Milk Components for Cheese Success-Dairy Diets, Butterfat, and Protein [Video] ▶️

00:00:04 – Thank you for joining us today for this month’s University of Wisconsin Division of Extension’s Badger Dairy Insight.

00:00:12 – This is a monthly webinar series offered on the third Tuesday of each month.

00:00:16 – Badger Dairy Insight provides the latest research, dairy based information to improve animal welfare, breeding and genetic selections,

00:00:25 – automation and modernization, and nutritional decisions for producers, dairy workers and managers, and agricultural professionals.

00:00:34 – My name is Jackie McCarville.

00:00:35 – I am the Regional Dairy Educator for Green Iowa and Lafayette counties.

00:00:41 – We hope to provide this opportunity as an informal discussion on today’s topic.

00:00:46 – As this is a webinar format, please add any questions or comments in the Q&A button at the bottom of your screen as this webinar

00:00:55 – is being recorded.

00:00:56 – You can find it on our dairy website in about one to two weeks.

00:01:00 – And we will also feature it in our monthly dairy e-newsletter.

00:01:06 – Next, we’re going to transition over to Katelyn Goldsmith and Manuel Pena.

00:01:12 – So Katelyn Goldsmith serves as Wisconsin’s

00:01:15 – but serves Wisconsin’s dairy community

00:01:18 – the statewide dairy outreach specialist with UW Madison Extension.

00:01:23 – In this role, she bridges the gap between research and practical on farm management by developing resources and programs tailored to the needs of dairy farmers and their advisors.

00:01:35 – Raised on her family’s dairy farm in Iowa, Katelyn has been involved in the dairy industry her whole life and enjoys helping farms find useful, research-backed solutions to their everyday challenges.

00:01:48 – Along with her is Manuel Pena, who was born in Colombia and earned a bachelor in animal science from the National University of Columbia.

00:01:58 – Following graduation, he came to the US for grad school.

00:02:02 – He serves as the bilingual outreach educator for the University of Wisconsin-Madison Division of Extension, working in Sheboygan, Ozaukee, Dodge, and Fond du Lac counties in Wisconsin.

00:02:15 – So with that, Katelyn and Manuel, you are free to go.

00:02:21 – Perfect.

00:02:21 – Thank you everybody.

00:02:23 – We’re excited to present today.

00:02:24 – So our portion of this presentation is kind of a complement to what John just talked about.

00:02:31 – John explained kind of why we’re in this situation right now.

00:02:35 – People are really showing a lot of interest in this ratio components in general.

00:02:41 – and especially protein has been a big topic of interest.

00:02:44 – So we’re coming from both Manuel and I are very nutrition focused.

00:02:49 – We love nutrition and management.

00:02:51 – So this presentation is really going to focus on the farm side of things, dairy diets, how can we feed for components?

00:02:59 – We’re going to talk about protein.

00:03:00 – We’re also going to touch on butterfat because it is a component of interest and then a little bit of management.

00:03:07 – So I’m going to take kind of this first

00:03:11 – portion of the presentation today.

00:03:14 – Give a little bit of a background on what we’re seeing in the industry.

00:03:18 – Some of the drivers for getting us to where we are today and then talking about supporting milk protein and how we can do that through dietary interventions.

00:03:27 – Manuel is going to talk a bit about butterfat production and then we’re going to wrap it up with some management considerations that basically benefit both protein and butterfat production.

00:03:38 – So we’ve lumped them together.

00:03:41 – So to begin with, how did we get to where we’re at?

00:03:44 – So this is a graph of Federal milk marketing order 30, which includes Wisconsin over the last about 5 to 6 years.

00:03:56 – And so I think it’s very well known, at least for our farmers out there, that we have been increasing right and butter fat and protein percentages on our farms and rather quickly.

00:04:07 – If we compare just starting in January of 2019 to January of 2026, that’s going from about a

00:04:15 – 4% to a 4.5% butterfat percentage.

