Iodine Deficiency in Goats

As I've received more messages from people with kids born hairless or with goiters, I've become more interested in the topic of iodine and goats because those symptoms occur in kids that are iodine deficient.

You don't usually hear anyone talking about iodine and goats unless the topic of kelp comes up, and then the conversation can swing wildly between people worried about deficiency or toxicity. In today's episode, I am joined again by Dr. Robert VanSaun, Professor of Veterinary Science and Extension Veterinarian in the Department of Veterinary and Biomedical Sciences at Pennsylvania State University.

We talk about symptoms of iodine deficiency in adult goats, as well as newborn kids. We also take a deep dive into providing kelp for goats and how labels don't always give you the information you need.

Full show notes here --  https://thriftyhomesteader.com/iodine-deficiency-in-goats/

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Transcript

Introduction  0:03 
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  0:18 
Hello, everyone, and welcome to another episode. Today is going to be really interesting. We're going to be talking again to Dr. Robert Van Saun, a professor of veterinary science and an extension veterinarian in the Department of Veterinary and Biomedical Sciences at Pennsylvania State University. And we're going to be tackling another nutrient that is very important to goats that we don't hear a whole lot about, and that is iodine. Welcome to the show today, Dr. Van Saun.

Robert Van Saun  0:48 
Thank you, and glad to be back again.

Deborah Niemann  0:51 
In case you missed them, we also have episodes with Dr. Van Saun covering selenium, and copper, and colostrum, and I think a couple other things.

Robert Van Saun  1:01 
Zinc.

Deborah Niemann  1:02 
Yeah. So, this is really great. I always learn a lot of the little, nitty gritty things. And with iodine, there's not nearly as much information out there about that as there are some of these other more common minerals. But, I wanted to talk about this because, in the last couple of years, I've been getting an increasing number of emails and messages on social media from people who have baby goats that are born without hair, or who are born with a large goiter on the front of their throat over their thyroid gland. And so, I don't know if this is becoming more common, or if it's just I'm becoming more aware of it, but I thought it was definitely something that we should talk about today. So, let's just get started with the basics, like we usually do, and that is: Why is iodine important?

Robert Van Saun  1:50 
So, iodine is another one of what we call the "microminerals" that's required; it's an essential nutrient. And so, it's needed in very minute amounts—usually, you know, just a few milligrams a day when we think about iodine concentration in the diet. The general recommendation for goats is somewhere between 0.5 and 1 part per million. So really, quite low. I mean, if we think about what we discussed before, you know, you're on the order of magnitude of selenium at 0.3 parts per million, but well below the requirement for zinc or copper, which were, you know, up in the range of, for zinc, 40 to 50 parts per million, or copper at 10 to 20 parts per million.

Deborah Niemann  2:40 
Okay. And then, how does iodine affect the body?

Robert Van Saun  2:45 
So, iodine has basically one major purpose, and that is to feed an essential nutrient to the thyroid gland. And the thyroid gland is basically your metabolic controlling organ in the body. So, the thyroid gland makes what we call "thyroid hormones." These are iodinated proteins—in other words, proteins that have iodine as a component. The functional protein is what we call "T3" or "triiodothyronine," and then the precursor to that is what we call "T4" or "thyroxin." So, if somebody is hypothyroid, they might be taking thyroxin supplements to help maintain a normal thyroid level. What happens is T4 gets converted to T3 in the cell—and that's dependent upon selenium status. We talked about that a little bit when we talked about selenium. So, an animal or a person who is selenium deficient could also end up being hypothyroid, even though their thyroid is perfectly functional. But then, within the cell, the T3 protein acts upon the cell machinery and maintains sort of the RPMs of the body—you know, the basic metabolic activity. It drives how much glucose you're consuming, or you're burning. And that's why, generally, hypothyroidism is associated with gaining of weight, and hyperthyroidism is associated with weight loss. So, any part of the body that is actively metabolic is under thyroid influence. So, hair growth and skin is very sensitive to thyroid changes, and then just our what we call "basal metabolic rate." Basal metabolic rate is influenced by our genetics. You know, there's some people who, proverbially, can eat the entire cake and not gain weight, and some people can look at the cake and gain weight. And so, that's all of how that thyroid hormone is working with their body machinery and how high-revving their body metabolism is.

