The Moos Room™

Brad
Oh, it is a crisp and cool September morning here in Minnesota. It's starting to turn to fall although we're kind of in a cold snap. I think it's going to get hot again next week. So it's kind of that weather changes. Where does it really want to be. Summer or is it turning to winter? I don't want to think about winter quite yet.

00;00;36;28 - 00;00;58;00
Brad
Our cows are still out on pasture. We've had lots of rain here. Even in the fall. There is so much grass that will be able to graze well into October without any issues whatsoever, which is kind of nice for once. Save a lot on the stored feed. We'll be getting to calves soon, so we're going to have lots of babies.

00;00;58;10 - 00;01;23;08
Brad
Talk about some new projects in the future. But today I wanted to talk about milk, fatty acids. I think it's one of the topics that's kind of gaining in interest from people. There's some groups that are working on it. I know I've been speaking on fatty acid profiles. I'm going to speak, actually, is Monday the day that this podcast come out?

00;01;23;10 - 00;01;54;15
Brad
Going to speak to some Dei lab managers from all over the US about fatty acids and how you might use those in dairy nutrition. Obviously, it's we've long focused on balancing energy and protein and fiber, but obviously a growing interest is milk fatty acid profiles. And now we can determine those a lot faster and a lot easier than what we have in the past.

00;01;54;17 - 00;02;23;26
Brad
So farmers can now track their milk fatty acids through routine milk testing, either with DHEA or a lot of milk processors have started to incorporate these into daily reports of milk, fat, protein, somatic cell count that we've seen in the past. They're now including those as fatty acids as well. Ours has not yet. We're with DFA, at least on our conventional herd.

00;02;23;28 - 00;02;57;03
Brad
I can look up our lab results, and I see there is space there for de novo mixed and pre-formed fatty acids, but there's no values there yet. So maybe once into the future I'll start seeing those for our herd as well. Let's dive a little bit into what milk fatty acids are. And then I want to talk about some of the research that we recently completed with a graduate student on milk fatty acid profiles from some commercial herds that we went to here in Minnesota, as well as our own University of Minnesota herd.

00;02;57;04 - 00;03;33;08
Brad
But first, obviously, we know that milk fat is composed of hundreds of fatty acids, but they're kind of grouped into three different fatty acid groupings. First is de novo fatty acids. And these are the C4 through C14. They're synthesized in the mammary gland from rumen fermentation. So the other makes these fatty acid profiles so higher. De novo fatty acid levels are often linked to strong rumen health and efficient forage digestion.

00;03;33;10 - 00;04;09;10
Brad
So the higher the de novo fatty acids, kind of the better off we are. What about mixed fatty acids. And these are C16 through C16 one. They're derived from both de novo synthesis and dietary fat. So a lot of herds can be adding palm oil or palmitic acid. And we've probably seen that from the most part. And that's been really associated with negative human health implications when that's elevated.

00;04;09;13 - 00;04;45;06
Brad
Now what about preformed fatty acids. So that's the other grouping. And those are the carotenoids. And longer they're mobilized from body fat reserves or can be provided directly in the ration. And elevated preformed often reflect early lactation. Negative energy balance. So we want to have lower preformed fatty acids at least as an indication of rumen health. But all of these fatty acids are a direct reflection of nutrition, rumen environment and cow physiology.

00;04;45;08 - 00;05;24;09
Brad
So nutrition has a big impact on fatty acid profiles. So rations that are rich in starch but low in fiber can depress milk fat. So lower milk fat and we can shift those through rumen fermentation and lower de novo fatty acids. So higher starch lower de novo and mix fatty acids while increasing the preformed fatty acids. However, diets that are high in forage and fiber rich tend to have higher de novo fatty acids, which support healthier rumen function.

00;05;24;10 - 00;06;05;08
Brad
Obviously, there's a lot of interest about strategic fat supplementation. Like I talked about. We're using palm oil, which can increase the levels of C16, which are the mixed well. Unsaturated fat sources can influence the C18 levels or the oleic acid. Obviously, seasonality matters as well. Previous research has shown that cows tend to have higher de novo and mixed fatty acids in the winter time, with more preformed fatty acids in the summer, and this is really likely due to differences in forage quality and heat stress, and how that affects intake.

