Since parasite research in goats is always evolving, I was excited to see that the American Consortium for Small Ruminant Parasite Control has revised their dewormer usage chart. Although most of the dosages have stayed the same from previous chart, there are a lot of new recommendations that you'll find in the footnotes.
We are joined in this episode by one of the authors of the revision, Michael Pesato, DVM, DABVP, Assistant Clinical Professor of Food Animal Medicine and Surgery at Mississippi State University College of Veterinary Medicine.
Dr. Pesato talks about what off-label drug usage means — and what it does not. And he talks about why we should discontinue some of the practices that have been around "forever," such as giving an injectable orally. That means injectable dewormers have no place in a goat owner's medicine cabinet.
We cover all the dewormers, including morantel tartrate — the only dewormer that's a feed additive. It's also one that I've never heard a vet recommend. Dr. Pesato even dispels the myth that combination horse dewormers are combination goat dewormers.
For more information on using drugs off-label, check out the Food Animal Residue Avoidance Databank.
Full show notes here -- https://thriftyhomesteader.com/goat-dewormers/
To see the most recent episodes, visit ForTheLoveOfGoats.com
Want to support the content you love?
Head over to -- https://thrifty-homesteader.ck.page/products/love-goats-tip-jar
For the love of goats! We are talking about everything goat. Whether you're a goat owner, a breeder, or just a fan of these wonderful creatures, we've got you covered. And now, here is Deborah Niemann.
Deborah Niemann 0:19
Hello, everyone, and welcome to today's episode. This is going to be incredibly informative. You know I love to talk about parasites as much as possible, and you probably think that I have beaten parasites to death on this podcast. But I was really excited when I saw that the American Consortium for Small Ruminant Parasite Control sent me an email a couple months ago saying that it updated the dewormer chart for small ruminants. And I noticed that Dr. Michael Pesato at Mississippi State University College of Veterinary Medicine was the person responsible for that. So, I contacted him and asked if he would join us today to talk about the new recommendations for using dewormers in goats and sheep. Welcome to the show today. Dr. Pesato!
Michael Pesato 1:05
Thanks, Deborah. I'm really excited to be here. I think this is a great topic.
Deborah Niemann 1:09
Yeah. And the first thing I want to get out of the way right off the bat is, like: Okay, the reason you have to do this is because most dewormers are not labeled for goats. And so, you know, people are just Googling and flying by the seat of their pants and passing around, you know, old information. And the information on the labels is not even correct, in many cases. And so, it really confuses people, because they think like, "Oh well, everything's off-label for goats. So, we can just do whatever we want, and it's totally okay." So first, can you just talk about what it means to use drugs "off-label"? And the fact that it's not just a free-for-all?
Michael Pesato 1:50
Absolutely. Yeah. And first, I want to say the American Consortium for Small Ruminant Parasite Control—which is the organization that Deborah mentioned had sent an email—is a great organization. Susan Schoenian from that organization and I were the ones that kind of went through and updated that chart, and then Dr. Adriano Vatta from Louisiana State University also had a role in that. So, I just wanted to make sure everybody knows we cross-check and check to make sure that our dosages are correct, that what we're recommending when we're using these products is correct, because it's really important for us in the Consortium to make sure that the most up-to-date, accurate information is available for all of you out there. It's important for us that our producers and our small ruminants enthusiasts know what they're doing with their products.
Michael Pesato 2:31
So, great question, Deborah, about "extra label" and what that means and what that's all about. And so, the challenge with small ruminant parasites is obviously the fact that there's so much resistance development out there. And, although we do recommend utilizing as many products as possible to try to fight off some of that resistance, there are still legal, FDA-approved labels that are on these products. The unfortunate reality for goats is that there's really only one product that has a goat label for the gastrointestinal nematode. So, things like the barber pole worm, Haemonchus contortus. That one product is fenbendazole, which is Safe-Guard, Panacur—those are two of the brand names. The other product that has a label for goats is Valbazen, or albendazole. But that label is technically only for adult liver flukes. So, although it is shown to be effective—or, I should caution myself saying "effective." Because again, with this resistance development activity in a lot of our parasites, the effective levels are kind of decreasing. But, although it may be used—Valbazen, albendazole—specifically for small ruminant gastrointestinal nematodes, the barber pole worm, it's not actually on-label for that.
