things that are contributing to calf health and growth and future performance.
Sandra (00:04:18):
And why should we care about doing a good job with colostrum? I'm sure you're all familiar with the fact that calves get adequate transfer of passive immunity, and we can measure serum immunoglobulin G levels to measure this. Very simply, anything greater than a 10 gram per liter in the serum of the calf is a pass. We'll talk about goals a little bit later. So we know this is associated with reduced morbidity or disease and reduced mortality or death, especially in the early months, you know, first two, three months of life. But it doesn't just stop there. There are many other intermediate and long-term benefits of successful passive transfer. In addition to improved health, we see improved growth rate and feed efficiency, which means that if you are looking to breed animals, getting to them to breeding stature or size sooner, this is going to help, it'll help help her enter your lactating herd earlier and therefore make you a little more money.
Sandra (00:05:18):
And so that's the decreased age at first calving, which is an economic benefit to you. And even longer term, there are at least a couple of studies that document improved milk production in the first second lactation. So it's not just the short-term benefits, but the longer term benefits as well that are gonna benefit you economically. So if you're trying to motivate yourself to do a good job with that first colostrum feeding, which takes, you know, maybe five or 10 minutes at most, there are lots of ways that you get paid back. And what is that economic benefit? There was a relatively recent meta-analysis, a study that looked at a number of different colostrum studies and tried to, to estimate the cost of a case of failure, of transfer passive immunity. And they estimated it to be roughly 70 US dollars per case.
Sandra (00:06:07):
But I should mention that that economic analysis only looked at the short-term benefits. They didn't also factor in the long-term benefit. So that 70 US dollar benefit is probably an underestimate of the true cost of a case of failure, passive transfer. So the bottom line is we should be well motivated to do a good job here. Now, what is the incidence or occurrence of failure of passive transfer in US dairy herds over the decades? The USDA nom studies, which get run every, every 6, 7, 8 years or so have gone out and bled many thousands of heifer calves on US dairies and measured the incidence of failure of passive transfer. Back in 19 91, 40 1% of heifer calves failed. So two out of every five heifer calves failed. By 2007 that had dropped to roughly one in every five heifer calves failing. And in the most recent study, 2014, that had dropped to 14% failure rate. So on the whole, as an industry, we have been getting steadily better at this, but there are significant opportunities that remain. And so we're gonna talk about how do we measure that, and then how do we address those opportunities going forward?
Sandra (00:07:24):
So if we wanted to build a comprehensive colostrum management program, I distill it down to these five cues: quality, quantity, and quickness. I'm sure you've all heard about before and we will revisit today. But in the last decade or so, we've added a couple of cues. One is squeaky clean or bacterial contamination, cleanliness of the colostrum. And then the one at the top of my list here is quantifying or measuring or monitoring passive transfer. So I'm sure you've all heard the old adage, we can't manage what we can't measure. We have to be able to measure this for colostrum management. So we're gonna talk about how to do that first, how to monitor passive transfer and co management in your herd. And if you're doing well, according to your goals and industry goals, fabulous, that's great. You can move on and find another bottleneck to work on.
Sandra (00:08:14):
But if you're not quite up to snuff or up to whatever your goals are, then we wanna visit the quality, quantity, quickness and cleanliness, and see if there are opportunities there to make improvements. But let's start with monitoring. So in the perfect world, we would have an on-farm serum IgG test that could be run very quickly on whole blood, really cheap, really fast to do. And the reality is, unfortunately, that test does not exist. So in research studies, yes, we will send serum samples off to reference labs and, and pay to have serum IgG tested. And anything greater than a 10 is considered a pass. However, on a farm, that just doesn't make sense. So on farms we use indirect tests such as either serum BrickX readings or in this graph you're seeing here, serum total protein readings. And in the first week or so of life, we know that serum total protein is going to be positively correlated or associated with serum IgG.
Sandra (00:09:14):
And if we're looking for a serum IgG of 10 or greater, historically, the literature has said that a serum total protein of somewhere between 5.0 and 5.2 grams per deciliter most accurately predicts that IgG value of 10. But you can see looking at the scatterplot, and this is from some Minnesota data from a number of years ago, there's not a perfect correlation here. Not all of those little blue dots are lined up on the black line. There is some scatter, which means an individual cath level. There could be false positives or false negatives. If we're looking at the serum total protein value, so instead of looking at an individual calf, we prefer to look at this serum pill protein data at the aggregate level, looking at the group or the herd and ask if the proportion of calves is passing or failing?
Sandra (00:10:05):
Acceptable. And then it, so what they were for, we're using this as a herd level or group level monitoring tool. So our old goal would be to bleed 12 or more clinically normal calves between one and seven or one and eight days of age, you or your veterinarian separate the serum and then do the serum total protein test or the serum bricks ref reflectometer test. And the old goal would be to simply have in my books a 90% pass rate. So 90% of calves tested would be at or above a total protein of 5.2 or a Brix reading greater than 8.4. Excuse me, Sheila McGirk in Wisconsin, retired now, but an awesome woman, very knowledgeable. She used to suggest that 80% of calves should have a total protein of value of 5.5 or greater either way. I think we're in the same ballpark.
Sandra (00:10:57):
And, but again, we're, we're looking at the proportion just passing or failing. And that's fine. And, and if you haven't done any testing yet, and you wanna start, this is a good place to start. But there were questions coming from the field you know, is higher better if I'm constantly getting in the sixes or the six point fives or total proteins, is that better? And is dichotomizing the data into a simple pass fail to be simplistic? So with that question in hand, and this is an example of a really good question coming from the field Jason Lombard, who was with USDA noms in Fort Collins, Colorado up until recently, he's now working for Carl, excuse me, Colorado State University. Jason settled a camp, a panel of calf experts from around the country. That group reviewed key papers in the last 10 years, and then Jason also had access to the most recent NOM study data.
