73: Heat Stress and Inflammation in Dairy Cows

Summer heat stress in dairy cattle is about far more than fans and sprinklers. In this episode of Ruminate This, Scott Zehr and Dr. Larry Roth discuss the hidden biological effects of heat stress in dairy cows, including inflammation, leaky gut, oxidative stress, altered blood flow, and immune disruption. They also explain why heat stress should be viewed as an inflammation challenge rather than simply a temperature problem.

The episode also explores how DTX™ with Livox uses probiotic technology and plant actives like curcumin, naringen, and carnosic acid to support dairy cows during periods of heat stress. Learn how internal biological support may help cows better withstand the stacked environmental insults of summer while supporting health, performance, and resilience. 

🎧 Listen now on Apple Podcasts, Spotify or your favorite podcast platform 

💬 Have thoughts or a story to share? Email podcast@agrsol.com.

🔗 Stay informed: Get expert livestock nutrition insights, cutting-edge research, and updates on future episodes by subscribing here: agrariansolutions.com/podcast

Social Links:

YouTube:  https://www.youtube.com/@RuminateThis
YouTube Page:  https://www.youtube.com/@agrariansolutions5557
LinkedIn:  https://www.linkedin.com/company/agrarian-solutions/
Facebook Page: https://www.facebook.com/AgrarianSolutions
Instagram Page:  https://www.instagram.com/agrariansolutions/
Website: https://agrariansolutions.com/

