A dairy producer asked a simple question: “Every time I feed a clay binder, my cows’ manure firms up. If it isn’t binding the mycotoxins, why does that happen?”
In this Letters from the Field episode, Scott Zehr and Dr. Larry Roth explore the science behind clay-based mycotoxin binders, manure consistency, gut health, and nutrient bioavailability. They explain why firmer manure doesn’t always mean the underlying mycotoxin challenge has been addressed, review the research on how clay binders perform against common mycotoxins like DON (vomitoxin), aflatoxin, fumonisin, and zearalenone, and discuss an alternative strategy focused on protecting intestinal integrity rather than simply binding toxins.
If you’re looking to better understand what manure consistency is really telling you, this episode delivers practical, research-backed information for managing mycotoxin challenges.
🎧 Listen now to set your herd up for lifelong success!
Scott Zehr: Hey, welcome everybody back to another episode of Ruminate This with Agrarian Solutions. I am your host Scott Zehr. And today Dr. Roth is joining me and Larry, we’re gonna talk about something that is near and dear to your heart. Welcome back to Ruminate This.
Dr. Larry Roth: All right.
Scott Zehr: All right. Well, you say that now. Uh, so Larry, you know, you and I have talked about mycotoxin mitigation a couple of different times on this platform. We have talked about binders at least once on this platform. One of the cool things about working in the field is that we come across different situations, different conversations that, that make us ask ourselves a question.
And, one of those such conversations you recently had at a dairy. And so I thought it was, it was a good idea to bring that in as kind of a Letters from the Field episode. Essentially the question is, Larry, why when we put in a, say a clay-type binder for mycotoxin mitigation, do we see changes like the manure stiffening up?
Which, you know, if we have high DON, we could have rumen disruption, rumen inefficiencies, all the things we’ve talked about before. And one of the symptoms of DON is that sporadic loose manure. So Larry, I’m a dairy farmer. I throw in some binder. The manure stiffens up. Problem solved, right?
Dr. Larry Roth: Not exactly. So let’s work with the i- idea that we’re putting in some hydrated sodium calcium aluminosilicate. That’s a l- long series of words, but it, it, it’s kind of a refined bentonite. Let’s, let- let’s go with that, okay? So why would we see things getting better? I’m gonna term things getting better from two standpoints.
One, what you were just referring to, the manure is a little bit stiffer. Well, these aluminosilicates, will bind water. Sometimes we use them in different situations to soak up water, s- soak up oil on the shop floor. That may be a little bit of what’s happening. So we’re absorbing some of the moisture that’s in the large intestine.
Manure is a little bit drier. It seems like it is firming up. We could also go with the example of, um, seems to be working that maybe milk production comes up a little bit, maybe repro improves a little bit. Probably not a whole lot. But let’s just say for the sake of discussion, the mycotoxins that we were concerned about were zearalenone and fumonisin.
Well, one of my favorite research studies is Cajal et al from 2022, the meta analysis of over 60 different peer-reviewed articles looking at the ability of different feed ingredients to bind or tie up different, uh, mycotoxins. And that would suggest that the aluminosilicates would bind 52% of the fumonisin and 52% of zearalenone.
So if we have low to medium mycotoxin levels, we’re, we’re gonna tie up some mycotoxin, yeah, we are. But if we have high levels of mycotoxins, I would contend that the aluminosilicates and some of these other, quote-unquote, “binders” are gonna be overwhelmed by the amount of mycotoxin that is in the diet. But at the same time, Scott, you’ve gotta come back and realize that these, quote-unquote, “binders” are also tying up some of our nutrients.
So principally minerals, amino acids, and some of the vitamins that, that support the immune system. So when we say, “Oh, I put in a, quote-unquote, binder, and cows seem to be doing better,” what do we mean? Do we mean that the manure is firmer? Are we seeing improvements from a repro or production standpoint?