Sandra (00:11:50):
So from 2014, over 2300 calves sampled from over 103 farms. And with all of this in mind, they asked the question, is hire better? And if so, what would our new goals be? So after looking at all of the data I'm gonna show you a survival curve. This is looking at mortality in calves broken down into different groups based on their serum immunoglobulin G levels. And we're looking at mortality in a period from birth to weaning at roughly 60 days of age. And so we have four categories of serum IgG here, poor or a fail is less than 10 grams per liter. So that cut point is not changed. Less than 10 is a fail, but in the past, a zone greater than 10 grams per liter, Jason and Natalie actually broke it into three categories. Fair being 10 to 18, good being 18 to 25, and excellent being 25 or greater.
Sandra (00:12:48):
So looking at mortality risk, we can see that mortality risk is definitely greatest. In the fail group, the calves with serum IgGs less than 10 grams per liter, that's the brown line in this graph. But we can also see that if you can get up above the fair and into either the good or the excellent range there is a further reduction in mortality. So that suggested higher is better looking at a similar graph, but now we're looking at morbidity or disease risk in the same period. You can again see with the brown line morbidity risk is highest if serum IgG is less than 10 grams per liter, the calves that truly failed. But we can see a further risk in reduction for disease if we can get the serum IgG up into that excellent range of 25 grams per liter or higher.
Sandra (00:13:37):
So this supported the notion that yes, higher is better, and maybe we should be looking at these perhaps four categories instead of just a pass fail two categories. So Jason published his data a couple of years ago, and now what we're advocating for is an industry for monitoring is four categories of serum IgG. Again, a fail is still 10 grams per liter, and we want fewer than 10% of calves to fail. So that really hasn't changed. And the pass would be greater than 10 grams per liter and 90% or more of calves to pass. So that hasn't changed. But now in that past category, we're breaking it into the fair, the good or the excellent range, and we don't expect herds to achieve a hundred percent of calves in the excellent zone. But in the middle column here, you can see the proposed proportion of calves tested that would fall in each category.
Sandra (00:14:31):
So we're suggesting in the top herds, we were seeing more than 40% of calves in the excellent zone in a roughly 30% of calves in the good zone. So this is what we're promoting in terms of monitoring and, and goals in your hertz. And again, if you haven't done this before, you could start with the simple pass fail, but if you wanna, you know, really shoot for the stars, then, then see how many or if you can get more cats up into the good or the excellent zone. Now again, we're not measuring serum IgG on farms, we're measuring serum total protein or serum BrickX readings. And so in the right two columns, I've shown the ranges for either serum total protein levels or the serum bricks levels, if those are the tools that you are using on your farm. And just as a way, I thought this is a pretty cool graph, this is a histogram that a veterinarian in Wisconsin used to describe how one large herd she was working with was fairing calves.
Sandra (00:15:32):
This is a large herd, so they were bleeding calves every week. And so over the course of a year, she plotted every week the calves that were in the good sorry, the excellent, the good, the fair or the poor zone, the poor being the blue fair being red, good being green, and excellent being purple. And you can see from week to week there's, you know, variation, which we expect in any herd. But overall, this herd was doing a really nice job of getting you know, a majority of calves upwards of 80% in the excellent and good zone combined. You could look at the data differently if you wish. I just thought this was a, a kind of a cool way of looking at it and, and very quickly grasping how the herd was doing. So that's monitoring. And if you haven't done anything monitoring yet, I would encourage you to have a chat with your vet about doing this.
Sandra (00:16:18):
Your vet can collect samples when they're out further, you know, biweekly herd check or monthly herd check, whatever the case may be. Or if they've got certified veterinary technicians working with you, the vet tech could sample the calves and, and do this testing. Or if you've got a large dairy, you could probably get your herd veterinarian to teach you how to bleed the calves, and you might be able to run these tests on your own. All right, so let's pretend for a minute that you've done some monitoring and you're not happy with your results. You wanna do a little bit better. So let's look at the quality, quantity, quickness and cleanliness. So we'll start with quality. So quality refers to the concentration of IgG in the colostrum, and experts have suggested that, whoops, excuse me, moderate or higher quality should be at least 50 grams per liter or higher.
Sandra (00:17:11):
Now this is a scatter plot from some Minnesota data from a while back, 125 cows here from 12 different herds. And what we're looking at is the quality of Closs IgG on the horizontal axis. And then on the vertical axis is the calf serum IgG for what was measured in the calf that was fed a particular Eloqua colostrum. Most of these calves are fed four quarts within a couple hours of birth. So we can see the predictable positive relationship, the higher quality fed, the higher the serum IgG level reached in the calf. And that's just a question of math. More grams fed equals more grams absorbed across the gut into the calf circulation. So that's no surprise. But I think the other interesting thing to learn from this scatterplot is to look at the variation in colostrum quality in these 12 herds. Maybe, I don't know, 25% of cows are failing.
Sandra (00:18:04):
Corum IgG is less than 50 grams per liter, and yet other calves have that liquid goal that we're referring to earlier you know, a hundred grams per liter or even pushing 150 grams per liter. And so I think the interesting question is, what can we do or what can you do as managers to manipulate how you manage those cows in a way that gives you more high quality colostrum? Looking at the most recent nom study, this is the colostrum quality measured from all of the herds tested. On average, 77% of samples were good at 50 grams per liter or higher. And on average, the mean colostrum quality was an IgG roughly 75 grams per liter. So on average, you know, that's not too bad, but there's a higher proportion of samples failing here than I would like to see, so that, again, there's an opportunity for at least some herds to improve.