Deborah Niemann  5:12 
Okay. So, are there any natural sources of iodine in a goat's diet? Because it doesn't sound like they need a lot.

Robert Van Saun  5:19 
No, they don't need a lot. And there's a very unique cycling of iodine in the environment. The ocean has quite a bit of iodine in it. And hence, this brings up a topic we'll address in a little bit about kelp and kelp-based products. But iodine will be evaporated, and then come down with rainwater, and fall onto the plants, and get incorporated into plants. Now, the problem we have is, up until a few years ago, measuring iodine in the body was really quite difficult. We didn't have routine measurements of iodine concentrations in blood, so that's why what often is done is to measure, you know, T3 or T4 concentrations. And many times only one is measured, and so that doesn't give you a full picture. And then, of course, the thyroid gland itself that makes T3 and T4, it is stimulated by a part of the brain called the "hypothalamus." So, there's a stimulating hormone called "thyroid-stimulating hormone" that gets released. And of course, that gets feedback from all parts of the body as to whether metabolic rate needs to be increased or decreased and all of that—metabolic activities. So, iodine is taken up almost exclusively by the thyroid gland; the thyroid gland is extremely efficient in taking up iodine. And so, we never measured iodine levels in, like, the liver, which is what we normally use for trace mineral analysis, and even in blood. But now, with the new technologies—with mass spectroscopy—many of the labs that have historically measured trace minerals in blood and tissues are now starting to offer iodine. So, we're just starting to get a better handle on what recommendations are in terms of what the iodine concentration in serum or in tissue might be.

Robert Van Saun  7:29 
I guess I didn't finish where they're getting it from. So, forage will have some iodine. But most of the iodine is either coming from iodinized salt that's available, or from mineral supplements. Now, generally, unless you're around the Great Lakes region—and so part of Pennsylvania, New York, and you know, those states surrounding the Great Lakes—those are iodine deficient belts. And there's some serious iodine deficiency in South America and in many other countries of the world. But, for the most part, we are able to provide sufficient iodine through our forage and any kind of supplements. Now, I've had situations where people haven't fed iodinized salt. And so, that's led to some problems. And we're starting to recognize that the Boer goat phenotype is very iodine dependent. And we see much more iodine deficiencies in the Boer goat than I see in most of the other animals.

Deborah Niemann  8:43 
Oh, that's interesting! One of the pictures that someone sent me recently of a newborn with a goiter was a Boer kid.

Robert Van Saun  8:49 
Yeah. And that's an important point is... You know, just little tidbits of information: For the most part, when a doe is pregnant, she passes on most of her trace elements to the developing fetus, because the fetus needs this. As we talked about, most of the trace elements are not in sufficient quantity or concentration in milk, and therefore they have to build up a store in their liver. Well, iodine does not do that, because iodine is, like I said, about 95 to 98% trapped by the thyroid gland itself. And so, newborns with enlargements in the throat region—that's an enlarged thyroid gland. Because the thyroid has expanded the number of cells to try and capture the little bit of iodine that's there. So, the thyroid rose in response to iodine availability. And the abnormally large thyroid is called a "goiter."

Robert Van Saun  9:54 
And we can see goiter in two scenarios. We can see goiter with iodine deficiency, and we can see goiter with iodine toxicity. So, the only way we can differentiate those two... Well, now we can measure serum iodine. And with iodine toxicity, we would expect an extremely high serum iodine concentration, and deficiency, very low. But, we would have to look at the thyroid gland under the microscope itself. Because in toxicity, what we see is greatly enlarged follicles—they're called "follicles." These are structures lined by cells that help bring the iodine in and then trap the iodide in protein complex called "thyroglobulin." And so, we'll see—in terms of a toxicity—we'll see massive increases in thyroglobulin within the thyroid; whereas in deficiencies, we see a massive increase in the number of follicles within the thyroid. So, we can differentiate toxicity from deficiency through a histologic evaluation of the thyroid gland itself.