00;06;05;11 - 00;06;38;14
Brad
So there's many different factors that can influence fatty acids. We have diet stage of lactation. So whether they're early lactation cows or late lactation cows, seasonality summer winter and genetics. We haven't talked about genetics, but we'll get there soon. So what is the goal of fatty acids for a Holstein herd. Well, for de novo we want to be at about 0.87g per 100g, mixed 1.4 and pre-formed 1.5.

00;06;38;16 - 00;07;09;00
Brad
So that's our goal. That's where we a good benchmark to start with. So if we think about factors that influence milk fatty acids, like I said there is nutrition and management which are concentrates dietary fat grazing. There's non-genetic factors. So stage of lactation we'll touch on those. And then genetics. Well what about nutrition management factors. Summer milk. You see increased CLA and lower saturated fatty acids.

00;07;09;00 - 00;07;42;04
Brad
The stage of lactation is very different. Usually about peak for these fatty acids tends to be about 150 days in milk, depending on what fatty acid you're looking at. If you think about it from a cow health perspective, subclinical ketosis is usually seen with higher C18 and lower C10 and C14. So subclinical ketosis we're probably seeing a lowering of the de novo fatty acids.

00;07;42;11 - 00;08;12;03
Brad
The same with subclinical mastitis. De novo fatty acids are lower when we see subclinical mastitis. So it's kind of interesting. We can think about these health issues by looking at fatty acids. So if we're not maintaining good level of de novo fatty acids in our herd, we may experience subclinical ketosis or subclinical mastitis. And then we can talk about a whole host of breeds, how some breeds are higher.

00;08;12;03 - 00;08;34;28
Brad
Jerseys are higher and some of the fatty acids Holsteins are higher, and some of the fatty acids and cross breads can be higher and some of the fatty acids. So that's what we're going to talk about at least in our first study. So we kind of did two studies here at Minnesota. Graduate student Catherine Bossley just finished her master's degree, and we did two fatty acid studies.

00;08;34;28 - 00;09;08;19
Brad
The first, we looked at fatty acids of Holstein cows compared to Holstein, might be the art in Viking red crossbred cows in commercial dairies in Minnesota. So basically, we wanted to compare the fatty acid profiles from DHEA that we get. So we collected milk samples from about a year and a half on these herds. And we use two commercial herds, one, the herd in Minnesota was about averaged about 350 cows, about 25,000 pounds of milk.

00;09;08;19 - 00;09;31;23
Brad
Herd B was closer to 800 cows and they were about the same production level, 25,000 pounds of milk or so. So we analyzed these fatty acid profiles with Minnesota DHEA, we can get this data through routine milk recording. And we wanted to look at the fatty acid profiles of these cows. We looked at first lactation cows older cows.

00;09;31;23 - 00;09;56;11
Brad
And each herd was kind of variable in their number of cows in first lactation obviously second and greater tended to have more cows than the other herds. Now, one thing that we also did with these studies was to calculate a 305 day fatty acid profile value. You know, most of the values that are coming from DHEA or your milk processors, that's on a daily basis.

00;09;56;13 - 00;10;25;19
Brad
But we wanted to see what a cow could produce in 305 days for fatty acid profiles. So we think about these two herds. Well, herd A so 350 cows had higher preformed and higher C 18 and 18. One fatty acid herd B had higher total mixed and de novo fatty acids as well as higher C 16 fatty acids.

00;10;25;19 - 00;10;50;05
Brad
So what does this mean? Well her day was feeding. Feeding well herd A was feeding a higher starch lower fiber diet increased milk production and C 18 fatty acids. But the de novo and mixed went down. So again remember we saw that if you're feeding more starch concentrate grain you see lower de novo fatty acids. Herd B we saw this.

00;10;50;07 - 00;11;18;22
Brad
It comes out in the milk. They were feeding palm oil to these cows. And that really increased C 16 in this herd. And probably really explained what we were seeing in herd B. So what about lactation number. Well first lactation cows had higher total fatty acids. They had higher pre-formed fatty acids and they had higher C18 and C18 one fatty acids.