Sandra (00:19:02):
Now, how do we manage or manipulate classroom quality? There are several factors that we can address that are in our control, that are under our control. I've just listed a few of those here. First of all, looking at the dry cow vaccination program, and here specifically I'm referring to the vaccines that we can use in dry cows that cause her to produce more antigen-specific antibodies against the scours pathogens. So e coli, rotavirus, and coronavirus. Now, you should know that if you start, if you adopt a scours vaccination program in the dry cows, you're not gonna see a dramatic bump in your colostrum quality as measured through either a BrickX or co trotter. It's more subtle than that, but if we did test your colostrum for antigen specific antibodies to equal eye levels would be higher. So I still think that's a valuable management strategy.
Sandra (00:19:56):
Other things feeding a balanced dry cow rations. So vitamins, minerals, trace minerals, energy, you know, dietary energy, protein and the like. And then promoting good dry matter intakes are going to be important. Avoiding stressors during the dry period, heat stress overcrowding and the like, frequent transports. These are gonna be things we wanna do for the cows benefit anyway, but are also gonna benefit chorum quality. And then avoiding excessively short dry periods. Anything less than 21 days dry, she will produce neither the quality or the volume that you need. So cows that you know, are drying off with twins if they're carrying twins, dry them off a couple weeks early because you know that they're gonna calve a couple weeks early. And then finally milking cows out as soon as you can after calving, you're gonna get higher quality colostrum harvested.
Sandra (00:20:50):
So ideally within one to two hours maximum of six hours. And even if you've, maybe you're a smaller herd and you don't have round the clock labor, you don't have the ability to harvest colostrum from every cow. You know, even if she calves in the middle of the night, I would still try to get them milked out the first thing in the morning, and that's where the maximum of six hours comes in. If you can achieve that in, let's say 90% of your cows get milked out within six hours, I think you're in pretty decent shape. But before you get worried about, you know, should I go and look at these, these management strategies, first of all, just do some monitoring of your colostrum quality. So you could use the old glass colostrum trotter, which never really got widely adopted in herds. You know, there's some issues with it, it's not perfectly accurate.
Sandra (00:21:34):
It is impacted by things like colostrum temperature and its glass in a barn, which in my experience with vet students anyway, is not always a good combination. So more recently we've, we being, you know, colostrum researchers have done studies of the BrickX refractometer and it's measuring total solids, but it is positively correlated with IgG concentration in the colostrum. And it's reasonably accurate. It's not perfect, but better than the coter. And so different studies have been published, you know, what, what's the bricks cut point to predict a colostrum IgG of 50 grams per liter or higher? Most studies point to roughly 22%, although there's been a little bit of variation in the exact cut point ranging from 19 to 22%. So my goal: if you're doing some herd level testing, you know, every cow that calves you, you quickly test her with the bricks refractometer.
Sandra (00:22:30):
My goal would be for at least 90% of your cows or samples tested to test with the bricks reading 22% or higher. If you're doing that, you are in really good shape. If you're not, let's say you've got 50% of your samples are under 22%, then I would go back to this management list and see if there are opportunities to tweak any of those factors. So that's quality. Tied in with quality is volume produced. So I'm taking a little bit of a tangent here to talk about volume. Right now, this time of the year is a frustrating time for many herds that observe a lower volume of colostrum produced by the cows as we enter the fall and early winter months. Now, the quality may be fine, but maybe they're not giving that, you know, four or five quarts that you're used to in the spring and summer months.
Sandra (00:23:21):
And so the question is, what are the factors affecting this lower volume in the fall and winter months phenomenon that we, we, we don't always see thankfully, but a lot of hertz do experience it. So there was one large study done, I'm gonna show you the results here. This is a Texas herd jersey herd that measured volume over the entire year from every cow that calved. And then they investigated what factors either cow level or seasonal or other herd level factors, were associated with producing a low yield of colostrum. The cow factors included lactation lengths, short days, dry cows carrying twins, and older cows were more susceptible to decreased volume, but more interesting, like we knew about some of that. But really interesting is this seasonal effect that we're seeing in this graph. So the horizontal axis is the week of calving. So week 51 is roughly Christmas time, right?
Sandra (00:24:18):
So that's as we approach the end of the year. And then week two, you know, we're two weeks after New Year's day, and then we head, head out into the spring. If we look at the black solid line here, that's the colostrum volume produced. So you can see as we enter the fall months, and I guess the Nader is right around Christmas or New Year's Day colostrum volume on average is at its worst. And then we climb outta that as we head into the spring months. Again, the dotted line that you see above that is the temperature humidity index. So the cold weather, obviously you know, temperature is falling towards Christmas in the new year, and then the increases again towards spring. And then the hatched line is the photoperiod or day lengths. So what this study described was an association between the season, the drop in the temperature, as well as the drop in the day lengths a photo period were both correlated or associated with the drop in colostrum volume produced.
Sandra (00:25:20):
Now, we don't know for sure is the temperature is, is it the day length? Is it a combination of the two? We don't know for a fact what the factor is that's driving this decrease in colostrum volume, but it's real and other, other studies since or actually, yeah, actually there's two studies since I referenced at the top of this slide. S Larry in 21, Rossi in 22 that observed the same seasonal effect or relationship. Now, one limitation of this Texas study was they didn't evaluate nutrition because it was only a single herd and all cows were fit the same ration. So it's possible that nutrition or interaction between nutrition in the winter months, the colder months could come into play. And so nutritionists make sure that you're feeding adequate energy and adequate metabolizable protein, 1200 grams of metabolizable protein or more in your dry cow diet.
