Today’s podcast digs into the dogma and new thinking about liver abscess development in feedlot and dairy cattle. The entire June 2024 Journal of Applied Animal Science was devoted to the liver abscess phenomena which is estimated to cost the US beef packing industry at least $400 million dollars each year. While liver abscesses in traditional beef and beef X dairy feedlot cattle have been linked to high-starch diets and ruminal acidosis, Rezac et al (2014) suggests similar liver abscess incidence in lactating dairy cows, which suggests re-evaluation of this problem and the potential link to intestinal integrity issues in young calves due to early-life health problems like scours.
Tune in for this literature review with Agrarian Solutions Vice President of Nutrition Dr. Larry Roth, and learn how early intervention to defend and protect cattle from day one can reduce the prevalence of liver abscesses and improve herd health.
For more information on this topic or to learn more about the Agrarian programs that can protect and defend cattle contact us at [email protected].
🎧 Listen now to set your herd up for lifelong success!
Scott Zehr
All right. Hey, welcome back to Ruminate This with Agrarian solutions. I’m your host, Scott Zehr. Great to be back for another episode today with Dr. Larry Roth. And, today we are going to be diving into, Larry, what I would call almost like a buzzword topic in the industry the last number of years, as we’ve seen an ncrease in the beef on dairy calves. Right?
And that buzzword I think is liver abscess. Or should say buzz phrase. But it’s not just, you know, a, buzz phrase if you would, there’s some concerns from the packer side of things, right. It causes some issues there. And I think that’s why everybody’s talking about this, right.
We still want to be able to kill these animals. You and I’ve talked about this, I guess one on one before too. There’s maybe more going on than the traditional school of thought that, Hey, these animals are just fed a high, maybe starch diet for a period of time, which causes these liver abscesses.
And I, think that’s probably still happening to some degree. But you’ve brought some, research to my attention that you’re going to talk about today that it says, Hey, wait a minute. We see similar things going on in the dairy side. So we’re not feeding a super high starch level to these dairy cows.
We kind of balance them a little bit different. So why would we be seeing that? And are there some things we should be looking at? Maybe from a young age, you like to tell us what happens day one, week one, month one affects that calf for the rest of his life. So what are your thoughts on those comments?
Dr. Larry Roth
All right. Scott, you’ve, you’ve touched on a whole variety of subjects there, and I would agree that this is a very big, the liver abscesses is a very big issue in the cattle feeding world. It’s estimated that each year liver abscesses cost the beef packers around 400 million in terms of lost carcass weight, time because they have to stop the processing chain while they’re cutting extra away. And all of this.
And we also know that liver abscesses in feedlot cattle reduces average state daily gain, feed efficiency and, a hot carcass weight. So definitely it’s, it’s a major economic issue. We also recognize the liver as being the body’s biochemical factory, at every age, every age. And so I think that’s why when we have liver abscesses are factory is damaged. Let’s think of it that way.
Cattle don’t perform as well. And there’s a very good issue of the journal of Applied Animal Science from June of this year, 2024, 17 different papers in it. And the traditional dogma Scott has been cattle get ruminal acidosis, pH falls down. It isn’t just lactic acid is total organic acids.
And with that low pH we lose some of the rumen lighting. And consequently we have a break in the castle wall, wherever you’ve heard that before, and bacteria get into the animal and cause liver abscesses. Traditionally, we’ve thought that there’s these Fusobacterium, that’s their genus, that they’re the ones that are the cause of all of this.
Well, I’m going to go ahead and say that probably the foremost researcher on liver abscesses is Dr. Nagarajah at Kansas State University. He’s researched this subject for a long, long time. And several years ago, he published a paper that says, if you look at these liver abscesses, you do a cultive and God, if you’ve ever seen a liver abscess and you think of doing the cultive, you know, it’s kind of a gross thing, but you know, somebody’s got to do it.