00;11;18;24 - 00;11;50;13
Brad
So really we're seeing some physiologic changes in first lactation cow that may influence their room and function and energy partitioning. So what about breed groups. You know that was kind of one of the goal that we wanted to look at as well. So really there were really no differences between the Holstein cows and the crossbred cows for C18 or really any of the fatty acids except for one.

00;11;50;16 - 00;12;37;05
Brad
So this study found that the crossbred cows had higher de novo fatty acids, lower mixed fatty acids, and tended to be lower for C18, which is palmitic acid. So these cows may have had a small advantage in health fullness of their fatty acid composition compared to the Holstein cows, the differences were very minor, but they may indicate a role of genetics for potential niche markets with milk, fatty acid and healthier milk profiles, and the lower de novo fatty acid in the crossbred cows compared to those Holstein cows may suggest some a little bit better rumen function, a healthier rumen environment in the crossbred cows compared to the Holstein cows.

00;12;37;05 - 00;13;07;19
Brad
But differences were small in those herds. So we think about what about on a 305 day basis, we think about 305 day basis. A lot. Well, the Holsteins had higher 305 day total fatty acids, 305 day de novo mixed preform, and C16 fatty acids. However, the crossbred cows and the Holstein cows were similar for 305 day de novo and C18 and C18 one production.

00;13;07;21 - 00;13;41;18
Brad
However, the Holsteins produced more unfavorable C16, so again palm oil palmitic acid, but the differences were very small. So really the cross breads and the Holsteins were equally as good at contributing healthy fat fatty acids to the bulk tank while contributing less unfavorable fatty acids. Now, we looked at these across the lactation. If you think about it from a what what happens and how they produce fatty acids during the period or stage of lactation.

00;13;41;18 - 00;14;14;18
Brad
Basically, total fatty acids in grams per day are highest in early lactation, de novo and mixed peak around mid lactation and pre-formed are high in early lactation. So obviously the pre formed high and early lactation. That's a sign of kind of negative energy balance with those animals. And so just some changes going on in those cows. Obviously negative energy balance increases body fat mobilization.

00;14;14;21 - 00;14;45;11
Brad
And that's associated with an increase in C18. So that was kind of our first study. We didn't find we we found some small differences. But overall the groups were pretty similar. We found certain differences in herds by feeding some palm oil. And how you're feeding your cows can really change those fatty acid profiles. So the next study, we looked at our University of Minnesota herd and where we have our organic herd, about 120 cows, again pasture based herd.

00;14;45;18 - 00;15;07;02
Brad
And then we have our confinement herd which is TMR. You're around in about 180 cows. So we decided that we would compare those. If you look at the diets, obviously we're feeding more starch, more concentrate to the conventional herd than we are with the organic herd because they're going to be on pasture, at least for most of the summer.

00;15;07;05 - 00;15;39;03
Brad
So here we looked at data. It was over a four year time period. We've been collecting this data since February of 2021 with Minnesota DHEA, at least on the de novo mixed in preforms. We didn't really start collecting the C16 canteens until about 2023. We tried to do a few things differently with our herd here in Morris. We wanted to see if we could correlate fatty acid profiles with days open somatic cell count and survival to the next lactation.

00;15;39;06 - 00;16;15;08
Brad
And we'll talk about that in a little bit. So what did we find from these herds. Well organic has higher pre-formed C18 and C18 one and lower de novo and mixed fatty acids compared to the conventional herd. And we noticed that because of the grazing, it's obviously pasture is associated with decreased C16 and other de novo fatty acids, which we saw de novo lower in corn silage is associated with increased saturated fatty acids and polyunsaturated fatty acids.

00;16;15;09 - 00;16;46;12
Brad
Obviously, there was more dramatic shifts in our organic herd because of moving from TMR to pasture season. So de novo and mixed were lower in the spring and the early fall, and pre-formed was higher in the spring and the early fall. Obviously, young vegetative plants has more fatty acids in them, which increases milk preformed fatty acids. So pasture season can change these fatty acid profiles quite a bit.