Sandra (00:26:17):
But until we figure this out and find a solution, what's the short term solution? Well, it's to bank colostrum to freeze surplus colostrum during the spring and summer months when you have a surplus in preparation for a possible shortage in the fall and early winter months. Or you could default to using colostrum replacement products if you do run short. But either way, be prepared for this. Okay, now I'm diverting back off my tangent back to my five Qs, and we're gonna talk about quantity next. So the question is, what volume colostrum should we provide particularly at that first feeding? And, and it's kind of a trick question. The answer is really, well, it, it depends on, you know, what's our goal for the mass of antibodies we wanna deliver to the gut. The minimum we wanna deliver is 150 to 200 grams of IgG to the calf on average.
Sandra (00:27:10):
For the average calf, I wanna get about 300 grams of IgG into the average calf. So minimum 150 to 200 on average. If I've got decent quality colostrum, I'm going to be delivering about 300 grams or more. So the question is really what volume should we provide at first feeding to get a minimum of 150 to 200 grams or an average of 300 grams of IgG delivered to the calf? And the answer is of course, well, it depends on the quality, but typically we don't want people doing math in a barn. So what do we do? We hedge our betts by just simply feeding an adequate volume and assuming that quality is meeting our goals, you know, 90% with a bricks reading 22% or greater. If we feed four quarts, 3.8 liters to a typical Holstein calf or 10% of the birth weight to the calf, if we're feeding and it's decent quality, we are gonna be getting that average of 300 grams into the average calf.
Sandra (00:28:07):
Now how do we deliver 3.8 liters or four quarts to a typical Holstein? Because we know calves won't voluntarily consume that large volume, at least most cats won't. A Holstein calf on average will consume two to two and a half quarts voluntarily. Well you could either use a nipple bottle or an esophageal tube feeder. The advantage of the tube feeder is it's quick and we're gonna get that volume in very quickly. Bottle fed calves that work great too, but you may need to be prepared to come back and deliver a second feeding a few hours later if the calf doesn't voluntarily consume that full 3.8 liters. The bottom line is either approach works well, you just have to get the volume delivered. Training and equipment cleaning conditions are important, whether it's tube feeding or bottle feeding. And if you are tube feeding, I would just caution, I don't like to see calves tubed multiple times. Many herds will tube twice and then af at the third feeding, they're gonna switch over to either nipple bottle or bucket feeding, and that's fine. I just don't want people doing prolonged multiple tube feedings or we're gonna eventually run into gut problems.
Sandra (00:29:23):
Now the quantity delivered is a study done sometime ago that fed either two liters at first feeding or four liters at first feeding. Two liter group is in pink, the four liter group is in green. And both, both treatment groups provided a second feeding at 12 hours of two liters. But basically we're looking at the difference in serum IgG over the first 48 hours. And you can see if we provide the high volume, the four liters at first feeding, we're simply delivering more grams of IgG into the gut. So it's no surprise that we see a much higher serum IgG level in that group. So bottom line is at that first feeding, it's important that we get the good volume in there. And again, back to whether it's a nipple bottle or esophageal tube feeder, it doesn't matter provided you get the volume delivered. So this is an example of a tube versus bottle study. Both groups were delivered three liters of colostrum replacer sub to 200 grams of IgG in either group. And over the first 48 hours we can see the serum IgGs in these two groups are identical. So I really don't care whether you use a bottle or a tube, just get the volume in there. That's what's important.
Sandra (00:30:35):
Okay? And that brings us to quickness. And I'm sure you're all familiar with this concept of gut closure. So when the calf is first born, the epithelial lining of the intestines are such that it allows the absorption, the movement of these large protein molecules, these IG molecules across from the lumen of the gut into the circulation or the blood of the calf. But over that first 24 hours of life, the lining turns over, it changes such that the calf loses its ability to absorb the antibodies. And so we call this process closure and we consider it to be finished. Or the door is closed, if you will, by 24 hours of age, give or take a few hours. So in this figure that I've shown in the lower right hand corner of this graph, you can see the efficiency of absorption of IgG is optimal in the first couple of hours after birth, but then slowly is reduced.
Sandra (00:31:30):
So this means that of the grams of IgG we've delivered to the gut, this is the percent that will be absorbed. And even right outta the chute, it's only 30, 40, maybe 45% at best, but it's going to progressively get worse the longer we delay feeding. So the bottom line is we wanna feed the calf as soon as possible, ideally within one to two hours at birth. But again, I recognize not everybody is round the clock labor. Not everybody can do that. But again, I'd like to get, you know, a goal of 90% of calves dead by six hours outside. And if you need convincing that this age of feeding or time to first feeding matters, this is some data from a really nice study outta the University of Guelph where calves were randomized to three treatment groups. The first group was fed 45 minutes after birth, the second group was fed six hours, and the third group was fed 12 hours after birth.
Sandra (00:32:23):
And what we're looking at here is the serum IgG over the first 48 hours of life. And you can see it's significantly higher in the group of calves fed within 45 minutes as compared to either the six hour or the 12 hour group. And when the investigators calculated the apparent efficiency of absorption of that percentage of IG delivered to the gut that was absorbed into the blood, it was 52% in the 45 minute group, but only 35 or 36% in the six or the 12 hour group, which is what explains why they didn't achieve the same peak peaks or my GG levels. So delaying even for six hours does cost us. So the bottom line is try to get that colostrum, excuse me, delivered as quickly as possible.