Michael Pesato 3:44
So, what does that mean? Why I keep saying "on-label" versus "extra label"? Basically, if you use something that is on-label, it is legally recognized and tried and true by the FDA for that animal, that disease process, at that dose, and that frequency of administration, and route of administration, and duration as well. So basically, that product has been tested, certified, approved by the governing body in charge to say that it is efficacious, and we as veterinarians have to follow what drugs we use based on what they're labeled for and who they're labeled for. So technically, if I have a product like fenbendazole—Panacur, Safe-Guard—and it's labeled for goats to be used in Haemonchus contortus treatment, that will be the product I have to reach for first. And as a veterinarian, I have to show evidence that is not effective before I move to a product that is considered extra-label or off-label, which would literally—unfortunately for goats—be every other product on the market. And I could do that as a veterinarian. Again, this is a veterinarian speaking: As a veterinarian, I could prove that by doing a fecal egg count and looking to see that it wasn't very efficacious. Or, I can pull up data to show, "Hey, this product has been tried in this area of the country, and it's not efficacious, and we know that. So, we're going to move forward." Otherwise, if I can't prove that, then me using an extra-label drug is technically illegal. So, utilizing these extra-label drugs without a veterinarian involved consultation-wise is potentially going to be illegal for people that are doing this.
Michael Pesato 5:20
Now, are you gonna get thrown in jail? Probably not. But there is a potential, especially if you're selling food products—milk, meat—from your goat, that you could get in some trouble: fined, slapped on the wrist, etc. Just depending on your state that you're in, depending on the state laws, and what's going to be looked at as appropriate versus inappropriate. But, "extra-label" essentially means that that product is not tried and true for that species, at that dose, at that route, frequency, duration of time for use of that product.
Deborah Niemann 5:56
Okay. So, what are some of the changes? Because like, basically, everything is off-label. So, this is why you can't just pick up the bottle of whatever and say, "Okay, this is the dosage for goats" when you're looking at dewormers, because metabolism of goats is very different than other animals. And so, the cattle dosages don't work, the sheep dosages don't work, and so that's why you have this wonderful chart that shows how much you should use. And at its simplest—I mean, because there's a lot of numbers on the chart. At its simplest, what it all boiled down to in the past was that: 2x everything except levamisole, which is 1.5 times the label dosage for cattle. So, what are the changes that have been made in this last chart?
Michael Pesato 6:46
Yeah, that's a great question. So essentially, one of the big things we wanted to double-check was that our dosaging that we have currently listed was most appropriate. We used several sources. So essentially, what I did was I went through all of the doses that we recommend for use in this product, and I cross-referenced it against other published resources that are out there. So, one of the resources I used is a text called Goat Medicine by Mary Smith, who is a veterinarian and small ruminant expert out of Cornell University. She has a formulary in the back of the text, and I went through and made sure that our dosages kind of met what she recommends in her formulary for use of that product in goats. And then, of course, we went through and made sure that our calculations were all correct moving down the chart, because the goal of the chart is, like Deborah said: There's a lot of numbers, but it's made to be simple. So, essentially you can look at the recommendation for the product, you can look at the weight of your animal, and meet in the middle to get a dose that is most efficacious.
Michael Pesato 7:46
The other big thing we looked at was the bottom section—which, the top is really great and useful. But the bottom section is actually what lists the products. It lists what they're labeled for. It lists withholding times. And so, if you're kind of curious about withholding times, that was one of the big areas I wanted to focus on. Because a lot of this stuff is off-label, I wanted to provide safe withholding times for meat and milk products. So basically, a withholding time is the amount of time that you have to withhold eating that product, consuming that product, as a human being—or marketing that product, if you're marketing it for human consumption—from the last dose of administration for that product. So, I wanted to make sure that what we had listed—because our turret hadn't been updated since 2014, which... Getting to be a long time ago. You know, eight years ago. My big thing was, "I want to see if I need to increase or decrease some of those recommendations for withholding times." They can really make a huge difference in what you select, especially for dairy goat people; they can make a huge difference in what you're selecting for use, because if your withhold time is exorbitant, you can't use that product, because you can't sell your product afterwards. There's going to be residues of medication in your milk or meat, which we don't want to see. So really, we didn't update the dose as much as we did just cross-reference and make sure that nothing has changed.