Transcript

0:01

Hello everyone, welcome to Ruminate This with Agrarian Solutions. Join us as we explore ruminant nutrition and the impact of mycotoxins. Here we challenge your curiosity and explore new industry insights and research to optimize your herd's health and performance. Larry, thanks for jumping back in the hot seat with me. Hey. That was a good one, Scott, for our topic today. Hi, hey, no pun intended, but we are going to be talking about heat stress. Just kidding. It is heat stress topic, but Larry, we talked about challenges in our last episode that arise from temperatures and humidity being too warm for cattle. And there's a multiplying effect that takes place uh on the cow when she experiences all these environmental challenges that are in some ways exacerbated by the temperatures outside. But today I want to talk about something a little different angle on this. Number one, I guess a message that I would have, and Larry, chime in on this if you want a message that I would have to the producers and the nutritionists and the veterinaries, the consultants out there. We have to continue the conversation always about what a good heat abatement strategy looks like, right? And we need airflow, we need, I think there's many parts of the country, even in the northeast here, adequate sprinkling and evaporative cooling. That stuff is important. And I'm not in any way trying to minimize the importance of heat abatement. And would you agree, Larry? Absolutely. Heat abatement, and maybe we can call that external is important. It's important to get the ventilation to help move air. It's important to help cool the cows through sprinklers. All of that, maybe we call it external, is extremely important. We're not trying to negate that. Exactly. Where I'd like to dive into a conversation with you today, Larry, is hey, I'll be frank with you, Larry, and the audience. We're not a heat abatement company. If you want to email the show podcast at agr.com, I will put you in touch with people that I know that are heat abatement experts. But it's the advice isn't going to come from me. I, you know, we specialize in biological support. So Larry, I want to I wanna so I want to talk about biological support for the cow. But before I dive into my first question for you today, Larry, when it gets hot outside, what's the first thing you want to do? When it's hot outside, first thing I want to do, turn on the AC. Okay. And then you want to turn on the AC inside, but you're outside working in the sun, you don't have access to air conditioner in your tractor or your car. What's the first thing you grab to drink? First thing you're gonna grab to drink, hopefully, is some type of electrolyte solution, not to name anything products by name, but something that is going to provide some electrolytes, maybe a little bit of sugar. We can get into some of that, but yeah, something that is going to help me from an internal support standpoint. Hydration, how's that? Yeah, and that is built into us. We, as humans, we totally understand, I think at this point in our world, the importance of hydration. And true hydration isn't just drinking water, our cells need support to get that water into the actual cells, right? And that's where we talk about electrolytes and sodium being a carrier and so on and so on. Why is that overlooked in dairies? Wow, that's a great question. Again, I think part of it is going to come back to our human nature when we think about getting heat stressed ourselves, AC, jumping in the lake, the fan, those types of things. And so we instantly go that to that avenue when our animals get heat stressed. Yeah. Yeah, I think that's fair. And so I guess my first question for you, and now that we've framed up the entire conversation for the day, a little bit of piggybacking on what we talked about in our previous episode. So we know that these elevated temperatures, but dare I say the words heat stress, it's not just the elevated temperatures and humidity that is causing a direct problem for our cattle, but it's also exposing, I'm gonna call them weaknesses or other insults the cow is facing within her body. So, what's actually happening inside the cow that we're not always accounting for? Okay, great question. I think the first thing that we need to consider is our animals are going to a higher respiration rate. Okay, that's how cows cool themselves through their lungs. So, with that increased respiration rate, we are losing moisture through the air that is exhaled. So we're going to be shorting cells on water because we're losing it. So we need to make sure that the animal has plenty of access to water. We are also changing blood pH because we're getting rid of all this carbon dioxide, which is changing blood pH. So now we start thinking about the electrolytes. Then we start thinking about blood flow. The animal, number one, first increases respiration rate, number two, changes blood flow so that the blood flow is going more to the extremities, the skin, the legs, the ears, and consequently, we don't have as much blood flow to the digestive tract where we're going to absorb nutrients and losing water, changing blood flow. We run the risk of intestinal lining cells, again, as you know, I like to call that the castle wall, now becomes dehydrated, the cells shrink. What used to be tight junctions between cells is no longer tight. So it's all one great big system, Scott. And so often when we think of why animals or people die of heat stress, I think it's two things it's blood pH and it's septicemia, bacteria getting in the blood. So we need to provide some electrolyte support from a pH standpoint. We need to provide water to help cells get hydrated, osmolites to help draw water into the cells, and then immune support for when leaky gut does occur. Because now we've put an extra load on the immune system. Now the liver has to detoxify and clean things out of the system that it didn't before. So this is where the internal aspects come into play. Again, defend the castle wall, protect the liver so the liver can function the way that it's supposed to. Yeah, you talk about the castle wall a lot, right? And we're talking about the tight junctions there in the small intestine. And I think one of the reasons I love your castle wall analogy, and I'm gonna go, I know you always talk about the medieval castle, but when we're on a farm, and I think going back to the start of this episode, we think of heat abatement and we immediately go to air conditioning, fans, sprinklers, right? Things that we can see, we can touch. Some of these farms have fences around pastures or gates around pens. That's a castle wall. What happens when it breaks open? We have chaos. Yep, and it's the same thing in that small intestine is to where when we have a breakdown in these tight junctions, there's chaos. And you just explained some of it, but walk us through a little more of what that actually means and why it matters more than people think, because we can't see it, we can't see it happening in live time like when the cows run through the fence. Yeah. So let's talk about losing the tight junctions. We think of the cells as being the castle wall, the blocks of stone that's in the castle wall. Well, those blocks are held together with mortar, and that's what the tight junctions are, fills the gaps in between. So we have to remember that these tight junctions are made out of certain proteins, and we need to protect those