Sandra (00:33:10):
So we've been talking about that first feeding colostrum and focus mostly on that. But a really good question that comes up is, is there a valued offering, a second feeding or even additional feedings in the next day or two or three even if the gut has closed, even if the calf can no longer absorb the antibodies into the circulation? And the short answer is yes. And if, if, if it can be implemented easily by your pharm, it's practical to implement, I would encourage farms to consider doing this. So I'm gonna show you the results of one study. This is another study of the University of Guelph. All calves are fed the first feeding colostrum that was same across the groups, but then the calves are randomized to one of three different colostrum or milk diets for the next three days. Fed two quarts twice a day.
Sandra (00:33:58):
And the three different colostrum or milk diets were as follows. One group was fed pooled heat treated colostrum. So first milk and colostrum for the full three days. The next group in the middle was fed a one-to-one ratio of colostrum and whole milk. So that's kind of the same as transition milk, think of it that way. And then the third group was just fed whole milk for the next three days. Now at the end of the three days, the calves are sacrificed and then they looked at the development of the gut. So we're looking at a cross-section of the small intestines and the development of vii that this is our absorptive surface area that is going to be absorbing nutrients to feed the calf. So we can see very quickly that we have superior gut development in the group A or B as compared to C.
Sandra (00:34:46):
So the pool heat treat colostrum or the transition milk group, the B group we saw significantly improved gut development. And I'm not gonna show you the results. There's a different study again that described the impact of this on growth. This simply fed this for three days and there was a significant growth benefit just within three days that lasted through the whole pre-weaning period by feeding either colostrum or transition milk equivalent for that first three days after, after birth. So even three days of transition milk is gonna be beneficial if you can manage it. Now what about this question? What if we could supplement the milk diet with either colostrum or transition milk for longer for maybe up to two or three weeks? Then what? So I'm gonna show you a few different studies that did this. So this first study here, all cancers fed a milk replacer diet.
Sandra (00:35:45):
We've got a control group, a placebo group, and then the treated group had a colostrum supplement added to the milk replacer at a rate of 10 grams of IgG per feeding. And they fed this over 14 days. And what we're looking at here is a proportion of days with scours. So we can see a significant reduction in the number of days with scours in the group of calves where there was a colostrum supplement added to the milk replacer Next study, very similar design. We've got a control group and a group where colostrum supplement is added to the milk replacer this time at a higher dose, 32 grams of IgG added to the milk replacer over a 14 day period. And now we're looking at the pre-weaning incidence of scours, and you can see a significant reduction, fewer than 2% of calves scoured in the supplemented group versus almost 17% of calves in the control group.
Sandra (00:36:35):
And finally, if you didn't wanna add colostrum supplement, but you wanted to add transition milk which I think is a very viable option, I would encourage it in herds that are feeding pasteurized milk to add transition milk into your pool. In this last study, we've got four treatment groups. All are fed a total of six liters a day of the milk diet. The control group is six liters of pasteurized milk. That's the bar on the right hand side of the graph. And then moving to the left, we proportionately the investigators increased the proportion of the six liters that was transition milk. So instead of six liters, the next group to the left is five and a half liters of pasteurized milk, plus half liter of transition milk. The next group to the left is five liters of pasteurized milk plus one liter of transition milk.
Sandra (00:37:24):
And then finally, the group to the left is four liters of pasteurized milk plus two liters of transition milk. And what we're looking at here is the duration of the scours event. So if you experience scours, how long did it take you to recover? And you can see the recovery rate was much quicker in the group that had the greatest proportion of transition milk in their milk diet. So summing up the results of all of these studies, and there are others that I'm not showing today. There are studies that document a reduced incident and duration of scours, improved growth rate, reduced respiratory disease incidents, and reduced antibiotic use through the practice of supplementing the milk diet with either colostrum supplement or transition milk. So again, if your herd can accommodate this, and I realize it's not always practical to do so, but if you can, this is an intervention that you could consider adopting that might benefit your calf health and growth.
Sandra (00:38:19):
And that brings us to our last queue, which is squeaky clean or cleanliness. We're talking about bacterial contamination in colostrum. So why should we care about feeding clean colostrum? The first reason is we don't wanna feed colostrum that is laden with pathogens that can cause disease. Bacteria like e coli seminal or mycoplasma or mycobacteria impaired tuberculosis. That's the organism that causes you to use. Obviously we don't wanna be feeding these organisms to calves in dirty colostrum, but the other reason we wanna feed clean colostrum is this phenomenon here. The second point is that high bacteria counts in colostrum have been associated with reduced absorption of IgG. And this has been documented in several studies. The scatterplot I'm showing you here is one of our larger studies. There's over 1000 calves here. On the horizontal axis is the log of the coliform count in the colostrum that was fed.
Sandra (00:39:13):
And the vertical axis is the resulting serum IgG level in the cat that was fed that particular aliquot of colostrum. Now, there's a lot of scatter in the scatterplot for sure, but there is a significant negative relationship. That red line shows the higher the co form count in colostrum, the lower the resulting serum IgG level. So somehow those bacteria are binding, blocking, interfering with IG absorption across the gut. Now, what would clean colostrum be? Now if we're talking about raw fresh colostrum, not heat treated, our goals should be a total plate count or TPC less than a hundred thousand CFU per mil and a coliform count TCC less than 10,000 CFUs per mil. And those recommendations come from Sheila McGirk and Sam Ledley. Now for feeding heat treated colostrum, my goal from a total plate count is less than 20,000. So it drops significantly.