Michael Pesato 9:11
Deborah and I were speaking before we got started here about how science is always evolving. So, we have to cross-reference, we have to check ourselves, we have to make sure that what we're putting out there is the most relevant information. And Deborah's absolutely right: Our kind of rule of thumb has always been two times the dose of a sheep or a cow dose, because of the metabolism, except for levamisole, which is a little bit more narrow margin of safety—a little bit more risky when you're overdosing—to go with. So, we just needed to make sure that those recommendations were still fitting, and we did find that really our dosage hadn't changed much. We found some miscalculations on the charts that we went through, and actually yes, painstakingly, Susan went through and calculated out every single number on that chart. So, it was definitely a team effort, with Susan cross-referencing a lot of our math. And I was just cross-referencing a lot of our information that was being put out to you guys so that we made sure we had the most accurate information from a veterinary standpoint.
Deborah Niemann 10:09
Yeah. That was one of the things that, like, jumped out at me immediately is that, like, you know, you glance at it, and you're like, "Oh, the chart looks pretty much the same." And then you're like, "Ooh, but, like, all the footnotes!" It's like a whole other page of footnotes."
Michael Pesato 10:23
Deborah Niemann 10:25
That's where all of the good, juicy stuff is.
Michael Pesato 10:28
Exactly, exactly. And that's a really good point: Read the footnotes. It's a wealth of information down there. And you know, yes, you can get your dosages and everything you need from the chart just looking at a quick glance. But the reality is, it gives you some basic information; it gives you, like I said, the withholding times. One of the things I wanted to add to the footnotes is use of some of our anthelmintics—or dewormers—for meningeal worms, because we use them off-label even more so for meningeal worm. So, we actually increase. We go from, basically, two times what we normally recommend for the Panacur or Safe-Guard to five times what we would normally recommend, because of the ability for that product to actually penetrate into our central nervous system. So, there's stuff that is very valuable for you that can, you know, kind of go above and beyond maybe what you were looking at the chart for initially in those footnotes.
Deborah Niemann 11:21
Yeah. And one of the things that I think is really important to get out there—and I just constantly repeat this—is that we're not supposed to use injectables in goats. Can you talk about the reasons why behind that?
Michael Pesato 11:36
Yeah, absolutely. So, one of the most common things that I see in a lot of my clientele, a lot of the producers that I work with, is utilizing products that are not necessarily the most beneficial for the small ruminant and are labeled, honestly, for other species. So, the most common kind of insult I see orally is using horse dewormers—that are labeled for horses and are dosed based on horse weights—or a sheep or goat. Injectable-wise, there are no products that are on-label for a sheep or goat, nothing that's been tested in a sheep or goat, nothing that has been proven to be efficacious in a sheep or goat. But, there are injectable products labeled for cattle and swine. And so, what I'll often see is the use of these injectable products that are used for cattle and swine, and they're given either orally. Which, if that doesn't make sense to you a little bit: It doesn't make sense to me. And I will tell you, I actually thought about that, and I was like, "I don't understand why giving this injectable product orally makes people think it's going to be efficacious." Think about it: It's a totally different route than what it's actually made to do. So, for example, if something's injectable, it's made to be absorbed from the bloodstream, under the skin, or in the muscle. Giving it orally, it goes into the stomach, where there's stomach contents, and eventually acids. A ruminant, of course, has four compartments to the stomach. So, it would have to make it through multiple levels before it would even be somewhere where it can be absorbed or have efficacy against the actual parasite. Because we know that you find these parasites in the abomasum, which is the last stomach before the intestines. So, it didn't make sense to me. I really, like, wracked my brain. And finally, I was like, "You know what? I'm gonna reach out to several people."