You do this, take the cultive and the microbial profile has a striking resemblance to what we find in the small intestine. There’s salmonella there, there’s some E. coli, there’s other organisms. Well, that kind of starts to challenge our thought that it’s mainly fusobacterium that cause this problem.
So, you know, we’re always trying to, as researchers, develop models so that we can evaluate things rather than wait for something bad to happen. And in the case of liver abscesses in the general feedlot population, let’s purposely drop the ruminal pH in some experimental animals and see what happens.
Well, interestingly, some researchers have done that and what they find is that unless there are significant fusobacterium populations, the ruminal acidosis does not lead to significant liver abscesses. So what does that mean? That means that you could have ruminal acidosis, lose part of that rumen lining, and unless your Fusobacterium is high, you’re not going to get liver abscesses.
So, people have had Tylan forever, or maybe I should be scientific and say Tylosin phosphate. And that has been a very effective antibiotic for controlling liver abscesses. But guess what? Tylan costs money. And for people who are into the organic market or the natural market, they can’t feed Tylan.
Well, if we’re really trying to push these cattle, that means putting more starch into the diet. The more starch we put into the diet, the greater the chances of having a ruminal upset, a low pH. So then we look at forage levels and types of forag. And, you know, Scott, we do, effective fibers on dairy diets all of the time. And now beef people are starting to look at that because it isn’t just what percentage of roughage, and we can have another whole conversation on what is the word roughage, but it’s not just roughage.
It’s not just the percentage of roughage, it’s the type. So we’re coming back to the effect of fiber. What are we doing to, number one, increase rumination, because we get the saliva to serve as a natural buffer. And the more fiber we have with the diet, we kind of slow the rate of intake a little bit.
And we’re also finding that the bulk density of steamed flake corn plays a big role. The greater the bulk density, the lower the incidence of liver abscesses. So if we can gelatinize the starch, we get a full fermentation of that starch, but it’s just a little bit slower. So there’s some neat things that’s going along with, with all of that.
So in the past, it was all about ruminal pH, was all about fusel bacterium. Now we’re starting to understand really, there’s many different factors that come into play. We’re also starting to understand it isn’t just Fusobacterium. It’s different species of Fusobacterium as well as different species of bacteria that come into play.
So just when we think we got things figured out, we find out, no, we don’t have it figured out and it’s a little bit more complicated than what we thought.
Scott Zehr
And it seems like that’s true for just about everything too. Right? To me, that makes sense that it’s, it’s probably not just one thing. It’s probably not just Fusobacteria. There’s going to be other factors.
So you touched on the effective fibers. So I want to shift that over, you know, thinking about these dairy cows. We do balance for effective fiber, right? The last thing, if you’re a nutritionist, you want to hear as a, client saying, Hey, we got, cows full of acidosis.
So, I think we watched that pretty close. And you mentioned when they do the liver abscess cultives, right? They’re finding salmonella, they’re finding E. coli. So talk to us about the dairy side of that. And, you had some, literature that touched on the dairy liver abscess stuff too, you made reference to, you want to go into more detail on that? Please.
Dr. Larry Roth
You bet, you bet. So let me back up. If we look at a typical lactating dairy cow diet, high production cow, starch content is going to be, you know, anywhere as maybe 24, 28%, maybe we really push it, we go up to 30. If we look at a traditional feedlot diet, starch is probably going to be like 60 to 65.
Now, there’s some that are feeding more byproducts, and so it’s going to be a little bit lower, but then the same could be said on the dairy side. And we put a whole lot more roughage as a percentage of the diet into the dairy diet. But yeah, we’re still concerned about acidosis. Because think of how much total starch a top cow is going to be eating.
They’re probably going to be eating more corn than a 1,500 pound steer in the feedlot, potentially, could be, okay? So it’s all about, not just percentage of starch, but total starch that comes into play. Well, I believe it was 2014, a group of researchers out of Kansas State University, the lead author was Rezac, went to a great lake and they didn’t identify just which slaughterhouse it was.