Sandra (00:40:03):
We expect it to be cleaner yet, but in a national study there were 800, over 800 samples of colostrum cultured from 67 herds in four different regions of the country. 43% of the samples tested exceeded that total plate count of 100,000. So at the industry level, there's a big opportunity for us to do a better job cleaning up the colostrum that we're feeding. So how do we do that? Well, we need to look at the different places where bacteria can be introduced and, you know, intervene at this control point. So the first would be the cow. So if you're testing for yonis or map and you know you've got a suspect or positive cow, obviously we don't wanna feed that colostrum to a heifer calf. Similarly, we don't want the calf suckling the dam because it's going to be getting dirty, you know, manure pathogens off the tee skin.
Sandra (00:40:55):
We wanna prep the utter, disinfect the utter very well before we harvest the colostrum so that it's clean. And then if we are feeding raw or fresh colostrum, not heat treated, we don't want to pool colostrum, we wanna use a one cow to one calf rule. That way, even if there was something that the cow had shed, we're gonna minimize the number of calves exposed. The next control point is cleanliness of the equipment that's used to harvest, store or feed the calf. So pay attention to that, look at that. And if, if it's dirty or if you're not sure, have your veterinarian or a specialist, a consultant come out and evaluate cleanliness. If it is too dirty, then you can look at your protocols and training to clean that up. Finally, bacterial proliferation in stored colostrum can be a problem. So this is this colostrum that's been collected.
Sandra (00:41:47):
It sits around for too long or under improper storage conditions and the bacteria start to multiply. So how do we avoid that? You can either one, just feed the colostrum within an hour or two of harvest, and then the bacteria never get a chance to start multiplying. Two, you could refrigerate it very quickly after harvest, but I want you to use it up within two days. If it is refrigerated or three, you could freeze it and then it's good for a year or more. Or finally, you could use preservatives like potassium sorbate, which will get you an extra one or two days of shelf life in refrigerated stored colostrum. So this list of strategies is, I think, interventions that all herds can use. None of them are very expensive. And this is where I would look first to clean up my colostrum. Now colostrum replacement, excuse me, replacement products or heat treating are additional tools that are definitely appropriate in some hertz replacers very quickly, you know that these are products with a minimum of a hundred grams of IG per dose.
Sandra (00:42:49):
They tend to be a little on the expensive side, you know, 30, 35, 40, 40 $5 per dose. The IG in the colostrum replacement product could be either from lacteal sources, so spray dried colostrum, or it could be serum or plasma derived. Obviously it includes nutrients and these products are useful to replace maternal colostrum. One, maybe it's the middle of the night and you just want to go back to bed. So it's convenient to grab a package mix and feed it very quickly if you can't harvest from the dam. If you don't have an adequate supply of maternal colostrum in storage, or another place for these products are infectious disease control programs. So for example, you've got the unis positive cow or a suspect and you wanna feed one of these products instead. That's a perfectly reasonable strategy. So I think that all herds should have some of these products sitting on the shelf, you know, just in case.
Sandra (00:43:44):
I do recommend that you reconstitute these products in water according to the label. Before adding it, let's say you were adding it to the maternal colostrum. We don't want to add it dry to maternal colostrum or you can create a hyperosmotic solution. The solids are just too high and that can interfere with gut motility and IG absorption. So I would recommend mixing according to label and water first and then and then feeding. Now it's important to understand that the dose of IG that you deliver in these products matters. You know, the Lalo replacer one dose bag a hundred grams of IgG, it's a very, very good product. But if we only feed a hundred grams, what I'm showing you here in this graph results from Minnesota data: fewer than 50% of our calves are gonna pass, or we're not gonna even meet the average serum IgG of 10 grams per liter.
Sandra (00:44:41):
That is our minimum for a pass. Now, if we feed one and a half doses, 5% of calves failed. If we fit two doses, 200 grams of IgG, nobody failed. But if we remember back to, you know, feeding high quality maternal colostrum 3.8 liters averaging you know, three, it's gonna be 80, 85 grams per liter, we're easily gonna deliver an average of 300 grams of these caps. So producers should not be astonished if they feed only a hundred grams and we get lower passive transfer rates with these replacement products. It doesn't necessarily mean the product is a bad quality product, you just need to feed a higher dose. So that's the decision you need to understand heat treating very quickly. This is another way to clean up colostrum. And we're seeing over the years progressively more and more herds adopting colostrum heat treatment programs, more so in the large herds than in smaller or media sized herds.
Sandra (00:45:37):
But in more recent years we are seeing cheaper systems developed that can be adopted even on smaller herds. So what we're doing here is we're taking fresh colostrum on larger dairies. You're gonna pool it once or twice a day into a batch heat, treat it at 140 Fahrenheit or 60 centigrade for 60 minutes, cool it back down quickly, and then put it in a clean bottle or a single use disposable bag, and then either refrigerate or freeze and then warm and feed as cats are born. If you don't have large volumes to do, you know, pools every day, you can heat treat individual bags of colostrums. There's three quarts, four quarts from individual cows. And that works perfectly well as well. So does this result in healthier calves? We've done two large, whoops, two large studies now.
Sandra (00:46:30):
I'll just show you data from our first large study where calves on six different Minnesota or Wisconsin herds were randomized at birth to be fed either 3.8 liters, fresh colostrum, or 3.8 liters heat treated colostrum. We enrolled over 500 calves per treatment group, and looked at a number of different outcomes. I'm just gonna show you the health data here, but looking at the incidents of death or disease incidents in the pre-weaning period, fresh calfs, fed fresh colostrum is in blue, heat treated colostrum is in the maroon. We can see looking at scours incidents and overall incidents of all kinds of disease, there was a significant reduction in morbidity fed to heat treated colostrum. So the bottom line is feeding clean colostrum is definitely beneficial to our calves. How do you get there? Start with the motherhood and apple pie stuff first, but then replacers, excuse me, replacers can be useful tools and heat treating can also be a useful tool.