00:04:20 – In 2025, the average across the entire US for butterfat was 4.3 and our protein was 3.3.

00:04:27 – So we’ve seen growth in both of these, not just butterfat, but protein has also gone up.

00:04:33 – It just hasn’t gone up as quickly as our butterfat percentage.

00:04:37 – And I’ll touch on that in a couple slides.

00:04:42 – So how did we get here?

00:04:44 – Typically I summarize it into three areas, right?

00:04:48 – Genetics, diet, and management have really been what has driven a lot of this change in our milk composition.

00:04:56 – And as a nutritionist, it does hurt a little bit to say that genetics has probably been the biggest driver.

00:05:02 – This is a really interesting graph that Council on Dairy Council

00:05:07 – dairy cattle breeding put together where they looked at the increases in fat and protein yield from our Holsteins in the last 50 years, and they broke it down by decade.

00:05:17 – But when we look at just this last column, which is the last 50 years, about 62% of the change in those component productions can be attributed to genetics.

00:05:30 – And this is a little bit of where we probably see some differences in why butterfat production has grown faster than protein.

00:05:39 – Butterfat is influenced by a couple of really key genes that when we select for them, we can see pretty significant changes in short amount of times.

00:05:50 – In comparison, protein is affected by a lot more genes and kind of in smaller ways.

00:05:56 – So we can consistently and we do consistently select for protein production.

00:06:02 – We just get a little bit smaller gains through those years compared to the butter fat production.

00:06:09 – And there is also maybe some easier ways to influence butter fat compared to protein when we talk about nutrition, but really genetics has been a big driver.

00:06:19 – So when people ask, you know, how can I really improve components?

00:06:24 – Focusing on genetics is gonna be the biggest step for you.

00:06:27 – Not to say what we talk about in the rest of this presentation isn’t incredibly important, right?

00:06:31 – Genetics opens the door.

00:06:34 – Management and diet decides how far.

00:06:37 – But if you’re looking to the future and how you wanna influence components, genetics is gonna be a big thing.

00:06:44 – But what do we do with the cows that we have right now, right?

00:06:47 – We have the genetics that we’re dealing with.

00:06:49 – How then do I essentially open that door further for them in terms of management and diet?

00:06:56 – And so I’m going to talk about protein to begin with and protein production with these animals.

00:07:03 – So in order to talk about, you know, formulating diets for protein production, we do have to understand what’s going on in that rumen and in the cow itself.

00:07:14 – So I want to take a slide or 2 to explain that.

00:07:16 – So we set the basis.

00:07:18 – And we can kind of understand then those recommendations.

00:07:21 – So the 1st big thing, right?

00:07:23 – Protein provided to the cow doesn’t magically turn into milk protein.

00:07:27 – There’s a lot going on inside of the cow.

00:07:30 – We start with crude protein.

00:07:31 – That’s just all the protein that’s in the diet.

00:07:33 – And then when it goes into the rumen, it can take really two different routes.

00:07:39 – The first route is those rumen microbes can degrade that protein.

00:07:43 – The protein that’s degraded is called rumen degradable protein.

00:07:48 – We’re not very unique in our naming, but that’s RDP if you’re familiar with the term.

00:07:54 – Those microbes can use that protein and they essentially use it to grow, thrive, reproduce, and create their own protein.

00:08:02 – We call that microbial protein.

00:08:05 – The other option is that protein goes through the rumen without being degraded and it goes to the small intestine and that’s rumen undegradable protein, so RUP.

00:08:16 – So RDP gets used by rumen microbes.

00:08:18 – They create their own protein, microbial protein, or it does not get degraded and it becomes rumen undegradable protein.

00:08:26 – These two sources are really important.

00:08:29 – Microbial protein is a huge source of protein for the cow.

00:08:33 – About 60% of the protein entering the small intestine is in the form of microbial protein.