Michael Pesato 13:16
So, I reached out to two pharmacologists, and I reached out to Dr. Ray Kaplan, who is the small ruminants kind of guru. One of them. He's in our Consortium as well. Excellent parasitologist. Did a lot of small ruminant parasite research, now at St. George's University, where there's a lot of parasites as well. So, he's keeping himself really busy. And all of the people emailed me back, and basically Dr. Kaplan said, "Absolutely not. Don't use it. Not a good idea to give an injectable product orally." The pharmacologist said, "Well, it may work, but it's going to be greatly decreased in efficacy." Well, if we know anything about resistance development, we know that something that is decreased in efficacy breeds more resistance. So, we don't really want to use something that's going to be decreased in efficacy. That doesn't make a lot of sense. And Dr. Kaplan—who's, like, the guy that I refer to when it comes to making sure we're using the most appropriate product—is saying, "No, don't use it at all." So, I have sang that tune. And that's something that I have taught now to producers, veterinary students, veterinarians alike, that were taught—maybe 15 years ago—it was wise to give an injectable product orally, because we didn't have maybe the necessary products at that time. But we do now.
Michael Pesato 14:28
So, the same thing goes with these injectable products. These injectable products are not labeled to work in sheep and goats; the efficacy is going to potentially be either decreased or unknown. We don't know. And going into the unknown with parasites is never a good idea. Because we already know so much information about the resistance development amongst these parasites, it's really challenging to argue that you should use a product that you don't know if it's going to work over a product that at least you know has some efficacy. And that goes into, for example, ivermectin. Ivermectin, IVOMEC injectable, is the product that's out there for cattle and swine. Well, there's an IVOMEC sheep oral drench. Yes, it's not labeled for goats, but it's closest to goats. Closer than cattle and swine. That's an injectable product. So, err on the side of going with a product that is labeled for a species that mostly resembles, similarly, the goat. Right? So, goats are not small cows; they're just not. Pigs are monogastric; they have one stomach. Goats have four compartments. Sheep and goats, although not the same, are the most similar species. So, you'd want to choose a product that's the closest to that species that you can. So it's all about efficacy, Deborah, when it comes to why you shouldn't use these injectable products.
Michael Pesato 15:43
The other thing we talked about a little bit is withdrawal time. So, if you are a producer, and you're making milk, you're selling cheese, you're marketing your goats for meat production, you do not want to use a product that has unknown withhold time, or is potentially going to be a longer withhold time than what we actually would have for an oral product. So, keeping that in mind is also very important from a production standpoint, that you could really influence the amount of time you have to wait before you could market your products.
Deborah Niemann 16:12
Yeah, this is another huge misconception among people. They think that like, "Oh, if it doesn't say what the withdrawal time is, that just means that they haven't researched it." But, in some cases, it does mean they researched it. And they're like, "Oh, yeah, this is completely unrealistic." Because I think, like, for ivermectin, it's 40-something days and for cydectin injected, it's around two months.
Michael Pesato 16:35
Deborah Niemann 16:35
Like, who wants to milk a goat and dump their milk for a month or two?
Michael Pesato 16:39
Deborah Niemann 16:40
I mean, that's crazy! So even if it did work, like, it's not something that I would want to do. And this is really interesting, because, you know, like you said: Fifteen years ago, giving an injectable orally was something everybody did and everybody talked about. And looking back on it now, I'm going, "Oh, yeah." Like, "That's another one of the things we did wrong that led us down the path of dewormer resistance."
Michael Pesato 17:07
Exactly. Exactly. Yeah. And you know, you bring up a good point about the fact that not having a provided withholding time on the product doesn't necessarily mean that, "Oh, they just didn't research it. They didn't look into it." And I know we were talking about—before we got started—about kind of how those things come about. And really, we mentioned FARAD. So, if you've never heard of FARAD before, FARAD is the Food Animal Residue Avoidance Databank. And so, it is exactly what it says it is. It's a database that provides withholding times to producers and veterinarians alike about products that maybe are not labeled, or used extra-label in those species. And as a veterinarian, I actually can request from FARAD a specific withholding time for that product for that animal that is producing milk, meat—even if it was eggs or honey. Whatever that animal is producing, I can ask for that withholding time.
Michael Pesato 18:00
And withholding times for goats and sheep are often much higher than what's labeled for cattle. So, for example, I'll use a non-dewormer, but Banamine. Banamine, or flunixin meglumine, which is an anti inflammatory, the labeled withholding time is—for cattle—it's four days for meat. For small ruminants, it can be over 21 days for meat. So, if you're going to use that product, don't use what's on-label for cows. Remember: Small ruminants do not equal little cows. That's not the case. And so, utilizing that resource—and the Food Animal Residue Avoidance Databank, FARAD, has a website that has a lot of published withholding times on there. If you can't find one, consult with your veterinarian, and they can find withholding times that are most appropriate for products that have been used extra-label. And of course, hopefully, you've been working with that veterinarian to decide to use that product extra-label before giving it, because as Deborah said, some of these injectables, as well as over the counter medications that are labeled a certain way for cattle, can be very limiting in small ruminants in terms of withholding times.
