65: Beyond Fertility | Zearalenone’s Impact on Herd Health

Zeralanone is often labeled a reproductive mycotoxin, but that barely scratches the surface. This reproductive mycotoxin, is an estrogen imposter that disrupts fertility, immunity, liver function, and overall metabolic stability.

In this episode, Dr. Larry Roth explains why zearalenone is fat-soluble, how it can be stored and released during post-calving fat mobilization, and why its metabolites may be even more damaging than the parent toxin.

Learn how it contributes to cystic ovaries, early embryonic loss, cows showing heat signs while pregnant, and inconsistent reproduction, as well as why some traditional binders can make things worse.

If pregnancy rates aren’t matching expectations, this episode shows why zearalenone could be the hidden disruptor and how targeted protection like DTX helps prevent absorption before damage occurs.

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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. Hey, welcome everybody to another episode of Ruminate This with a Grand Solutions. If you've been listening along, you know that my name is Scott. And if you haven't, this is your first episode. I'll say welcome to the podcast. I'm glad you're tuning in. Make sure you hit that subscribe button. And if you find value in any of our episodes, share them with a friend and see if we can spread that value. So today we're going to be visiting with Dr. Larry Roth, Vice President of Nutrition here at Agrarian Solutions. And we're going to dive in, do a deep dive similar to like we did with the mycotoxin Don. Only today, Larry, I'm going to ask you to deep dive with me about xerolinone. Specifically, I think there's a lot of things that we know about xerolinone in the industry. I think it's it's pretty standard parlance to be having a conversation about xerolinone, and people will say things like it's the estrogen imposter or it mimics estrogen or the cows recognize it as estrogen. And inherently we know that if there's hormonal issues caused by by xyolinone, what's the first thing we go to to look at? Reproductive success. But you know, xerolinone's doing a lot more than just mimicking estrogen. So I guess where I'd like to start with you, Dr. Roth, is we know it can mimic estrogen, but what are some other things that it is doing that we don't always think about? You bet. So yeah, as you said, we think of xralinome being an estrogen imposter, getting bound at those sites, but xeralinome also interferes with general hormonal balance in the cow. And so we see hormones aren't working as they should be. The cow is a well-oiled machine when it comes to hormonal sequences, so that she's ovulated at the right time, she's ready to get pregnant at the right time, but all of that gets messed up when we've got xiralinode issues. Ziralinode also has an impact on the liver in that xiralinone and its metabolites are more like a poison to the liver, and so it interferes with the liver functioning as the body's biochemical factory. So there's really a neat story behind xralinone, not just reproduction, but it also impacts the immune system as well, and to a degree the digestive tract. Okay, so before we get into the liver and the digestive tract, quick review and take a look at the domino effect from the reproductive side, the side that everybody always thinks about. What is the domino effect there? How is it impacting reproductive success on our dairy farms? You bet. Well, first of all, again, surround functions in many ways as an estrogen imposter, takes up residence on the estrogen binding sites. And so from that, we are disrupting follicle development, follicle release, also have an impact upon the uterine environment in that the uterine wall becomes thicker and it's harder to get the embryo to implant so that it can develop. So we'll see some early embryonic death. And so little upsets here and there tend to magnify their impact. Yeah, so there's quite a synergistic effect there, or domino effect, if you would, where if we're disrupting the hormonal cues, right, that's needed for ovulation. I mean, you're talking about follicular development, you mentioned decreased follicle quality, the uterine environment and and early embryonic death. To me, that one is one that I think back through my career, Larry, spending time in the genetics world and in breeding cows. And we always seemed to this is funny because it's it's like I had a story about this here recently that played out on farm. But as an industry, we kept moving, right? Technology increased. So we went from palpating at 40 days and above to really good veterinaries with really good feel getting down to 32 days, and then ultrasound getting down to 28 days, and bloods getting, you know, a little bit further there. And we saw early embryonic death increase the more we lowered the threshold for pregnancy awareness. Well, that makes sense. The highest risk of early embryonic death happens in that what 20, 28 to 35 day window. Give or take a day or two, folks. Don't quote me on that. But early embryonic death became one of those numbers as a technician that I really, really looked at, and what can we do to improve it? Well, I was always told that it's just a byproduct. The only reason that number is getting higher is because we're preg checking sooner. Larry, palpation success rate is one of those quiet little KPIs that I think I almost call it the feel-good KPI. If we have a good herd check today, Larry, we feel good. You know, if