00:08:39 – So this microbial protein, microbes don’t live forever.

00:08:43 – They die off, they go into the small intestine, or they can be attached to feed that’s going into the small intestine.

00:08:49 – Either way, it ends up there.

00:08:51 – along with that rumen undegradable protein.

00:08:54 – And I won’t get into the deep biological things that are happening, but essentially in the small intestine, both of those sources are going to get broken down into amino acids and then sent off to where they’re needed, whether that’s the tissues, mammary gland for protein production, excreted in urine or feces, or it can be recycled.

00:09:15 – back to the rumen.

00:09:16 – So when we understand kind of this process, it becomes easier to understand why we recommend certain things.

00:09:23 – So how do we support milk protein production?

00:09:26 – It’s really from a nutritional standpoint, two key areas that we can focus on.

00:09:32 – The first is enhancing that microbial protein production.

00:09:36 – So we have a lot of microbial protein that’s going into the small intestine and we’re doing it efficiently.

00:09:42 – and it’s providing adequate amounts of rumen undegradable protein and finding the balance between those two.

00:09:49 – And that’s how I’m going to kind of break up this next part is first talking about let’s enhance microbial protein and then we’ll touch on rumen undegradable protein.

00:09:59 – So like I said, microbial protein is a huge source of amino acids for the cow.

00:10:04 – And we know nutrition and management are going to influence the efficiency of this protein production.

00:10:12 – What we want to do, and probably the first key step, if you’re not already looking at this, is we need to give these microbes protein.

00:10:19 – We need to have them have protein that they can degrade, and they’re going to use that nitrogen to grow and thrive.

00:10:25 – The general recommendation on the NASEM recommendation is we want about 10% of diet dry matter to be rumen degradable protein.

00:10:34 – And in the Midwest, we usually don’t struggle to hit targets for rumen degradable protein, especially with our pretty

00:10:41 – haylage heavy diets that have quite a bit of RDP in it.

00:10:46 – Additionally, we can feed some non-protein nitrogen or NPN.

00:10:51 – If you’re unfamiliar with the term, nitrogen in general can be used to create protein, right?

00:10:57 – It’s a key part of protein.

00:10:59 – So it doesn’t necessarily always have to come in the form of a protein or an amino acid.

00:11:04 – It can be something like urea, which is a great source of nitrogen.

00:11:09 – But we do know that feeding excess NPN.

00:11:12 – It can increase nitrogen losses.

00:11:15 – It reduces feed efficiency.

00:11:16 – If we feed way too much of it, we can have some toxicity issues.

00:11:20 – So urea is

00:11:22 – Pretty common on farms.

00:11:24 – Not every farm feeds it, but it’s not uncommon to see it in a diet.

00:11:27 – We just want to make sure that we do limit urea supplementation less than 0.3 to 0.4 pounds per cow per day is kind of the safety limit.

00:11:36 – I do see quite a bit of diets that’ll go lower than that just because maybe they don’t feel like they need that much NPN in there.

00:11:44 – But it is a helpful thing to add.

00:11:46 – if you’re struggling kind of in that protein area.

00:11:51 – We also have to remember when we talk about protein production, those microbes, right?

00:11:57 – It’s a living organism.

00:11:58 – It’s a community that’s trying to thrive and survive.

00:12:01 – And this community can’t survive solely on protein.

00:12:05 – It needs all these other things to grow and live, including energy, especially when we think about it.

00:12:11 – If we give them protein, but we don’t give them enough energy, they’re going to say, I can’t do anything

00:12:16 – with this?

00:12:17 – I don’t have the energy to do anything.

00:12:19 – So we want to make sure when we’re looking at our diet formulation, yes, we need to give adequate protein, but we cannot short this rumen on energy.

00:12:28 – We need to make sure that we are promoting the growth and protein synthesis by giving enough energy, whether that’s through starch, sugars, very digestible fibers, looking at the energy content of that diet in general.