Robert Van Saun  11:08 
More typically, I expect in most of our production animals, including goats, to see iodine deficiency. And have—like you, Deborah—have seen or heard of a number of cases, not only in goats, but in cattle. I recently had a situation with a veterinarian in Longhorn cattle where they had goiter in all their newborns. And it turns out that that was a genetic problem. There's another aspect to that, where they were unable to take up that iodine in the offspring. But that iodine deficiency in offspring—they're born dead, they have the enlarged thyroid, they're hairless, generally—and that's pretty classic. And something we can easily fix with just some iodine supplementation through iodinized salt or through even painting some iodine onto the skin. Iodine is absorbed through the skin quite readily. The only time I've had toxicities: I had it in some horses. And that was just due to a high-iodine kelp-based product that had extremely high iodine concentration. And what we saw in that case was some facial deformities in the newborn foals.

Deborah Niemann  12:37 
So, one time—or maybe, I think, it has happened a couple times—somebody has emailed and said, "I had this kid born that had no hair and this huge enlargement on the front of the throat, and then a twin was born completely normal." How common is that? And does that still mean iodine deficiency?

Robert Van Saun  12:57 
Yeah, that's still does. You know, again, as I mentioned, the iodine isn't shared very well. I mean, obviously, it has to be shared somewhat by mom for survival of the fetus, because the fetus has actually a higher metabolic rate than mom does. So, it needs iodine; it needs a functional thyroid. However, in cases of twins, we can see one affected by goiter, and one not. Now, it could be that the thyroid in what is perceived as the "unaffected" one actually does have enlarged follicles and things, it's just that it got the better blood flow from mom and took up the iodine better than the other kid in the uterus. It depends on where they are relative to the nutrient-rich blood coming back through the placenta.

Deborah Niemann  13:49 
It kind of reminds me of, like, how you can have triplets or quads, and you can have one that weighs half as much as the others. It's just that, unfortunately, that poor kid did not get as much nutrients through the placenta as its siblings did.

Robert Van Saun  14:06 
Yeah. And so, you know, that becomes a problem. As we know, in goats, if anybody has seen a goat uterus—a pregnant goat uterus. You know, if you had a goat that prolapsed her uterus or something like that, or in a necropsy case or something, goats—like sheep and like cattle—have a special kind of placentation called "cotyledonary." And so, there's a kind of a bulge coming up from the lining of the uterus, called a "caruncle," and then the fetal placenta wraps around that. And, actually in sheep and goats, it burrows in the middle of that; whereas in cattle, it kind of wraps around and it's got, like, a Velcro attachment. Now, that is the only exchange of nutrients that occurs. It doesn't occur across the entire placenta. So, if you have a crowded uterus, there's only so many caruncles in mom's uterus. And there could be, you know, one of the fetuses that's positioned in a place where maybe there was previous damage and caruncles were lost, or, you know, scar tissue or something like that. Or, they were just pushed out; they didn't grow quite as fast as the other siblings within that cohort, and they're going to be shortchanged.

Deborah Niemann  15:36 
One thing that I think is kind of challenging is, like, if somebody has a goat that has a miscarriage... So, like, you have these kids that are born, and they're fully formed, but they're tiny, and they have no hair. Where's the line where you would say, "If a goat is this far along in her pregnancy, the kids should absolutely have hair"?

Robert Van Saun  15:57 
There is a defined point in time... Like in calves, we expect the hair to come in in the last month, month and a half of pregnancy. And so, the hair does not develop there until sort of that very end of gestation. And so, if they're basically more than 4 months along from breeding, they're probably going to have hair, or start to have a lot of hair.

Deborah Niemann  16:32 
Okay. So, taking us back a couple steps: You mentioned that either iodine deficiency or toxicity could cause a goiter. But if you're looking, would that only be in an adult? Like, when you have kids born with a goiter, is that always deficiency?