And over three days, they looked at 1,461 dairy cows, called dairy cows. And what they found was that 32 percent of those cows had a liver abscess. Well, Scott, what we said before was the dogma has been that it’s high starch diets, it’s ruminal acidosis that caused the problems. Well, I just cited, you know, the percentages of starch and yeah, I would say we do a better job of controlling rumen pH or at least acidosis on the dairy side than the feedlot side.
But still 32 percent had a liver abscess. 18 percent of those cows had a severe liver abscess. So how does that all jive up? But only 10 percent of those cows, the total population, only 10 percent had rheumatitis scars. In other words, scarring from having had a very low pH at some time. So 10 percent have a scar, 18.5 percent have severe liver abscesses, and 32 percent have liver abscesses. How does that jive? And how does that work out?
Scott Zehr
It certainly challenges the status quo of what we traditionally thought about, it is this, and this is the problem. And antibiotic treatment is the answer. With something like Tylan.
Dr. Larry Roth
Exactly. And then some other researchers and they haven’t really published their work. But they have cited it are finding liver abscesses in calves as young as three weeks of age. So Scott, what, what am I famous for saying the digestive tract lining is like a council wall. It’s responsible for keeping the barbarians and the digestive tract and out of the body.
Well, what’s one of the problems that we have with these dairy replacement calves pre weaning? Sometimes we get scour. Sometimes we get coccy. And we get a break in that castle wall and we have opportunities for bacteria to get into the blood and float around, and that’s what the veterinarians call septicemia. And the bacteria can end up in the liver abscess.
So here’s my question, Scott, the 32 percent of these cows that had liver abscesses, and remember only 10 percent of the whole population had rheumatitis scars.
Scott Zehr
And this was 1400 and some cows. Right?
Dr. Larry Roth
Yep.
Scott Zehr
1440.
Dr. Larry Roth
… so it isn’t like we just went out and did 10 of them.
Scott Zehr
Right.
Dr. Larry Roth
Were those cows carrying those liver abscesses in essence, since they were calves?
Scott Zehr
Well, yeah, I mean, if 30, 32 percent had a liver abscess and only 10 had rheumatitis scars, well, do the math. 22 percent of them came some other way.
Dr. Larry Roth
Yeah. So here, here’s my question. What was interesting in this study, I mean, it was just down at the slaughterhouse. So they didn’t have the reasons for why these cows were culled.
Scott Zehr
Yeah.
Dr. Larry Roth
Was it because they didn’t breed back? Was it because, some other disease or reason, laminitis or whatever? Well, again, the liver is the body’s biochemical factory. And if our biochemical factory has some level of damage, is that cow going to be more likely to have ketosis? Is that cow more likely to just be a, here’s a fancy word for you, a poor doer?
Scott Zehr
Yeah.
Dr. Larry Roth
And I think the answer to those questions is yes. So let’s put all of this together. I’m thinking that a lot of these liver abscess issues may originate very early in life, with scours. And those abscesses kind of linger along over time. And the animal doesn’t perform like it should. I mean, I just cited data a little bit earlier than in feedlot cattle who have liver abscesses, they don’t gain as well. They’re not as feed efficient and a lighter carcass weight.
Well, those same things show up in a dairy cow, lower production. And not getting pregnant and staying pregnant. And it was interesting, the author who reviewed all 17 articles in the Journal of Applied Animal Science, identified about 10 different areas of research for the future.
The last one that he cited was evaluating the effect of early calf health on liver abscesses. Scott, this all really became a big issue in 2021 and 2022 as we started having more beef on dairy calves come into the harvest chain. We started to see that liver abscesses in beef on dairy varied anywheres from 20 to 80%. 20 to 80% of the animals had a liver abscess.