Sandra (00:47:32):
So just to summarize, cluster management is a cornerstone of a successful replacement program. And on the average herd, there is still an opportunity for producers to improve colo management, thereby improving calf health and future performance. And very quickly, again, the five Qs are listed here. And if there are any questions, I guess I would be happy to take any questions. Now very quickly before I stop showing, I'll just acknowledge various funders who have supported our research over the last many years. And I also want to thank all of the various farms that have helped us out with our studies as well. So thanks again.
Kim (00:48:19):
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Sandra (00:49:23):
That is an awesome question, Bethany. Thanks. yeah, I should have mentioned that. Yes, if the calf gets dehydrated, your serum total protein can look artificially higher than what it truly is. So where do I get suspicious? In the low eights to eight and a half, I'm starting to wonder. So if you have one or two, you know, eight point twos in your whole group, that's fine. But, but you know, eight, eight and a half or higher, I'm starting to get nigy. And I wanna ask, you know, how was that calf looking when we, when we sampled it? Some work from the University of Guelph documented that calves can be, they can scour with mild scours and so you know, they'll be mildly dehydrated and that won't impact your results, the accuracy of your STP result.
Sandra (00:50:12):
But I would, I would be wary of really sick calves, you know, you know, really obvious sunken eyes depression. I would, I would avoid those calves. So yeah, that, that would be my cut point for being suspicious. Bethany also, I should mention I, I didn't mention this in my talk, but checking the calibration of your instrument frequently is wise too because STP refractometers can become uncalibrated. So your veterinarian can do this for you but just check it periodically to make sure that it's calibrated properly. 'cause That could give you erroneous results one way or the other. Yeah.
Kim (00:50:55):
Excellent. Pete is asking, what's the average colostrum volume collected at First harvest?
Sandra (00:51:03):
Typically around four quarts or between four and five quarts is average. In most studies cows will give a little bit more than ca heifers versus calf heifers on average. But, but we, we hope to get a gallon on average.
Kim (00:51:21):
Okay. And Jorge is asking how many days after calving do we consider the milk to be transition milk?
Sandra (00:51:28):
Yeah. so the first milking colostrum is first milking, then second through the fourth or the fifth milking is considered transition milk. So by the third day, certainly by the fourth day that's, that's regular milk. No longer transition milk.
Kim (00:51:46):
So here's an interesting question from beak. It might be from our international audiences. How would you best manage colostrum and herds where the calf must stay with the cow for a minimum of 24 hours? The calf will suckle at the cow. Often we'll give four liters of quality colostrum within four hours of birth.
Sandra (00:52:06):
Okay. So I can't ask him a follow-up question probably, but he, so the, the calf is suckling plus they're delivering four liters,
Kim (00:52:15):
That's what it looks like.
Sandra (00:52:16):
Yep. Within four hours. That sounds like an awesome program to me. If you're able to achieve that, that's great. If you're, if what he meant was the calf is suckling and they're assuming it's getting four liters through suckling, that is hmm, questionable. And that's where bleeding some calves, sampling some calves, testing some calves will give you the answer, how is your program working? Yes or no? But if it's the calf, so if, if they weren't doing that, if the calf, if they were just relying on the calf suckling, what I would say is fine if the calf suckles the cow. But I would still hand feed the calf at minimum two liters as soon as you can. And if, if he's, if they're getting four liters in within four hours, that should be awesome. But again, go ask the calves, bleed some calves, they'll tell you the true picture.
Kim (00:53:05):
Okay, perfect. Joe is asking, regarding the number of calves to test, why test 12 calves depending on the size of the farm, what's your advice in relation to how frequent to perform this on the firm?
Sandra (00:53:16):
Yeah the number of calves, we don't wanna get into a lecture of epidemiology. Our students' eyes roll back into their heads. Oh my gosh. But it, it, it comes down to we're we're estimating a proportion what percentage passed, and we have confidence intervals around that proportion, you know, with 90% past, but how confident we are, we, the 90%, the more calves you test, the more precise our confidence intervals will be that it's truly 90% or whatever our result is. So 12 is like the minimum. Our confidence intervals around your estimate are still pretty broad, but it's like the minimum. But if you wanted to test 15 or 18 or up to 20, you're going to get more precise estimates of the actual, true proportion. You know, is it 90% passing or whatever. So that's, it's an epi exercise in math that came up with the 12.
Sandra (00:54:09):
But if you've got more calves and you can do 15 or 20, that would be great. 12 is the minimum. As for how frequently you should test, I guess that depends on your, your herd size and you know, a small herd. It might take them one or two weeks to get 12 calves. You know, so testing like once a month if you know, that would be, that would be ambitious. Larger herds that have gotten more calves born in a given week or given day, you might test weekly. Yeah, the very large herds are testing a subset of let's say 20 calves once a week just to monitor how the herd program is doing. And I'm sure you're all aware some contract heifer growers that are receiving calves will oftentimes test a random, you know, 15 or 20 calves per load coming from a dairy from a source farm just to make sure that the program is working. Other contract heifer growers might test every single calf because they know that what that calf comes in with definitely impacts its performance, not just that calf, but the whole herd immunity for the heifer grower. So so yeah, the frequency, you know, let's say once a month down to once a week depending on your herd size.