Robert Van Saun  16:48 
Essentially, yes. I mean, I can't completely rule that out, because if mom is ingesting a toxic level, you know, it doesn't transfer efficiently. It does transfer, and there could be enough, but that's really stretching it. I would say, you know, probably in 99% of the cases, it's gonna be an iodine deficiency in the newborn.

Deborah Niemann  17:16 
Okay. And then, when we were preparing for this interview, you mentioned that you're seeing more iodine problems, because there are quite a few kelp-based minerals on the market now. Can you explain what's happening there?

Robert Van Saun  17:33 
Well, that's an intriguing one. You know, because as I mentioned earlier, kelp is considered to have fairly high iodine content. And so, the use of kelp, generally, would result in more than adequate amounts of iodine—assuming they're consuming an appropriate amount—or potentially toxic amounts. Where I'm seeing the problems is generally poor supplementation all around in terms of very little mineral supplement, or not using iodized salt, or something along those lines.

Deborah Niemann  18:11 
Okay. So, when you talk about iodized salt... I just want to get this clear, too, because a lot of people think that they need to have a salt block in addition to loose minerals for goats. And most nutritionists would say, "No, you don't. Your loose minerals is the only source of salt that should be available."

Robert Van Saun  18:31 
Yeah. And that's correct. If we are expecting our goats to consume their trace minerals, which would include iodine, in a trace mineral salt package, then we should not provide any other salt. Because, as we said, animals don't have specific appetites for all the minerals; they really only have an appetite for meeting a sodium requirement. And so, the sodium requirement drives the intake. That's why we can use salt to control intake of various compounds. And so, if you have two salt sources out, or three—you know, we didn't talk about, but sodium bicarb. You know, putting baking soda out, just white salt, or the red salt—the trace mineral salt—your goats, they may or may not eat enough of the red salt to get the trace minerals that they need, because they're only trying to meet their sodium requirement.

Deborah Niemann  19:31 
Okay. And, since you mentioned baking soda, I want to throw in that, like, your goats should not be consuming large amounts of baking soda. If they are, you need to look at your overall feeding program.

Robert Van Saun  19:41 
Yeah.

Deborah Niemann  19:41 
Normally, they shouldn't be consuming any. Like, it's just kind of there, like, you know, when you have Tums in your cabinet just in case you need it.

Robert Van Saun  19:49 
Yeah, well, in the dairy industry, we put out free-choice baking soda as more of, let's say, a monitor to see if the rumen system is staying healthy. You know, I mean, what we're talking about is animals that get into a situation where they're eating a fair amount of grain or large grain meals, and they get the drop in pH in their rumen. So, this would be, like, after milking, if you're feeding in the milking parlor with goats and just feeding two big, you know, starch-based meals a day, there's a good chance that they're going to have a drop in pH. And, if they're not consuming enough fiber sources to help buffer things in terms of the chewing activity, the secretion of saliva, they're going to need some additional buffering. Now, a goat's probably not as bad of a situation as a dairy cow. But, you know, when we think about, if we add even up to 4 ounces of bicarb, we're really not changing the pH of a 60 gallon rumen in a dairy cow very much—and similar with a goat. But, because the sodium can act as an alkalizing agent in the blood, it's thought that they'll eat more sodium. And hence, you know, if there's free-choice baking soda out there, they may hit that harder to help adjust the inner acid-base imbalances that are occurring with some minor rumen acidosis. And so, if we see a group of animals—whether they be dairy cows or dairy goats—really eating the baking soda quite a bit, or even eating dirt or something like that, then that's telling us there's probably something wrong in that rumen. And it's probably a pH issue, and we need to reevaluate the diet and what they're eating and what they're sorting out and things.

Deborah Niemann  21:53 
Yeah, that's a good point. Okay, so what have we not covered?