Now, anytime you got a big variation like that, it tells us there’s an opportunity to manage the biology and get an improvement. If it was all up there at 80%, we would say, wow, maybe we can’t do anything. But the point of it is, if it’s 20 to 80%, why are some at 20 and why are some at 80? Then you look at Rezac with dairy cows, and we start to say is early calf health.
Now, one of the challenges that we have, you know, we can do ultrasound to look at lung lesions.
Scott Zehr
Yeah
Dr. Larry Roth
Evidently, the ultrasound does not do a very good job of identifying liver lesions, so we’re not really able to early on identify which calves have liver abscesses, and that would really help us, I think, from a research standpoint as well as a management standpoint. But I guess, Scott, I would like to humbly challenge the dogma and say, I recognize that ruminal pH, I recognize that ruminitis is a key factor for liver abscesses in feedlot cattle.
But I would also like to suggest that early calf health and more specifically scours, could be a factor causing liver abscesses very early. And I think this is true both on the beef side. And on the bee pond dairy side. Plus Scott, we still have a fairly significant number of Holstein steers that come into the feedlots.
Scott Zehr
Well, you know, you mentioned the, that range of 20 to 80%. I mean, to me that, I guess it’s not that surprising, to see the range, right? Because, well, most dairy farms in the U.S., I mean, do a really good job of taking care of their calves, right? However, if it’s a terminal calf, does it get the absolute best colostrum that a Holstein heifer calf or Jersey heifer replacement calf would get?
So is it getting the number one colostrum? Is it getting it as timely as the replacement cap does? Do they get the protection of a dose of say, convert gel, like we have a lot of clients use, for that, you know, right when it’s born. So, yeah, I mean, that would, to me, that kind of helps explain the reason why there’d be such a big range, right?
Dr. Larry Roth
So it’s Let me tell you a little anecdotal story. I used to work for a major animal nutrition company. And I was working with a fellow who was feeding straight Holstein steers over in Wisconsin. On a whole corn diet, there was a pellet, very minimal roughage being fed. And trying to make a long story short, I went through and evaluated their records that came from the Packer, very well known Packer.
And I looked, I did this on like 1,200 steers. This guy was feeding out like 2,500 Holsteins a year. And his liver abscess incidence was like 5%. Now what this guy was doing was he was buying Holsteins from anywheres from, oh, a day old to five days of age. He had, some Amish raising these calves. They were using the milk replacer that my employer sold. And so we were doing some consulting on both the calves and on these steers.
But Scott, 5 percent liver abscesses. This guy had exceptional health on these baby Holstein calves. And he was consistently selling these Holsteins 14 to 15months of age. I think his overall average was something like 40 percent prime, which for Holstein’s at 14 to 15 months is outstanding.
So I give you that story as an example that if we manage early calf health, I really think we can improve performance and we can reduce these liver abscesses. Because again, the bias against Holstein steers is, well, they’re all going to have a lot of liver abscesses. Well, that’s because of things that you cited earlier.
So often it’s the Holstein bull calf that doesn’t get the colostrum, doesn’t get the care, you know, the rest of the story, and they’re pretty disposed to these issues. So, you know, I encourage people to go get this Journal of Applied Animal Science from June of 24, look at it. There’s some very good articles talking about trying to develop some models to induce liver abscesses.
And by and large, it isn’t successful unless there’s a significant Fusobacterium population present. Tylan still continues to be about the best way to control liver abscesses. But even then we’re still 30 to 60 to 70 percent liver abscesses. So, the problem is there. It’s multifactorial. It can happen due to many different reasons. There’s many different organisms that are potentially causes. It’s a significant economic issue.
So Scott, I’m going to challenge the industry to look at managing these calves differently from day one. be it the beef calf, the beef on dairy, the Holstein steer, dairy replacements. Again, whatever happens day one, week one, month one, it’s going to affect that animal the entire rest of its life. Not just in terms of respiratory, but here in terms of liver abscesses.