we have 18 out of 20 pregnant, we feel good. If we have 10 out of 20 pregnant, we say, oh, it was a bad week. We'll hope for a better a better outcome next week. The palpation preg rate is also one of the things that I advise farmers to look at as an early indicator of the success of DTX, especially when there's xorolinone involved. Because we see over and over again, all of a sudden, there's more cows pregnant on vet check day. And I'm gonna say I'm gonna infer that we are helping reduce that early embryonic death loss because of xorolinone. Now, can I prove that? No, this is observational, my observational stuff that I see in the field. So, Larry, feel free to comment on that. Okay. So, yeah, the xorolinone is interfering with the corpus luteum, with progesterone production, which we think of being the hormone that promotes pregnancy. Uh, also come back to xoralinone has impacts on the immune system. We think so often xoralinone is a direct reproductive villain, but also it changes what's happening with the immune system. So if we activate the immune system, we've got to have glucose to fuel the immune system. We don't have glucose to donate carbons to rapidly growing cells, and I think that also contributes to early embryonic death. So, xeralinone, it yes, it it works in terms of blocking estrogen binding sites, but it also impacts a whole lot of other parts of the body. Yeah, very good point. So you mentioned the immune system, and I'm going to actually ask you to dive further into we're we're gonna come back to the immune system part of it, but I want you to dive further into the the liver. So, you know, you love talking about that biochemical factory, Larry. Uh, I know you do. So to walk us through what's happening to xeralinone once it gets to the liver and maybe what the liver has to deal with when it's when it's trying to treat xerolinone, I guess, or detoxify xeralinone. Without getting into all of the physiology and the enzymes and so forth working in the liver, it seems that the liver looks at xeralinone as more of a hormone than a toxin to be detoxified and broken down. So consequently, the liver is not as able to break down Dawn, is it as able to deal with LPS, the lipopolysaccharide, and also able to handle the NEPA. So we think of what's going on with the cow in the first part of her lactation. She's going through tremendous energy demands. Fat is being broken down. We have NEPAs that are being created that need to be handled by the liver, but they're not getting handled by the liver because the liver, unfortunately, is getting tied up with the rhalinone, which is being recognized as a hormone and not as the toxin that it is. So consequently, the liver isn't able to get rid of all of these oxidative species, the cannonballs that we talked about during our dawn discussion. And we see that inflammation will gradually creep up throughout the body. So we see things like mastitis, metritis that gradually start to build up. The liver and the immune system just is not able to deal with all of these metabolites that get created. So xoralinone isn't just directly impacting repro, it's impacting repro in many different ways. And some of that has to do with the liver as well as the immune system. And interestingly, we're starting to understand now that zoralinone impacts the rumen. You know, normally we didn't think of that. If we're talking about what mycotoxin affects the digestive tract, well, that would be Dawn. But it seems as high xoralinone levels slows rumen turnover, so the animal isn't able to consume as much feed, as many nutrients. We just need rumen turnover to happen so that some of these nutrients are now being presented to the small intestine instead of being broken down too far. Things like the amino acids. So we'll see variations in manure, and some of that may be due to xiral anone. So that's where we keep coming back to how these mycotoxins are also interrelated because they may be affecting the same part of the body, but coming about it different ways. So interesting that xir alone has a dramatic impact upon the rumen or fermentation that drives the animal. That that is interesting, and you know, we've talked before about the synergistic effect of multiple mycotoxins present in the TMR, and Don is almost like an indicator toxin in a way. But you know, if you look through our archive of samples, it's very common to see xorolinone and don together. Like they they like to run in the same circles. So, you know, when you think about the direct influences that Don is having on the rumen, and then the direct influences that the xerolinone is having on the liver, boy, it stands to reason when you pair these two together, and I'm gonna go back and say it, Larry, like we saw in the study we did on DTX, where we had 1.5 ppm Don and 150 ppb xerolinone. Maybe that's why we were able to see what I would call better utilization of nutrients and improved reproductive performance. Exactly. The micotoxins are creating a problem from several different angles, and now here we are with DTX able to work against both of the mycotoxins. So it it just stands to reason that if multiple mycotoxins exacerbate the problem, DTX is going to be that much more important to use in multiple mycotoxin situations. So, you know, we we talk a lot about inflammation. I want to ask you this question, Larry, and that is if I'm a herd out there today, maybe struggling with some metabolic issues. Oh, what's a good example? Maybe the percentage of cows with a BHBA over 1.2 