proteins. That brings us to one of the key components of DTX, and that is the curcumin. Curcumin helps to repair these tight junctions, helps to hold the cells together. So we always need to be thinking: how can I get curcumin into our animals, not just things like betane, the with the osmolite to keep water in the cells, but to defend the tight junctions, and that's where curcumin comes into play. And to follow up on that, it's not just getting curcumin into the cells. And we may see curcumin represented on labels as turmeric, but here at Gray and Solutions is it's not just the feed ingredient, it's the actual plant active entering into the phytogenic world where we're identifying the specific molecule, the specific compound that is needed in the animal. Well, curcum is a very large molecule, consequently, poor bioavailability. And folks that we work with have identified, Scott, that we need narrogen. Naringen comes from grapefruit peels, and narringin helps to improve the absorption of curcumin. Fantastic. We're putting curcumin into the animal, or like myself, I even take curcumin myself. If I'm not taking narringin with it to serve as uh increasing the absorption of curcumin, I'm just wasting my money. So curcumin has an antioxidant role, it has a tight junction protein rebuilding role, and then we need naring to increase the bioavailability of the curcum. So, what's that got to do with anything? Again, it comes back to helping the animal respond to heat stress internally. And yeah, intestinal cells are dehydrated, they shrink, we lose our tight junctions. Then we have bad stuff getting into the body, we need more antioxidant support. No, let's defend right there at the castle wall, or go out and use your analogy, repair the fence so that cattle stay in the pasture where they're supposed to be and don't cause chaos by getting out. So it's a really neat system where we look at external heat abatement and then, shall we say, internal biological support. Defend the castle wall, protect the liver so that the liver can better function the way that it's supposed to. So I'm gonna piggyback off what you just said as far as the liver. And in case the listeners wondering right now, yes, we are talking about supporting the animal biologically, yes, heat can cause inflammation inside that cow, an immune response. We have to we have things that we're talking about, we have to repair like tight junctions and all this stuff. But the liver, as Larry said earlier in the episode, is now taking on more of a role. And if you haven't guessed by the title of the episode, I'm introducing the idea today, Larry, that if we're able to support that cow biologically, and I'm not introducing it like nobody's ever talked about this, don't take it that way. But if we're supporting that cow biologically with the tools that we have available to us here, and that nutritionists across the country have available to them in their feed mills, DTX, we're actually bringing more to the table than just research-backed mycotoxin mitigation. Because, as you already mentioned, there's curcumin and narrogine in there to help with the tight junctions. But now, Larry, I'm gonna ask you to talk about carnesic acid. Because I think out of the plant actives that we have in the DTX today, the carniusic acid one to me is very intriguing. Well, you talk a lot about the liver being a biochemical factory of this cow, and when heat stress and mycotoxins are hitting at the same time, it makes me ask what kind of load does that put on the liver? And where do things start breaking down? And then lastly, how does carnesic acid from rosemary come into play? Fantastic. So let's think of heat stress as really being an inflammation story, yeah. And we're trying to stop inflammation right there at the castle wall. Things get through, and now we're thinking about rosemary and the plant active, it supplies carnic acid as being fantastic antioxidant support. So the liver processes nutrients, the liver cleans out different toxins, very important organ, the body's biochemical factory. So, what's carniusic acid got to do with it? Very strong antioxidant. Think of these metabolites that are created in metabolism, in pathogen attack, mycotoxin absorption. We call them reactive oxidative species, ROS. Okay. Analogy time, Scott. I think of these reactive oxidative species as being like a cannonball that bounces around in the body, causing damage to membranes and creating more of these electrically charged cannonballs to cause damage. Scott, we got to stop these cannonballs. And that's where the antioxidants come into play. They stop the cannonballs from bouncing around the body, damaging membranes, and provide that internal support. So I realize, Scott, that we're talking about heat stress here today, but I want to talk about a study that shows the importance of carnic acid for protecting liver health. This is research that was actually conducted at South Dakota State University. They supplemented carnesic acid for day one and three. First, the day that the cow calved, second day and third day, and then stopped. What they saw was that supplying the carnesic acid for those first three days reduced the inflammation load on the cow. That's good. But more importantly, set the cow up for increased milk production as far as 21 days later. So showing the importance of antioxidant support where the stressor in this case was freshening. As God, in other settings, we've talked about how the calving process and the recovery process puts antioxidant stress onto the cow. So we won't go down that route. But I'm just saying that's a model that tells us carnic acid provides antioxidant support. So let's look at putting rosemary and carnic acid to work for us, protecting our cows from the oxidative stress that comes from heat stress. So it's neat how all of this comes together. Yeah, Scott, I'm not saying that external heat abatement isn't important. By all means, ventilation, cooling, all of that is extremely important. Osmolite support is important, but let's defend the castle wall, let's maintain the tight junctions, let's provide antioxidative or antioxidant support to defend the liver. It all comes together. So, Scott, we're offering the curcumin, the narogen, rosemary, carnesic acid in the DTX. So you made a reference earlier to DTX being a top rate mycotoxin mitigation product. I think we're also doing some things to help defend the castle wall and help defend the liver that comes into play. Let me make another comment about heat stress. So often when the environment is hot, the feed gets hot because the weather is warmer, the feed is warmer, wild yeast can take off and grow in the feed. That messes up ruminal fermentation, scientific term for you. That reduces the nutrients that are available to the cow because of impaired rumen fermentation, and the cow is not consuming as much feed because of the things that are growing in the feed, plus the heat. Because we all tend to eat less when it's hot at 4th of July than what we do at Thanksgiving, and the cow is no different. So, Scott, it's an incredible biological system, the cow, and we have to think about all of the different ways that heat stress impacts her, impacts her body externally, impacts the feed, impacts her digestive tract, heat stress, even impacts the liver. So let's put together a well-rounded coordinated defense program to protect the cows during the heat stress. I would agree, and I'm just gonna