400 million dollars a year is costing the packer. What’s it costing the feedlot? And Scott, let’s go talk about the dairy industry. We’ve talked about dairy cull rates. We’ve talked about dairy replacements. What percentage of those animals have some degree of a liver abscess? Yeah, and predisposing that animal to leave the herd early.
Scott Zehr
You know, I think Larry, we have, would you say a saying at Agrarian and we call it Defend and Protect for a Lifetime.
Dr. Larry Roth
Exactly.
Scott Zehr
If anybody wants to reach out to us [email protected] and, and we can share some of the research articles that Larry mentioned today. But also, we really do, I want to say subscribe to, believe in, and promote the concept that, Hey, we, with our technologies, we have an opportunity, with our cell wall deficient bacteria, with our IGY antibodies to help these animals from day one, week one, month one, and then, and then beyond. You know, one of the things that we haven’t brought up is, Larry, you, you mentioned, the calves with the liver abscesses as early as three weeks of age, right?
So you mentioned the liver abscesses that were called and they found salmonella and they found E. coli. And it’s because of a breach in the castle wall, mycotoxins. What’s the contribution of mycotoxins to degrading the castle wall, leaky gut…
Dr. Larry Roth
Exactly.
Scott Zehr
…bacteria get in, that liver has to detoxify all of these mycotoxins and filter them. What kind of toll does it take on the liver when she’s dealing with high levels of mycotoxins?
Dr. Larry Roth
Absolutely. We know that mycotoxins have a negative effect on liver health. And again, we’re damaging the body’s biochemical factory. We could be predisposing the animal to these liver abscesses. I mean, it’s an exciting area to look at, you know, I remember as a grad student looking at liver abscesses at five 30 in the morning at the packing plant. So I don’t necessarily want to go back to doing that. But I think for somebody starting out in the industry, there’s a tremendous opportunity to look at again, defend and protect the calf from the very beginning.
I think there could be an opportunity with some of these technologies. You mentioned the cell wall deficient bacteria, the IGY. I think there could be a tremendous opportunity to help these cattle have lower incidents of liver abscesses. And by extension, both the cattle feeding business, as well as the dairies.
Scott Zehr
You know, I’d like to think, I guess, because I’m proud to work for Agrarian and I believe in what we’re doing and how we fit into the industry. It’d be great if we have the solutions to some of these problems. But I will say just in general, I’ve got to believe that the answers are out there.
We maybe haven’t totally uncovered them yet. Maybe it’s because we don’t totally understand where everything is coming from yet. But I have to believe that more antibiotics is not the answer. I really truly believe that.
Dr. Larry Roth
Absolutely. Yeah. No, it’s got there’s some, some very interesting technologies that are coming along. And again, what I find exciting is the variations that we see with liver abscess incidents. And I was just talking about my cattle feeder friend with Holsteins over there in Wisconsin, 5%.
Scott Zehr
Yeah.
Dr. Larry Roth
Then other incidents where it goes up to 80. When you’ve got that big of a range, that means there’s something biologically that we can address.
Scott Zehr
Yeah.
Dr. Larry Roth
It’s exciting.
Scott Zehr
It is. It is. Well, Larry, let’s keep fighting the good fight. Defend and protect for a lifetime. And, again, if, any of you have any questions about that comment, defend and protect for a lifetime, or would like to, have us send you the research that Larry has cited in today’s episode, feel free, Reach out to us [email protected] and we will get that to you.
Dr. Roth, I appreciate you taking the time today, as always kind of giving us some things to think about and, certainly, you know, from my personality standpoint, I appreciate the challenging of the status quo to the industry. I think that’s always a good thing when, when somebody is saying, Hey, let’s, maybe let’s see if there’s a better way to do this, so.
Dr. Larry Roth
There you go.
Scott Zehr
Appreciate your time, Larry. Thank you.
Dr. Larry Roth
All right. Thank you, Scott. Bye.
Scott Zehr
See ya.