is is starting to creep up there. Maybe we're not seeing clinical ketosis, but certainly we have signs of increased subclinical ketosis or potentially even milk fevers creeping up or metritis creeping up. And you've you know you've had the conversation with your nutritionists, we've talked about it with the vet, we've made some changes to the diet, but something still isn't quite clicking. Why should I take a look at xralinone going into my cows as a reason or as something that could be causing some of these metabolic issues? Well, just like what we've been talking about, xralinone affects the body more than just plain estrogen levels. It's affecting the energetics of the animal, how nutrients are partitioned, affecting rumen function. So many different things are coming into play. So we we think about glucose metabolism being so important. We're talking about glucose being the fuel for the immune system, donating carbons to rapidly growing cells. I like to say, no glucose, no lactose, no milk. Well, if zeral anone is impacting the immune system, we have all these oxidative cells, oxidative species bouncing around the body, and liver isn't able to clear those because the liver is all tied up with xeralinone. You can just see how so many different things come into play, all coming back to xiralinone. So we think, okay, xeralinone, that's just the repro mycotoxin. No, xralinone impacts really the entire body. So I'm glad you framed it up that way. Zeralinone is the reprotoxin. Because when you look at the I'm gonna back up, when you look at the domino effect of Don, ultimately, what is it affect repro when you start cascading? I think the the analogy we used on Don was was floating down the riverbank or floating down the river, and you end up somewhere. And where do you end up? You end up trying to get that cow pregnant when she's having to allocate nutrients to repair cells inside her body. Yeah, and then when you put xralinone, which is I think I would call it maybe a direct influencer of poor reproductive success, makes a lot of sense. But what's coming out here is that it's also maybe an indirect influencer of poor rumen health. And I think that's an important one to remind people of that if if just because we have low levels of Don doesn't mean we're having and there's alinone present, doesn't mean we're having less rumen issues per se, because the xeralinone could be helping the Don out there too. Absolutely. Yep, yep. I I think another thing we want to talk about is if xralinone is absorbed into the body, it does go through some metabolites, metabolism, excuse me, and some of these xoralinone metabolites are actually harder on the cow than xralinone itself. There was a clay product that had some research done and presented at American Dairy Science Association in 2024, and what was shown was that when this clay was fed, there were higher levels of xiralinone metabolites than when the clay was not fed, which on its face is very interesting. And so the xiralinone metabolites were a worse issue, more negatively impacting the animal when this clay was being fed. So we've got to think about how are we going to protect the cow against xiralanone, and it isn't feeding these different binders because this research study suggested that we had higher levels of these xeralinone metabolites. That's where we need to bring in DTX, keep the xeralinone from being absorbed and going through the metabolism and all of the other inflammation that we've been talking about for many different sessions. So let's just think about keep xoralinone out of the body, because it's going to impact the cow so many ways. I think so often we forget about the important roles of hormones and the endocrine system, how it affects metabolism in so many ways, be it glucose dynamics, amino acid, and protein metabolism, and the xerolinone comes in and just alters so many of these different hormones, and that's where these cows just get kind of off. We can't say, well, man, this is a real problem right here. It's more the cows are kind of blah, they're just kind of off, there isn't a snap to them. Well, that's because the hormones, the endocrine system, is off because of xeralinone. So think of xeralin as being kind of a sneaky little mycotoxin that alters so much of the cow besides just the repro system. And then we we can think of perhaps the cow as being kind of a pyramid, and at the top of the pyramid is reproduction. If the base of our pyramid is off, everything above that is going to be affected. And the reproduction, reproductive success is kind of the pinnacle indicating that the cow was working right. Yeah. So the screen impacts each layer of our pyramid, not just the reproduction. So when I talk with people in the field about the different mycotoxins that we see, you know, and I'm speaking specifically to the eastern eastern US here, and and you know, we see we see Don, and we'll have a conversation about Don, what it's doing, what it's not doing. We'll have a conversation about Femonicin, especially over the last year and a half. We occasionally have conversations about T2, HT2, and as well as Xerolinone. But Larry, Xorolinone is the only one that ever becomes controversial in the sense that when I when I say things about Xerolinone, I'll have a response like, oh, that's a myth. That's not true. And what they're referring to is Xerolinone's ability to work its way inside those fatty tissue cells and be stored in the body. And basically just lie in wait for an opportune time to wreak