I could see at low mycotoxin levels, you might see some benefits. But very easily the binder could be overwhelmed, and you have to think long-term, are we, uh, costing ourselves because we’ve reduced nutrient bioavailability? So a lot there to unpack
Scott Zehr: There is. I think first, when I, I think through what you just said, I, I wanna capture something you said because we can go to the, the Cajal et al research on the binding efficiency of the mycotoxins.
But I wanna come back to, and I’ll do a callback for one of our previous episodes called “Where Did the Protein Go?” And I believe that was episode 76. And we talked about why has, why haven’t we consistently been able to get protein up higher than what it is? And some of that comes back to this question I have from you.
So when, when you look at the, the research they’ve done with binders on, on amino acids, and I think this is not talked about nearly enough. Larry, I’m gonna s- I’m gonna say that you and I talk about it a lot. We talk about it a lot internally, but you don’t hear it talked about in the popular, mainstream dairy press.
Scott Zehr: I’m just gonna run through the list of results here. So take bentonite…
Dr. Larry Roth: Okay.
Scott Zehr: Tying up, 28.3% of lysine. Montmorillonite tying up 47% of lysine. Yeast cell wall fractions, 38% of lysine. And there’s other amino acids that’s mentioned here as well, and the range is from 28% to as much as 58% on certain amino acids. What is that, what is the net result of that happening?
Dr. Larry Roth: Okay. Right. So we are tying up amino acids. We don’t have amino acids to go into making, uh, milk protein, which is where you started your question at. We don’t have amino acids to support immune function, rebuild tissues. And you really need all of these amino acids in the right ratios to make full use, be it, um… or to get the most efficiency. Be it for milk protein, rebuilding the body, repro, immune function, what have you.
So if we are reducing lysine availability, we’re not able to make the complete proteins. We lose the protein or amino acid efficiency. Yeah, we’ve got plenty of the other amino acids, but now we’re short on lysine, so, um, that’s our limiting factor. And, milk protein isn’t gonna be what it could be, nor are we going to have the health and repro that we would want to see.
So feeding a feed ingredient that ties up lysine is going to negatively impact protein efficiency.
Scott Zehr: Okay
Dr. Larry Roth: As well as efficiency of other nutrients
Scott Zehr: Okay, so talk about methionine in that same way.
Dr. Larry Roth: Sa- same…
Scott Zehr: Cause we’re talking 50%, 51% depending on the clay, 40% for mont- mornite, 47% for yeast cell wall.
Dr. Larry Roth: Yep, same thing. Now we’re tying up some of our methionine that we need in certain ratios to make the complete proteins, and all of a sudden we’re missing some of our building blocks. So poorer protein efficiency, poorer amino acid efficiency because we don’t have all of the nutrients that we need in the right ratios.
Scott Zehr: Maybe I should apologize to the listener just a little bit, Larry, because I kinda took us down a rabbit hole. Um, you know, the, the original question was why the, why does that manure stiffen up, right? And here we are talking about amino acids, but I, I think it’s relevant. Because I think we…
Dr. Larry Roth: Absolutely.
Scott Zehr: And I’m gonna go back to a comment I’ve made before, is, i- i- I think a lot of these products were developed for combating a specific issue a number of years ago called aflatoxin.
Dr. Larry Roth: Yep.
Scott Zehr: Um, and now we’re still broadly using them for other mycotoxin related mitigation. So we talked about this, these binders getting into the rumen. You know, they’re absorbing moisture. Do you think just the moisture absorbency is what gives the appearance of the drier manure? Is that what you’re kinda getting at?
Dr. Larry Roth: I think so. I think so. Now we may be tying up some of the other mycotoxins, and in my earlier example, Scott, I used fumonisin and zearalenone because the alumino silicates, um, tie up more fumonisin and zearalenone than they do DON or ochrat or T2. But the aluminosilicates are very effective at binding aflatoxin.
Aflatoxin is a carcinogen, negatively impacts the liver. So yeah, if we… But, but again, when do we see aflatoxin? Generally during a drought. And we just don’t see as much aflatoxin anymore as compared to, say, 25 or more years ago. We’ve made tremendous strides in agronomic practices, also in corn genetics, which is more resistant to drought or drought tolerant. And so we just don’t see aflatoxin like what we used to.