Deborah Niemann 19:04
Okay, another thing I'd like you to talk about is, you mentioned it super briefly.
Michael Pesato 19:08
Deborah Niemann 19:09
This again, the person I bought my goats from told me to do this 20 years ago, and I know it still gets done a lot, and that is horse dewormers.
Michael Pesato 19:18
Deborah Niemann 19:20
What's wrong with using a horse dewormer for your goats?
Michael Pesato 19:23
Oh, yeah, this is a great conversation. So essentially, the most common thing I'll see, often, is utilizing horse dewormers that are combinations. So, they have things like a macrocyclic lactone—which is a dewormer that is good against the gastrointestinal parasites, like Haemonchus contortus, the barber pole—and something that's good against something like tapeworms. So, what we'll see is, for example, ivermectin-praziquantel. And I won't say the product name, but there is an equine tube dewormer that has that in it. And so, one of the challenges if you look at that product... First off, I've had people falsely assume that those two dewormers are what we consider "combination therapy." That's not true. Combination therapy, when it comes to combating parasite resistance, is the use of different classes of anthelmintics, or dewormers, that have different types of mechanism of action against parasites. So, when I say that it's an ivermectin and a fenbendazole, those products—now granted, those are two, maybe, not the best example. It'd be more like a moxidectin, cydectin, and Valbazen—albendazole. Sometimes, we use three dewormers together—things like a Valbazen, a prohibit—which is levamisole—and then an ivermectin, moxidectin, cydectin. And so, a combination dewormer is not using something that's specific for the worms—the gastrointestinal worms—and something for tapeworms.That's not a combination therapy.
Michael Pesato 20:49
So, that's one misconception. I have people tell me, "Oh, well, I use the horse dewormer because it has the combination effect." It does not. Tapeworms are generally non-pathogenic in adult animals. We do see issues in young stock, so we can see kids and lambs that potentially develop diarrhea; unthrifty appearance; you'll see the pieces of tapeworms, the little grains of rice in their manure; and worst-case scenario, we've seen some of them get obstructed due to the large proglottids—or pieces of rice—kind of building in their intestines. But for the most part, an adult ruminant does not necessarily need to be treated for tapeworms. Other fun fact: The Valbazen, the albendazole, is labeled to treat tapeworms, so you don't really need to worry about using a combination equine product to get your tapeworms; you've got the combination product there already with that Valbazen.
Michael Pesato 21:38
The other challenge with the equine products: They are metered out, oftentimes in these tubes. So, they're metered out to fit a certain weight. For example, most horses are going to weigh anywhere from 500 to 1,000 pounds, depending on, you know, what horse you have. And so, those tubes are going to be metered in hundred increments, potentially—or bigger, if you're getting a larger tube. If you have a 45-pound goat, that is going to be very challenging to dose appropriately. And one of the big challenges we see with parasite resistance is inappropriate dosage of our dewormer. And so, utilizing those products that are labeled for horses, but also dogs, and cats, and pigs, and cattle, are going to potentially lead to increased incidence of resistance due to the fact that it's almost impossible for us to adequately dose those products. Anyone that's used horse dewormers, you know they come out. When you squeeze that tube, you might get more than you bargained for, or you may not get enough; they might spit out half of it out of the side of their mouth. So, if you only get a fourth of what you're supposed to get, you're like, "Oh, that's probably good, because I dosed it at 200 pounds, and it only weighs 50 pounds." That's, like, not even math, right? That's just eyeballing it. And we know that, as Deborah mentioned, that is what we used to do. We used to eyeball it like that. And now, we are where we are with parasite resistance because of that.
Michael Pesato 23:04
So, the goal would be to avoid using products like that. Avoid using your dog or cat dewormer that you buy over the counter. Use a product that is labeled for sheep and goats. I mean, obviously the only one for goats... There's only one. But I'd rather use a sheep product that's oral than using a horse product or a dog-cat-pig-cow product.