00:12:44 – And then

00:12:45 – Again, it’s a community.

00:12:46 – And if we don’t give this community a healthy place to live, they’re just not going to do the best that they can.

00:12:52 – So these microbes are really going to thrive when you have a good balance in the pH.

00:12:57 – We don’t have huge highs and low lows.

00:13:00 – We want to keep it pretty consistent.

00:13:02 – And when nutrient balances are stable.

00:13:04 – So for example, talking about energy, if we really put a lot of super digestible high moisture corn into this diet,

00:13:12 – We might see giant spikes in energy availability and then the decreases and we have nothing for a while.

00:13:18 – So we want to try to keep our nutrients balanced throughout.

00:13:22 – And that includes balancing fiber and starch levels, having some quick digesting and slower digesting starch, not cutting these animals out on fiber.

00:13:31 – Fiber is really important for that rumen mat and just in general for rumination and pH balance.

00:13:40 – So we talked about the kind of the microbe side of things and the really the big focus is give ’em the nutrients, keep the environment healthy.

00:13:48 – Now we also have the option and it should probably be used is rumen undegradable protein.

00:13:55 – So rumen undegradable protein, some people think, well, why would I want something that’s not gonna get degraded?

00:14:01 – Well, the benefit is that it goes to the small intestine and supplies some additional sources of amino acids.

00:14:08 – Then on the flip side, some people say, well, then why would I even feed rumen degradable protein if I can just supply amino acids straight to the small intestine?

00:14:17 – And really, at the end of the day, it is a balance of the two.

00:14:20 – We need a healthy rumen.

00:14:21 – We need these microbes that are able to take, frankly, pretty low quality protein at times and convert it into really high quality protein.

00:14:28 – They’re very efficient at that.

00:14:30 – And then also using this undegradable protein to optimize our balance and our efficiency and provide those

00:14:38 – amino acids that we’re really interested in.

00:14:42 – So how we can provide ruminant undegradable protein, the most common way is just via the feedstuffs that we’re feeding.

00:14:49 – In the Midwest, particularly, we have a pretty decent amount of sources we can use.

00:14:54 – A lot of expeller soybean meal, roasted soybeans, distiller grains, blood meal gets used.

00:15:01 – The big thing that people need to look at when we’re

00:15:04 – balancing these diets is the amino acid profiles between these feeds.

00:15:09 – They are all great sources of RUP.

00:15:11 – But what exactly those amino acids are can differ between the feeds.

00:15:15 – So if we’re really wanting to dial in our amino acid formulation, we need to be aware of that.

00:15:20 – And then also the digestibility

00:15:24 – of rumen undegradable protein can vary.

00:15:26 – So some of these feeds, the RUP can be very, very digestible and sometimes it’s not digestible at all.

00:15:33 – So that helps determine the quality of a feed and whether we want to include it.

00:15:38 – And then a general recommendation for RUP is usually about six to seven and a half percent of diet dry matter as RUP.

00:15:47 – If you’re someone who’s not super familiar with

00:15:50 – diet balancing.

00:15:51 – I think the fun fact that always blows people’s mind is typically we see crude proteins for dairy diets between like, I mean, 15 to 17%, but the most common is like 16%.

00:16:06 – Crude protein is pretty much just RDP plus RUP.

00:16:10 – So the recommendation of RDP is about 10%.

00:16:13 – The recommendation for RUP is about 6 to 7 and a half.

00:16:16 – You add them up, and you get 16 to about 17 and a half percent.

00:16:22 – The other big source that people talk about for RUP is rumen protected amino acids.

00:16:27 – So rumen protected amino acids commercially available in the US, methionine and lysine are the big ones, the ones that people are going to be putting into diets the most.

00:16:36 – We do have quite a bit of research out there that says rumen protected amino acids can improve milk production and component yields.