Scott Zehr: So, going back to this, this whole firm manure thing. You know, Larry, we, we have a product called DTX that we have research on. And,
Dr. Larry Roth: Mm-hmm.
Scott Zehr: You know, we have… I, I’m just gonna speak from my own personal experience in the field over the last five years. So many times I see farms, they’ll put their, their herd on DTX, manure changes within three to five days… Stiffens up.
Dr. Larry Roth: Mm-hmm. Yep. Yep
Scott Zehr: hear the same thing about the clays. So if our objective is to stiffen up the manure, we can do that, but walk us through the differences between one product is doing, which you just explained, right? We’re absorbing some moisture where, where you have drier manure. Well, we’re not relying on binders with DTX. We have- we’re a probiotic. So what’s causing the manure to stiffen up there?
Dr. Larry Roth: Okay. We’re protecting the animal against the negative impacts of DON for destroying gut integrity, so you don’t have the leaky gut where we have nutrients coming back into the digestive tract and being consumed by undesirable bacteria in the small and large intestine. So let’s absorb nutrients where they’re supposed to be absorbed, the small intestine, and don’t have them coming back into the body through leaky gut.
So protect gut integrity, help nutrients to be absorbed, stay absorbed, and not end up flowing back into the digestive tract. That’s how we’re improving manure consistency with DTX.
Scott Zehr: Okay. So w- w- we’ll talk about that manure just a little bit more. You know, we’ve, we’ve all looked behind the cow. Um, granted, you’ve probably looked at, at more manure in your life than I have. Uh, but, um, you know, it’s, it’s, it’s one of the quickest indicators we have. But…
Dr. Larry Roth: Yep.
Scott Zehr: the biggest misconception producers have about what, about manure when evaluating, say, the addition of feed additives?
Dr. Larry Roth: Okay. What are some of the biggest misconceptions about, shall we say, manure consistency when it comes to some of these mycotoxin protection-type products? Well, we could still have challenges induced by DON changing the balance of bacteria in the rumen. We could still have leaky gut. But now we’ve got the bentonite or aluminosilicate in the hindgut to bind some of the moisture and firm it up.
So I think the biggest misconception we would have with aluminosilicates is they’re putting a Band-Aid on the problem, but not solving the problem back in the rumen and the small intestine. It’s all about gut integrity and having the right balance of bacteria in both the rumen and the small and large intestine.
If we lose control of microbial balance in the small intestine, and especially in the large intestine, we can get all kinds of fecal abnormalities.
Scott Zehr: So, Larry, let’s pretend I’m a producer for a minute. We have, uh, some cows that are a little off feed. We have some loose manure going around. The nutritionist puts in a product.
Um, you know, I’d say I, I, I put a binder and we’re good. You know? Take care of that. How, how can I as a producer know if the ingredients we’re talking about here today, bentonite, hydrosodium sodium aluminosilicate, Montmorillonite, yeast cell wall fractures, how do we know if those are the ingredients in the product or not? How can we find that out?
Dr. Larry Roth: How do we know if… Okay. We should be able to look at our feed.
Scott Zehr: Yeah
Dr. Larry Roth: We should be able to ask our nutritionist, “What are you putting into the diet for mycotoxin protection?”
Scott Zehr: Mm-hmm. Okay. ‘Cause it, you know, and I, I bring that up because, sometimes I think probably most producers are familiar with bentonite. That’s a very common, we throw in bentonite. But, all my years of, of being on the dairy, we fed binders back then. And, if people have been listening long enough, they’ve probably heard my, my binder story and, and how I swore I’d never work in the mycotoxin mitigation space because it’s all a joke.