Deborah Niemann 23:27
Okay. One of the things that kind of surprised me—and I've noticed that I really never hear parasitologists talk about morantel tartrate.
Michael Pesato 23:36
Deborah Niemann 23:36
I mean, I always kind of assumed, "You know, I don't think that stuff really works." Like, the only time I use it was if I'm doing a combination, because it's category three. It's like, it's either morantel tartrate or levamisole in category three—
Michael Pesato 23:48
Deborah Niemann 23:49
—and so I will use it, like, to fill in that blank if I'm going to do all three classes. But, can you talk a little bit about morantel tartrate? And does it really work by itself? Because it looks like you changed the dosage on that one.
Michael Pesato 24:03
Yeah. Yeah, so that's a great question. So, the morantel tartrate is... So it's a product in the tetrahydropyrimidine class, which is a big word that means nothing really. It essentially, what it does, is it it works to paralyze the worm. And so, several of our products are going to paralyze the worms and expel them alive. Basically, everything except for the fenbendazole, the benzimidazoles—that actually disrupts the energy metabolism—and then our ivermectin and moxidectin will paralyze the worms and actually kill them. Morantel is one of those that's going to expel them alive. That doesn't mean that they're going to be infective once they're expelled alive; it just basically means it doesn't kill them within the system.
Michael Pesato 24:45
In terms of efficacy, it's a really good question. I think, across the nation, efficacy varies in a lot of our dewormers. So, for example, if you look at studies coming out of the mid-Atlantic and the Northeast, you'll see that levamisole is the most—or was. Because these are studies now, one's from 2016, the other one is then from 2008. So, these are getting a bit outdated. And we at the Consortium, I think, are always looking for ways to collaborate and kind of update these studies. But, in the Northeast, you would see that levamisole was most effective. Here in the Southeast, it was moxidectin; it was cydectin. So, prohibit versus cydectin. Morantel, for me... I have a hard time recommending to my clientele to utilize that, especially as a standalone product. I think it's fair to use it as one of the products that you're going to combine.
Michael Pesato 25:35
The reason I have a hard time telling my clients, "Hey, go ahead and use this as your standalone," it is a product that is mixed in your feed. So, it's something that you don't necessarily individually dose with your animals. And I think part of the reason the dosage changed, since it is kind of a feed-additive product, we have to look at kind of what is recommended for use of the morantel. You can imagine, if we talk about the best way to decrease resistance development is to stop blanket deworming—meaning don't deworm the entire group of animals—then you have a product that is actually labeled for goats... It's the second product labeled for goats. I almost forget about it, because I don't recommend its use. It is labeled for goats, but it's labeled to be given in the feed. Well, most producers—unless we're going to separate out all of the animals we've deemed parasite-susceptible, or showing signs of parasitism—and feed them separately, and feed them the morantel separately, and come up with a dose that fits the amount of feed you're using... That's probably gonna be a lot of work for somebody to do. So, the easier thing is to go to a co-op or over-the-counter farm store, purchase the product, and add it to your feed as a regular dewormer. I have a hard time with that, because it is the definition of blanket deworming; it's utilizing that product to deworm the entire herd or flock without any idea of what their current parasite status is.
Michael Pesato 27:02
One of the benefits, however, about it is that the withholding time is zero. So for goats, there's really nothing else of zero withholding time. So, for the dairy people, it may be something to consider utilizing for susceptible populations that, you know, you do separate out and manage a little more intensively. But it's something that's going to require you to do that, and have a separate feed for that animal group, so that they get what they need from that morantel. The other challenge I find with anything that's added to feed or water is that there can be varying amounts of dosage getting achieved by the individual. So, I tend to steer away from utilizing a product that you're just going to add to a feed or water. You know, this is kind of a same vein, but talking about something like a Corid—an amprolium product that you add to water. I almost would prefer susceptible animals be dosed individually, that way I know they're getting the adequate amounts that they need. And morantel, it's really hard to do that with, especially with the way it's traditionally used.