00;16;46;14 - 00;17;16;28
Brad
Where we saw a higher C18 in kind of the grazing season. So that's our maybe omega three fatty acids that we see. And we're seeing that higher in in our organic cows just because they're mostly on pasture. So what about our breed groups? Again we had Holsteins. We had might be the ARD Viking Red Holstein cross breads. And then we had Normandy Jersey, Viking Red cross breads, which is something that's different than what we saw in our commercial herd studies.

00;17;16;28 - 00;17;45;12
Brad
So we have these groups of, of Normandy and Jersey and Viking Red in our herd. And what did we notice there? Well, we saw higher total de novo mixed and preformed fatty acids for the Normandy Jersey cross breads than we did for the Holstein or Pro cross breads. So we saw higher de novo fatty acids. So did these Normandy jersey crosses have a healthier rumen function.

00;17;45;12 - 00;18;10;20
Brad
Maybe. Maybe not. And the Holsteins had higher C16 was their less healthy kind of rumen environment. But really the the Holstein and the Mont period Viking red cross breads were really not much difference. Now, if we looked at the sire groupings, it's really the Normandy and the jersey that are influencing the fatty acid profile of those different cross breads.

00;18;10;20 - 00;18;35;10
Brad
We didn't see a whole lot of difference between the Holsteins and the yard crosses, maybe an indication that the de novo fatty acids were a little bit higher in might be the ARD and Viking red crosses, compared to a Holstein cow, so there may be some indication there again, that they have a much healthier rumen environment compared to a Holstein cow.

00;18;35;16 - 00;18;56;16
Brad
And these cows were fed the same or fed the same. They we did not switch rations to try and influence the fatty acids. So it's totally genetics that is causing this. Now, we did some 305 day production and wanted to correlate them with somatic cell count days open. So what did we find? Well, there was a moderate negative correlation with somatic cell count.

00;18;56;19 - 00;19;29;28
Brad
So basically we saw increased somatic cell count and decreased milk and fat synthesis. Except for the C 18. So basically somatic cell count is really influencing fatty acid profiles as well at least in our herd. So higher somatic cell count lower fatty acid profiles which is probably not a good thing. Not a good thing. Days open not much there for days open correlations of about 0.40.5 for these different fatty acid profiles in in days open.

00;19;30;00 - 00;19;55;26
Brad
So really selecting for fatty acid profile did not really hinder somatic cell count days open or survival. So it didn't negatively impact though. So that's a good thing. So in the end what did we find throughout all of these studies. Well, the crossbred cows had hired to novel fatty acids in milk. They had similar 305 day production of fatty acid profiles compared to a Holstein.

00;19;56;03 - 00;20;22;07
Brad
So we may need to think about analyzing these fatty acid profiles on a 305 day basis, at least for genetic evaluation. If we're thinking about selecting for genetics, we may have to move away from the daily. But for herd management, we want to look at that daily fatty acid profiles and higher. The novel fatty acids may indicate excellent room and health.

00;20;22;09 - 00;21;07;20
Brad
So here are some practical applications for nutrition management for dairy producers. Fatty acid testing adds a valuable management tool by monitoring these fatty acid trends, we can diagnose ration issues. So a drop in de novo fatty acid may flag suboptimal fiber levels or rumen health challenges. So if we see a drop in de novo, something's going on in the room and environment, we can fine tune fat supplementation so we can balance palm oil with other fat sources to optimize milk production and health outcomes and genetics, we can select cows with favorable fatty acids to improve long term herd efficiency and profitability.

00;21;07;20 - 00;21;37;28
Brad
So looking forward, we want processors and consumers to pay more close attention to these milk fatty acid profiles, and we'll be seeing more of this data in the future. So hopefully you've learned a little bit about fatty acid profiles today and how to manage herds. What to really look for for practical on farm metrics. You know, by looking at all of these things, nutrition, physiology, genetics, farmers can make more informed feeding decisions.

00;21;37;28 - 00;22;01;25
Brad
We can monitor herd health and really tap into some new milk markets. So with that, if you have any comments, questions, or scathing rebuttals, feel free to contact me at the Moos room. That's e m o s r o m at edu or find us on the web at University of Minnesota Livestock Extension or, Rock dairy.

00;22;01;27 - 00;22;07;15
Brad
And with that, have a great fall. Bye.