Um, but, you know, then all of a sudden I find Agrarian. So that being said, though, uh, I just never remember hearing, you know, well, I, I threw in some hydrosodium alumos- aluminosilicate, right? We hear terms like bentonite. But there’s product names out there, and I think for the most part…
Dr. Larry Roth: Yeah
Scott Zehr: uh, Larry, and I’m, I don’t wanna step on anybody’s toes too hard, but for the most part, anything that’s out there is, generally speaking, a combination of a clay or a yeast cell wall or some of both. Maybe some enzymes.
Dr. Larry Roth: Yes. Perhaps.
Scott Zehr: Yeah. I think I’d really challenge the producer that you visited with is, is to, you know, okay, the manure stiffened up. Great. Larry, was that his only objective with mitigating mycotoxins?
Dr. Larry Roth: I think that his objective is to create healthier, more productive cows. Protecting against mycotoxins sounds well, but at the end of the day, the objective is to make money on the dairy. And the way that we make money is cows making milk and get pregnant and stay pregnant. So okay, fantastic. We saw a very quick result, manure firmed up. What are we seeing for production and repro?
Scott Zehr: Just out of curiosity, Larry, this one might get me in trouble. Are there many research studies out there on mycotoxin mitigation products that show an ROI?
Dr. Larry Roth: Very limited in terms of research studies where feed ingredients used for mycotoxin protection, note how I said all that, have shown a return on investment. They may show some returns at low levels of mycotoxins, ’cause again, Cajal et al says we’re going to tie up some of the mycotoxin. But it’s very easy for the mycotoxin contamination to overwhelm the supposed mycotoxin mitigation products. So, very limited, and the studies that are out there are with very limited numbers of cows.
Scott Zehr: Yeah I’m gonna come back to this again, right? So it’s a term that I think we sometimes hear overused a little bit, but let’s look at the data, right? And I think of DTX, and I’m getting a little promotional here, but this, this question about binders comes up a lot. And Larry, it… You know my take on this and how I think that, I think there’s, there’s a place for these binders, but I don’t think mitigating DON is the right place or even zearalenone or T2.
Dr. Larry Roth: Mm-hmm
Scott Zehr: 926 cows, Larry.
Dr. Larry Roth: Yep. Absolutely.
Scott Zehr: Ta- T- talk, talk about, talk about that. What, what am I, what do I mean when I say that, Larry?
Dr. Larry Roth: So we’re, we’re talking about a research study in which we had over 920 cows randomly assigned to either a negative controlled diet, no mycotoxin protection, or DTX supplemented to provide that protection. These cows were exposed to a diet that had 1.5 part per million DON, and approximately 150 parts per billion of zearalenone.
So we would consider that to be a high risk for DON, medium risk for zearalenone, two mycotoxins stacked on top of each other, so definitely some mycotoxin issues. And we saw a very nice improvement in milk production and a tremendous improvement in cows getting pregnant and staying pregnant.
Scott Zehr: Yeah.
Dr. Larry Roth: So there, there you go. There you’ve got a large study conducted on a commercial dairy, a dairy that is used to doing feed trials, let me make that comment, so they know how to do things right. The study was blind in that at the dairy, they had no idea which supplement was the negative control and which one had DTX.
They only knew supplement A and supplement B. And we ended up showing a very nice ROI based upon milk production. And dependent upon how you view, uh, the value of a pregnancy, a tremendous improvement in ROI factor when you factor repro in.
Scott Zehr: Yeah, and tell you, the value of pregnancy, that’s, that’s pretty high. Always has been, but I think it’s even higher nowadays. Larry, I appreciate you visiting with us about this today because it’s, I think part of it is almost like a personal mission of mine, but, what we’re trying to accomplish at Agrarian isn’t to replace binders in all situations. Again, there’s a reason those products exist.
We’re just trying to help, uh, bring awareness to the fact that, “Hey, maybe this isn’t the right tool for this job,” right? If I was gonna paint this wall behind me, I wouldn’t start with a hammer. You know? It’s… There’s, there’s a correct tool and there’s an incorrect tool. So I-
Dr. Larry Roth: Scott, if your challenge is aflatoxin, there’s a whole bunch of feed ingredients out there that can tie up aflatoxin. Just be cautious, though, that those ingredients are also reducing the bioavailability of different nutrients.