Deborah Niemann 28:07
Yeah. With adults, it's fairly easy to give them a pan of grain, like, off to the side by themselves. But I find with kids—which, they're more likely to have a parasite problem, because their immune system is not as strong—they often freak out when you separate them from the herd. And they're like, "What's going on? Why am I here?" And, you know, heaven forbid, like, you put them in a stall by themselves with a pan of grain; they're really going to freak out and just be running around in circles, and they don't care—
Michael Pesato 28:34
Exactly. "—to eat what you put in front of them." And that stress, that extra stress, is not helpful. I mean, just like you mentioned, Deborah, like, the reason we see a lot of parasite issues in our young kids and lambs is because of the fact that their immune system is not as strong. Well, stress is a natural immunosuppressant. You know, I mean, anybody who's done anything stressful in their life knows that, right? So, you know, we're always stressed when we're going through the hardest times in our lives, and we tend to be sick when that happens. And same thing for our ruminants; they tend to develop increased incidence of diseases and increased problems with stress. So, if separating your animals is going to cause stress... Which, we know that goats and sheep are very herd- and flock-oriented; we know that that separation can lead to increased problems. So to me, it seems like a lot of extra work for very little payout, essentially. And like I said, the only real, I think, core kind of benefit is the fact that there's going to be zero milk and meat withhold with that labeled product at the labeled dose. But you have to kind of ask yourself: "Am I making sure that this animal is getting treated with the adequate amount that I need to give?"
Deborah Niemann 29:43
Yeah. The main person that I hear say that they have used those are people who are brand-new, and they heard that they need to give their goat a dewormer every month, or two months, or whatever the magic number is. And they think, "Oh, well this is so easy. I can just feed it to them." Then, they think they don't have any parasite problems, and then all of a sudden, one day, they do. And they're like... But then they still think they don't, because they're like, "Oh, but I've been giving them dewormer every month."
Michael Pesato 30:08
Exactly. Exactly. And I think, you know, bringing that up, I mean, there's no such thing as a timeline. Like, yes, I will say parasites have a season. You know, we do know that parasites thrive in different temperatures and different humidities. We know Haemonchus contortus, for example, is the heat-lover. It loves it hot. It loves it sweltering. It loves it wet. We know that, and so the peak season—you know, depending on where you are in the country, that can vary. But, you know, for me, I tend to say on the Eastern Seaboard, our peak season is anywhere from April—maybe late March, depending on how nice it is in the South—all the way to October, November, to that first frost. So that timeframe, which is basically half the year, we're concerned about an increased incidence of parasitic disease. And some people will say, "Well, I deworm heavily during that time period." Well, that's maybe not the right choice, you know? We know that 70-80% of the parasites are found in only 20% of the individuals. So, we don't want to be going through and deworming everybody at the same time, because it gets rid of that beautiful refugia concept we talk about, which is having the susceptible parasites within the actual hosts, as well as on the pasture.
Michael Pesato 31:21
So, you know, you're absolutely spot on with that. People that are new to goats, new to owning this type of livestock, may see it as other livestock or pet practices of deworming on a regular basis. No such thing with small ruminants. We've learned that the hard way, unfortunately. And we've had to evolve with that. And so, looking at it, you know, that product is just helping to perpetuate this false thought of, "I need to be deworming on a regular basis." Like you said: What is the magic number? Who knows? I mean, I've heard some people do it every 21 days, because they think that's the life cycle that they need to be catching. I've heard some people doing it at once a month, twice a month. I mean, I had one person that they did it five times a year. I was like, "Oh, my goodness gracious." You know? It just depends on what they're being told. And hopefully, podcasts like this help to kind of spread apart some of that kind of misinformation that's out there.
Deborah Niemann 32:15
So, just in case we have anybody listening who's thinking that, "Hey, I give some kind of a heartworm preventative to my dog every month. How is this different, giving this to my goats every month, too?"