say so the way DTX is designed and formulated now, and I don't want to confuse anybody that we're trying to be something we're not, because up until last year, DTX was our cell wall deficient probiotic that is there to combat the negative effects of mycotoxins. And again, Larry, I'm gonna come back to it's really the most vetted mycotoxin mitigation product on the market, one of the largest studies ever done, if not the largest study ever done in the realm of mitigating mycotoxins. You guys reformulated, didn't change anything with the probiotic. We added in the next frontier of biological support from the terms of tight junction support, liver antioxidant support. And Larry, I'm just gonna say from my perspective as a field consultant and as somebody that's been in dairy my whole life and on this side professionally now for close to 13 years, I don't know if DTX would be the first product I would run to as a heat stress support product, and I want to be clear on that. But I would say from if I'm looking to support my cow biologically, and what is that cow? You already said she has a biological system, and within her is a bunch more biological systems. Here is something that can support those biological systems, yeah. And I think that to me makes a lot of sense just as a somebody that knows cows. I'm gonna agree with what you said, and so I'm not gonna classify DTX and its components as heat stress abatement. How about more dealing with inflammation? Yeah, and in this situation, we're talking about inflammation due to heat stress. As I said before, do all you can from a ventilation standpoint, do all you can from uh sprinkler cooling standpoint, do all you can from a beta electrolyte standpoint, do those absolutely. But now to provide some inflammation support, consider DTX and What it can do from a probiotic standpoint to help defend the castle wall against mycotoxins, and then the plant activities, the phytogenic components that help to maintain gut integrity, maintain the tight junctions, and then provide antioxidant support. So it all comes together. There aren't any cellar bullets. Scott, there's no one product that's going to take care of everything, but let's start looking at putting together complementary components to make a whole program. Exactly. And the one thing I want to add in here is as I mentioned in the last episode, I mean, this issue that we deal with in every part of the country, which is heat stress, it's something that robs the U.S. dairymen of over a billion dollars a year annually in production losses. But in my own field experience, Larry, over the last couple of years, and especially last year, I remember having conversations with nutritionists last year in July in New York, hot, humid. Hey, I haven't heard anything from you, kind of worried. How are your cows doing? Over and over. This is the best summer our cows have ever had. We still had mycotoxins. It's not like all of a sudden mycotoxins took the summer off, so that was one less inflammation point. They were still there, but those cows were experiencing the benefits of DTX and of the Livox, which is the plant actives in DTX. And I Larry, I that's not research-proven what I just said, but I don't think it's a coincidence that last year during what was in the northeast and many places a drought, record heat, record lack of rain, so not a lot of cooling at night. We saw less herds that we work with losing those great big swings of milk. And if you're a dairyman or a nutritionist or a veterinary and you're thinking of herds you're working with, and you guys are seeing some of those swings in the heat can be anywhere from five pounds of milk if you're lucky. But Larry, I've also heard of guys losing as many as 10 to 15 pounds of milk. Yeah, I don't care how many cows you milk, 10 to 15 pounds is a lot. Five is too many. Maybe you don't have a big mycotoxin load in the TMR. And by big, I'm gonna say you look at it and you say that's relatively clean, not much shows up in the assay. You know what? DTX is still gonna be there to take care of whatever is there, and also that support from the biologic side, from the phytogenic side, the plant actives. So I would really just kind of think about as we wrap up, Larry, how if I'm in the business of getting cows pregnant, keeping them pregnant, and making milk in today's U.S. dairy economy, I'm thinking of how do I not survive the summertime? I'm thinking about how do I maximize my opportunity in the summertime heat. And perhaps one of those ways is helping that cow biologically. How about we think of DDX from this standpoint? It's a way to biologically reallocate nutrients. Instead of nutrients being allocated to dealing with the consequences of heat stress. Nobody said consequences, repairing the gut, providing antioxidant support, dealing with liver issues. We think of DTX and its phytogenic component as a way to biologically help defend and protect the cow in our conversation today, so that nutrients are reallocated to more profitable purposes. In some situations, it might be growth, other situations, milk production, and then finally reproduction. So let's think of it not as a heat abatement product, but as a biological nutrient reallocator, in this case, helping cows deal with the inflammatory consequences of heat stress. Larry, my last question for you was going to be this, which was why do you think internal support, such as gut and liver resilience, is still one of the most overlooked pieces of heat stress management? And I guess feel free to comment on that. But what I would say is if you're a person that is overlooked biological support in the past, rewind this episode about 25 seconds and listen to what Larry just talked about. Because if there's been one thing consistent that we've talked about on Ruminate this in the 70 plus episodes that we've been here, it is that TMR is that nutrient pie for that cow every time you put it down in front of her. And she has a hierarchy of needs, biologically speaking, of how she's going to allocate those nutrients. Number one, the immune system. We got to stay alive. However, many nutrients we divert to the immune system is that few, that many fewer nutrients we get to do the things that Larry just talked about, which is milk in Repro. So, yeah, Larry, final words. Scott, we're dealing with a complex biological system, the cow, who's made up of complex biological systems. Let's use the DTX and its probiotic component and its phytogenic plant active components to help relieve some of the inflammatory consequences of heat stress. Put together a whole program, keep the cow cool, and then bring us along to help with the inflammatory consequences. If we're supporting the cow with heat abatement strategies on the outside, it's awfully complimentary, not ironically, to support that cow with biological approach on the inside. Love, love the takeaway, Larry. I appreciate you coming on here today because it's and it's a timely conversation. We're at the middle to the end of May, and the temperatures are going to start heating up in certain parts of the country soon. They've already started heating up in other parts of the country. Time to act. Very cool. Larry, I appreciate you coming on today, and we'll be talking again on other topics uh in the future. So thank you. Have a great day. All right, thank you. Bye. Thank you for listening to Ruminate This with Agrarian Solutions. Look for our next episode in two weeks.