Kim (00:55:22):
Well, and another interesting question from Jennifer kind of is a good follow up to that. What advice do you have for veal producers who are purchasing calves? What's the best feedback we can provide dairy farmers were buying calves from, and where should we focus our discussions?
Sandra (00:55:38):
Yeah, that, that's a great question, Jennifer. And, and okay. I'm not sure what a veal calf, a wet veal calf is selling for right now, but I know what a black beef on dairy calf is selling for right now, and it's a lot of money, you know, $400-$500. So these calves are worth a lot of money. It's important that they arrive, whether it's at the you know, if it's a beef grower or a veal grower, it's, I think, important that they arrive with adequate passive transfer. So, Jennifer, I would have the same conversation as a veil grower with my source farms as if I were a contract heifer grower. It's equally important to that calf, that farm. So have that conversation. First of all, you know, do some testing. If they're meeting their mark, great. Give them that positive feedback.
Sandra (00:56:29):
'Cause That encourages 'em to continue. And it tells them that you're looking, it tells 'em that you, you know, value this, that it's important. If they're not meeting the mark, then have a conversation about, you know, what, what are the opportunities? Why is this important to you? Perhaps have their veterinarian go out and do a walkthrough and what we've talked about this morning. See where there are opportunities to make improvements. I guess the worst case scenario I've seen, and hopefully this doesn't happen too often, is buyers will pay less for calves or there's a financial penalty to calves coming from certain sources or calves that come in that fail. Occasionally people will fire source farms if they just refuse to try to pull up their socks. So there are, you know, gradations to the conversation, but it's definitely worth paying attention to.
Kim (00:57:23):
So we're having a lot of questions coming in about heat stress, so heat stress reduces the quality and the quantity of colostrum. Do you have any, are you aware of those effects and how it impacts the volume and quality?
Sandra (00:57:38):
Yeah. dogma, there's not a lot, there's not a lot of really good research on it, but dogma has it that heat stress will, will negatively impact both quality and quantity. However, even though that's conventional wisdom, truthfully, there's not a lot of research supporting it. But I would still, it makes sense that it would, and so I would still try to mitigate heat stress for the dry cows, even if it doesn't even have anything to do with colostrum quality or quantity. It's so important to the cow. Like we, we've got multiple studies saying how mitigating heat stress in the far off and the closeup dry cap period has huge impacts on her future lactation performance as well as, and this, this epigenetic programming concept, it's programming the fetus that she's carrying the, the calf inside her. So we know it's some really, really interesting research where, where dry cows were given heat abatement or not through the dry period, and they looked at the weight of the calf born, passive transfer and health of the calf born, growth in the calf born and future milk production in that calf.
Sandra (00:58:54):
And it's all negatively impacted in cows that experienced heat stress, like when the dam experienced heat stress when the calf was in utero. And now there's research that says that, and that carries over into the next generation as well. So there's not a lot of research saying it negatively impacts quality or quantity a little bit. And anecdotally, yes, but even regardless of that and what the truth is there, I would still stress the importance of mitigating heat stress for other reasons.
Kim (00:59:25):
Yeah, that epigenetic data is just so exciting and all that can be impacted for several generations beyond. Mm-Hmm.
Sandra (00:59:49):
Okay, well, we can freeze at, you know zero degrees centigrade 20 degrees, I think that's 20 degrees Fahrenheit. Sorry if I get my conversion wrong, but you know, just a typical freezer and that's fine, just keep it frozen. And you said for how long?
Kim (01:00:09):
How long can it be frozen?
Sandra (01:00:11):
Yeah, dog, again, back to conventional wisdom says a year. I think what's, yeah, I'm, I'm happy with the year. I haven't seen, truthfully, I haven't seen data looking at it longer to say, where does it fall apart? I have pulled small volumes of colostrum or outed my own freezer after a few years, and when it looks dry and powdery, I'm thinking, eh, no. But anyway, up to a year. But within the year again, this is conventional wisdom. You don't wanna put it through multiple freeze thaw cycles. So if, you know, defrosting freezing, again, defrosting freezing again in my own work I've put colostrum through two freeze thaw cycles and didn't see a negative impact, but I still wanna be cautious about not, you know, taking that to the extreme. So just one year, typical freezer is fine and just avoids multiple freeze-thaw cycles.
Kim (01:01:02):
Excellent. And kind of a last question comes from Camilla. What do you think about possible differences concerning absorption of IgG among breeds and even between different Holstein strains or genetic lines?
Sandra (01:01:16):
Hmm, interesting question, Camilla. I have, I've not seen any data that directly compares IgG absorption. If you're talking about the efficiency of absorption in the gut, I'm assuming that's what she means. I, I, I'm not aware of studies that have compared that between breeds, so I can't say we don't, the goals for passive transfer that we have that I presented this morning, were derived with Holstein halves. There was one study on one farm that suggested maybe for jerseys we might like it a little higher, but it was only one study on one farm. So I'm hesitant to make too much of it. But, so for the moment, we'll just use the Holstein I'm recommending using the Holstein goals for, for everybody. Dairy breeds, not beef. That's different.
Kim (01:02:10):
Okay. Balchem podcast series continues to offer a deeper dive into our webinar topics. Log onto your favorite podcast platform and search for real science exchange or visit balchem.com/podcast. If you want a cool real science exchange t-shirt, just subscribe to the Real science exchange and send us a screenshot along with your address to anh.marketing at balchem.com and we'll get that off to you. On behalf of Balchem and Dr. Godden, thank you for joining us today.
Kim (01:02:41):
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