But if your concern is DON, there really isn’t anything out there that’s gonna tie up DON, which brings us over to the DTX. Zearalenone, there’s a few that can provide some moderate protection. T2, really not anything out there. Ochra, a few, moderate protection. Fumonisin, eh, there’s a few that can provide moderate protection. So Scott, do you want excellent protection or moderate?
Scott Zehr: Larry, I’m wired to want kind of the best when I, when I go out and make these kinds of decisions.
Dr. Larry Roth: Yep.
Scott Zehr: So I wanna wrap up here with, just a, a little back and forth. Again, think maybe rapid fire, but, feel free to, to complete it.
Dr. Larry Roth: Okay
Scott Zehr: So, top of the episode I asked you the question, the manure stiffened up after we fed a binder. Why?
Dr. Larry Roth: Absorbing moisture.
Scott Zehr: So we have research with Cajal et al that shows that binders will bind some mycotoxins, but they’ll also bind B vitamins. They’ll bind vitamin E and amino acids. What about…
Dr. Larry Roth: And minerals.
Scott Zehr: What about DTX?
Dr. Larry Roth: DTX is not a binder. It will not reduce the bioavailability of vitamins, amino acids, or minerals. In fact, we’re gonna improve gut integrity so that we can improve the absorption of those costly nutrients.
Scott Zehr: And Larry, talk to us about inflammation. You know, because at the end of the day,
Dr. Larry Roth: Yeah
Scott Zehr: uh, I, I think the real story here isn’t loose manure or stiff manure. I think it’s we’re dealing with mycotoxins and the negative effects of mycotoxins. And when I think of what the negative effects are, I used to think less milk, less repro. And now I think the negative effects really are more inflammation, more nutrient reallocation towards non-productive purposes.
Dr. Larry Roth: Yep, there you go. I th- I think you nailed it. Inflammation is simply the body’s trying to repair itself due to some insult. It could be pathogens affecting the small intestine, could be mycotoxins being absorbed, could be heat stress. Inflammation is also involved in normal processes such as the cow giving birth and repairing the reproductive tract, as well as gearing up the udder, the mammary gland, to produce milk.
So inflammation is normal. It can be also induced by outside stressors. But basically, inflammation reallocates nutrients away from profitable purposes: growth, milk production, reproduction. Reallocates nutrients to just trying to stay alive. Repair the body and stay alive.
Scott Zehr: Okay. Now I’m gonna ask you one more question, Larry, and it’s probably got a few different answers or a few different parts to an answer, but here we go. So if you could give dairy producers kind of one framework, if you would, for evaluating any mycotoxin product, what questions should they ask before they put it in their cows?
Dr. Larry Roth: What challenges are you seeing in your cows today? Have you been testing for mycotoxins? Do we know that there’s a mycotoxin issue there? And then we would want to ask, are you prepared to use a product that’s gonna reduce nutrient bioavailability, so you gotta feed greater levels of nutrients? Or would you rather feed a natural product that is going to help the body work the way that it should and promote gut integrity and help defend the liver?
Scott Zehr: There we go. Good questions for you to ask the next time you’re thinking about doing something with mycotoxin mitigation. Larry, I appreciate you joining us for this episode. We’re gonna be talking to you again soon about calf, calf raising. So in particular, what we’re putting into that calf on day one, and that kind of excites me because, Larry, it brings me back to one of your favorite sayings, and what is that, Larry?
Dr. Larry Roth: Whatever happens day one, week one, month one of life affects that animal the entire rest of its life.
Scott Zehr: I love it. I… Folks, I did not tell him I was gonna do that, so all I had to do is mention the word day one and Larry, like, he, he knows that. He believes it, he preaches it, and, uh, it’s the truth. So just look it up. But Larry, again, thank you for joining us on this episode of Ruminate This. We’ll be talking again soon.
Dr. Larry Roth: All right. Thank you, Scott.