havoc on the liver there you go yep so is it a myth Larry or what's going on there with xirolinone and being stored in the body I think this is an important part to bring up xeralinone is fat soluble so it it can be picked up as the cow picks up body condition or even the heifer and zero anode is stored in the fat and its metabolites also and it's just laying there waiting until the fat is broken down. So the cow pressures she's in negative energy balance she's got to break down her fat reserves for energy and xiral note is now released to be floating around the body and causing its mischief. So that is where zero anone levels during the dry period or even the late lactation period are extremely critical. So the issues that we're seeing today with the newly transitioned cow, the cow that we're trying to get bred and she isn't breeding back, we need to be backing up and saying what was going on during the dry period or even during late lactation because if we had higher xiralinone levels during late lactation and dry period she was storing up fat reserves and also storing up xiralanone. Now that she's breaking down her fat reserves xralinone is being released to go throughout the body and cause all of its mischief okay well there we go we have that myth busted Larry it does happen folks and you know I so I go back to that ketosis question that I asked you or the metabolic question. And you just think and we've we've discussed this before but we think of all the things that we asked that cow to do the day she calves that liver is busier than evermation and now you're going to ask it to also detoxify the xerolinone that is being mobilized from the the energy reserves like you always say Larry what could go wrong? Absolutely you got it what could go wrong so before we wrap up Larry I just want to ask and maybe we can go back and forth on this but some things to look for within your herd to help diagnose whether or not we maybe are experiencing challenges from xorolinone. And Larry I'm gonna start I'm gonna start off by one that we don't see a lot but I have seen it in the field and we tested the forages we found high levels of xirolinone swollen mammary glands and heifers there you go yep again xirolone and metabolites interfere with mammary cell development where you were going where I thought you were going with that Scott was cystic ovaries something that's well mentioned. I I think everybody was thinking I was gonna go there but I wanted to bring that one bring that one off the bench because it's it's one of those ones you don't see a lot because we don't really feed a ton of corn silage to heifers but you you see it from time to time and and it's always chalked up as well that's weird. Yeah well right there I think if you see more weird things happening it's more of an indication that we got zero noid issues because it's such a sneaky mycotoxin cows are just kind of blonde they're not really snapping into lactation uh mammary glands aren't developing as they should or maybe they are developing too early when things are just off we don't consistently have a loose manure some days it's loose other days it's normal there's just a lot of variation all of that is pointing toward issues with with xralanone. You know we we get into a batch of cows where maybe we have a little bit higher incidence of ketosis or again cows just aren't getting bred well that backs up to pointing toward xiralone and how it was interfering with the liver and glucose metabolism so xiral alone sometimes it takes a backseat to die but zeralinone is again it's kind of that sneaky mycotoxin that affects so many different parts of the cow's body in those low little low level ways that all put together magnify the issues that they're causing to the cow yeah yep you mentioned the cystic ovaries we talked about higher than normal early embryonic death um you know some other indicators that you'll see in the field one of my favorites is if you have pregnant cows that are showing signs of being in heat. Okay so what do we do Larry we put them on the vet checklist and the vet goes and and runs their arm up or checks them again why is this cow on the vet checklist she's still pregnant well she was in a standing heat last week so that's why I put her on the list you know if you're seeing that more often than not you you may want to consider Xerolinone. Any other couple things you want to leave with the audience before we head out Larry so simple little message if things just seem out of what aren't making sense we probably need to look at Xorolinone. That's a good one and actually Larry that is a callback okay you old podcast pro and so I'm gonna send you guys back to an old saying that I have and we did an episode on this and I think it was called when two plus two equals five so that ironically enough is episode number five when two plus two equals five and you know Larry I have this theory that when two plus two no longer equals four it's probably mycotoxins and so in that episode I believe Jeff Hostetter and I discussed that and we talk about just what you said when things seem weird when things seem off we can't really put our finger on it look to mycotoxins there you go and and xoranone. So thanks for that call back Larry I appreciate it and I appreciate you once again taking time out of your day today and we'll be talking to the audience again in a couple of weeks thank you Larry right Scott thank you for listening to ruminate this with agrarian solutions look for our next episode in two weeks