Michael Pesato 32:27
Yeah. That's a really great question. And you know, I think it's something that we don't talk about a lot. And when we come to think about "heartworm preventative," as it's called, it's really given to the dog mostly every month in order to actually, kind of, pre-treat the condition that's already developed in the bloodstream. So, the way that heartworms work is a little different than the way that the gastrointestinal nematodes work for our small ruminants. Heartworms are vector-borne, which means that they travel from an external kind of parasite, pest, something along those lines that passes it to the host animal. So, in the case of heartworms, it's the mosquito. And we know that in endemic areas, like especially the Southeast... We have a lot of heartworm down here in the Southeast. It has also moved up the East Coast, and across the nation. So, it's not something that we just deal with in the South. It's not something we just deal with in areas where there's mosquitoes, you know, all year round. We deal with it in the summer months when there's mosquitoes anywhere across the nation. But those mosquitoes are what's passing that heartworm to the dogs—and occasionally cats. Very rarely, but occasionally, cats do get heartworm. And basically, those mosquitoes, since they are ever-present in the peak season—and of course in other... You know, seasonality-wise in different areas, those heartworms most likely have already established infection and are kind of brewing to cause infection there. We call that "microfilariae." The small, tiny little worms as they're developing into the adult are going to be already there and forming in the dog.
Michael Pesato 33:57
So, this preventative is actually a treatment. And so we have studies now coming out more and more that are showing resistance development amongst heartworms for those preventatives, and some products have, unfortunately, kind of started to fall to the wayside. Just like some of our dewormers in small ruminants that have been used excessively, we're seeing them fall to the wayside because of this resistance development. So, for those of you that think, "Well, I should just be giving ivermectin every month. Like, we do that in our dogs" the reality is that we are seeing the effects of that in dogs as much as we're starting to see it in small ruminants. We've just seen it a lot longer in small ruminants, and the parasite Haemonchus contortus is much more prone to resistance development versus the heartworm. So, each parasite has different ways of developing those resistance genes. And Haemonchus is really good at it—the barber pole worm—so that's why we've seen much more issue there. And it's important to remember that, although we consider that heartworm preventative, it's actually a treatment, and all of our dewormers that we have that we're utilizing in a small ruminants are treatment, not preventative. There's no such thing as an injectable or oral or topical preventative for parasites right now in our small ruminants in the United States.
Deborah Niemann 35:08
Yeah. That is such a really good point, and especially even just about the heartworm medicines for dogs. That they really don't prevent them.
Michael Pesato 35:15
Exactly. Exactly. Yeah, absolutely. And I think that's something that, you know, I think a lot of people don't necessarily understand that. And why would you? You know, we call it a "preventative," but the reality is, it's actually treating what is an existing infection.
Deborah Niemann 35:28
Yeah. Well, thank you so much! This has been really informative. I think that a lot of people will find this really helpful. Is there anything else that people need to know about the new guidelines?
Michael Pesato 35:38
Yeah. No, thank you first, as well, Deborah, for allowing me to be here today and talk with your audience. I think it's great that you do this, and I'm a huge supporter of the podcast and having people and kind of give information that is reliable.
Michael Pesato 35:51
Yeah, the one thing I want to say: You know, we talked a lot about extra-label drug use early on. And I wanted to stress that, when using a product extra-label, using it for an animal that's not on the actual label, or using a dose that's not on the label—for example, using the two times or one-and-a-half times the dose for goats—we need to make sure that you have an established veterinarian-client-patient relationship. So work with your veterinarian. I'm a veterinarian. I obviously love veterinary medicine. We're here to help you. Let us be your partner; let us work with you to make sure that your animals are healthy. You know, we don't want to necessarily control what you do, but we want to be able to provide you with guidance on how to do things in a legal and, you know, hopefully as efficacious way as possible. So, try to establish that veterinarian-client-patient relationship best you can. That makes that extra-label drug use legal, and it allows us to provide you with those withholding times that you can get through FARAD, the Food Animal Residue Avoidance Databank. It allows us to legally provide you with that when we have that relationship established.
Michael Pesato 36:48
So, I'll leave you on that note. I'd like to again, thank you so much, Deborah, for having me. And if you guys ever have any questions or concerns, you can always reach out to me via email. My email is MEP—so "M" as in "Michael," "E" as in "elephant," "P" as in my last name, Pesato—323 [at] msstate [dot] edu.
Deborah Niemann 37:08
Thank you so much. It has been great having you here today.
Michael Pesato 37:11
Awesome. Thank you.
Deborah Niemann 37:14
And that's it for today's show. If you haven't already done so, be sure to hit the "subscribe" button so that you don't miss any episodes. To see show notes, you can always visit ForTheLoveOfGoats.com, and you can follow us on Facebook at Facebook.com/LoveGoatsPodcast. See you again next time. Bye for now!
Transcribed by https://otter.ai