00:16:45 – And there’s some differing suggestions on how much exactly of these amino acids you should include, especially depending on how they’re protected to kind of escape the rumen.

00:16:56 – But general recommendations, methionine, we’re feeding at a little bit lower level, about 2 to 2.5% of metabolizable protein.

00:17:05 – And lysine is about 6.5 to 7% of metabolizable protein.

00:17:09 – And I know I haven’t said the word metabolizable protein yet, but that’s just the total amount of protein that’s made it to the small intestine.

00:17:17 – And typically, that’s not something you’re calculating by hand.

00:17:19 – You’re usually using a ration formulation system to calculate that.

00:17:25 – So to wrap up my protein section, basically to put it pretty simply, if we’re really focusing on how can I improve milk protein production for my animals, your big two buckets that you’re going to focus on are those things that we can do to enhance microbial protein production.

00:17:44 – So giving them the nutrients they need, keeping a healthy room and environment, and then providing adequate amounts of that room and undegradable protein to basically complement your microbial protein.

00:17:54 – And that

00:17:55 – that’s through either feed sources or using something like a rumen protected amino acid.

00:18:03 – And so with that, I’ll throw it over to Manuel, who’s going to do some discussion on butterfat.

00:18:13 – My camera.

00:18:14 – There you go.

00:18:15 – Can you hear me?

00:18:17 – Perfect.

00:18:18 – Okay.

00:18:18 – Well, thanks, Jackie, for having us.

00:18:21 – And yes, now let’s get into butter fat.

00:18:25 – You can know one before that one.

00:18:29 – Yes.

00:18:29 – So yeah, talking about fat is also very important as we saw in the first presentation.

00:18:35 – They use the main use of fat in the dairy diet is because it is a great source of energy.

00:18:41 – It contains up to 2.25 more energy per unit than carbohydrates.

00:18:48 – So that means that the cow could eat

00:18:52 – lower or smaller amounts of feed and still have the same or even more access to energy.

00:19:00 – The typical addition in the diet can be from, it is a recommendation to be from 3 to 5% of the whole of the diet in dry matter.

00:19:10 – However, of course, there are some cows that get even more fat and it is usual to have these very high producing cows getting like

00:19:21 – excessively high amounts of fat, but those additions can be, it’s not that it’s completely wrong, but they need to be added little by little.

00:19:33 – There’s not such a thing as adding 5% more of fat and having no repercussions.

00:19:38 – We can go next.

00:19:41 – So when we talk about fat, we always need to make a differentiation between unsaturated fatty acids and saturated fatty acids.

00:19:49 – So I brought these two examples we have on the left side, linoleic fatty acid, which is polyunsaturated fatty acid.

00:20:00 – What does that mean?

00:20:01 – It means that it contains one or more double bonds.

00:20:05 – As you can see in the image there, there’s like these double lines representing double bonds between carbons.

00:20:14 – So that means that it is unsaturated.

00:20:17 – You can also see that the amount of hydrogens in this polysaturated fatty acid is 32 hydrogens, and that is because those spaces that hydrogen could use now are used by the carbons.

00:20:30 – If you see in the other side on stearic fatty acid, you see to talk about the hydrogen, how it is 36 hydrogens instead of 32, but still 18 carbons.

00:20:44 – So

00:20:45 – So stearic acid is a saturated fatty acid which contains the same amount of carbons as linoleic acid.

00:20:52 – So very easy, I hope so, to understand linoleic, unsaturated fatty acids contain double bonds and they can be polysaturated when they have two or more double bonds, but they can also be called monosaturated when they only have one.

00:21:09 – And I’m making this clarification since I’m gonna be using that term later.

00:21:13 – And then in the other hand, saturated is when they have no double bonds.

00:21:17 – Those changes have an effect on melting point, for instance, and other characteristics that John was talking in the first presentation.

00:21:28 – So it’s good to know when we talk about fat, know what we talk about when we talk about saturated versus unsaturated versus saturated fatty acids.

00:21:39 – It is also very important because most of the

00:21:43 – feed that we provide to our cows are high in, if you go back, are high in polyunsaturated fatty acids.

00:21:52 – So normally the feed stuff that we provide to our cows has a higher content of these double bonds in their fatty acids.

00:22:01 – Next.

00:22:04 – So as Katelyn was saying earlier, like protein

00:22:09 – Also, the fat provided in the diet is not what goes straight to the milk fat.

00:22:15 – And to give an example of this, I have this image here where you can see this column of intake.

00:22:22 – A normal diet of a dairy cow would have a moderate amount of saturated and monosaturated fatty acids and a very high amount of unsaturated fatty acids, which are contained in

00:22:37 – corn silage, for instance.

00:22:37 – So those contain a high amount of unsaturated double bonds.

00:22:41 – Then it goes through biohydrogenation in the rumen, which is a

00:22:46 – process that happens in the rumen by rumen bacteria.

00:22:50 – And then the output, whatever leaves the rumen, is now very high amount of saturated fatty acids, similar amount of monosaturated, and of course, then a lower amount of unsaturated, which this means is that the rumen biohydrogenation is in charge of saturating those unsaturated fatty acids.

00:23:15 – A better way to see this is our next slide.

00:23:21 – So when you have in the diet your TMR has an addition of from 3% to 5% of fat and the rumen is healthy, what will happen there is that it goes through biohydrogenation.

00:23:35 – And although the unsaturated fatty acids become saturated, they make it with no problem to the mammary gland.

00:23:43 – and those get deposited in milk fat.

00:23:47 – In the other hand, if you offer higher amounts of fatty acids or your rumen is not healthy, it undergoes through an extensive biohydrogenation that could not be completed because the rumen microbes are overwhelmed by either the amount of fat or

00:24:13 – the changes in pH, and then it generates some of the byproducts of biohydrogenation that does not complete the transformation to saturate it, and then creates these byproducts or byproducts of biohydrogenation, which there is specifically one that is the trans-12 cis-10 fatty acid, which causes milk fat depression.

00:24:42 – What that means is that that specific molecule that is produced in biohydrogenation can go to the mammary gland and inhibits the deposition of fat in milk.

00:24:58 – There is this way to see it also if we think of the rumen as this rectangle

00:25:04 – and then we feed unsaturated fatty acid biohydrogenation.

00:25:09 – What biohydrogenation does is to delete one by one those double bonds.

00:25:14 – So let’s say, let’s talk about the linoleic fatty acid.

00:25:19 – It goes through biohydrogenation, becomes monosaturated fatty acid, and then saturated as saturated fatty acid.

00:25:26 – If there’s, again, like

00:25:29 – if the pH fluctuates too much or there is a lot of fat that overwhelms the microbes, then it creates dose of products of bioheterogenation.

00:25:38 – And one of them specifically can lead to milk fat depression because of the inhibition of fat synthesis, milk fat synthesis in the mammary gland.

00:25:51 – Next.

00:25:53 – Oh, so yes, if you have any issues

00:25:57 – with the amount of fat that your cows are producing, one thing you can do is go check the amount of fat you’re feeding.

00:26:06 – Because again, if you are feeding way too much, then probably you are stressing these microbes a lot.

00:26:12 – But it’s not only the amount of fat that you’re feeding, but also the profile of fat that you are feeding.

00:26:19 – So to prove this point or to give an example of this point, I have the two profiles of

00:26:27 – both conventional soybeans or high oleic soybeans.

00:26:30 – They both provide a certain amount of fat, but the fat they provide is completely different.

00:26:36 – On the left side, in the conventional soybean, there is a high amount of linoleic fatty acid, that is a polysaturated fatty acid, which has two double bonds.

00:26:46 – Thus, the process of biohydrogenation is going to take longer to get concluded.