Robert Van Saun  21:58 
Well, typically, what you've got to worry about with iodine is the source of iodine. The common source of iodine in most of your mineral supplements is calcium iodate. And that's a very stable iodine form, because iodine is highly soluble. So, like sodium iodine or potassium iodine—which is your light salt. You know, if somebody has some sodium problems, and they need to decrease their sodium intake, they'll use light salt rather than regular salt. Salt is basically sodium chloride, whereas light salt is a blend of sodium chloride and potassium chloride or potassium iodide. You know, the iodized salt will have potassium iodide, and potassium iodide or sodium iodide, basically, just with moisture in the air, will leach out. And so, if you're putting out some kind of iodized salt and leaving it out, if it's not a calcium iodate source, the iodine content is going to disappear very rapidly, especially in moist, you know, humid conditions or getting rained on. What others have done is there is an organic form of iodine. It's a big long word, but the short of it, it's usually expressed as EDDI: ethylenediamine dihydrogen iodide. And that is an organic form—very stable. And that has been used in mineral supplements to actually help with foot problems in cattle.

Robert Van Saun  23:02 
Now, if you're working with dairy goats, and you're harvesting milk, you've got to be cautious with iodine supplementation, especially with kelp, because the government regulates iodine concentrations in milk. That's why there are all kinds of standards and regulations on iodine-based teat dips, because humans drinking the milk are much more sensitive to iodine intoxication, like horses. And so, the government will evaluate and monitor iodine concentrations, and I don't remember what the PMO for milk is, but it's somewhere in the range of, like, 300 parts per million or something like that in milk you're not allowed to exceed, otherwise your milk is considered tainted.

Deborah Niemann  24:42 
Oh, interesting!

Robert Van Saun  24:44 
Yeah. So, that's one of the concerns I have with kelp-based products, is the labels on many of these products. The only requirement on the label is to provide the minimum concentration of iodine—not the maximum concentration. And so, when you have a kelp-based product, many of these ocean kelp coming out of, you know, seawater, they could have 700, 800, 1,000 parts per million of iodine, and the label they just say 400 parts per million. And that's all they have to guarantee. So, if you couple feeding a kelp-based product, using iodine teat dips, having iodine in your mineral supplements, you can easily start to push it too far.

Deborah Niemann  25:38 
Yeah, that's really fascinating. That's the first time I've heard somebody talk about the potential for iodine teat dips increasing the iodine level of the goat's blood, but it totally makes sense if you're dipping their teats in this substance twice a day that they're gonna wind up absorbing a lot.

Robert Van Saun  25:56 
They absorb it across the skin, as we said. You know, in deficiencies, I've had people take about an ounce to an ounce and a half of Betadine and just paint it on the back or so of a goat or a sheep. And they'll absorb that iodine right on through.

Deborah Niemann  26:16 
So, this is kind of a goofy thing that I heard, and it was about humans, not goats, but it just makes me wonder if this is at all legitimate. Somebody was saying that if you paint iodine, like, on your forearm, and it disappears, that means that you're iodine deficient. But, it kind of sounds like that's just what we do. Like, skin is just gonna absorb it. And it doesn't matter whether you're deficient or not.

Robert Van Saun  26:43  
Yeah, I've heard those statements before. And I haven't seen any credible science to document that the rate of disappearance on the skin is associated with, you know, the iodine level—because again, we had a hard time measuring iodine directly.

Deborah Niemann  27:02  
Yeah. And you said it's only just within the last few years that we've really been able to measure it well. So...

Robert Van Saun  27:08  
Right. And we're talking about serum iodine, the actual iodine itself. 

Deborah Niemann  27:12  
Right. Yeah. 

Robert Van Saun  27:13  
And not the iodine proteins T3 or T4.

Deborah Niemann  27:18  
Okay. Yeah, that idea has been around for probably longer than we've had the ability to actually measure iodine in the blood. 

Robert Van Saun  27:25  
Oh, yeah. Yeah.

Deborah Niemann  27:25  
So, it sounds like just an idea that somebody came up with that sounded like a good idea.

Robert Van Saun  27:29  
Yep. Seems reasonable, but you know, there's no documentation about it.

Deborah Niemann  27:35  
Yeah. Okay. This has been really interesting. Is there anything else that people need to know about iodine?

Robert Van Saun  27:43  
Umm, no. I mean, that's... From a nutrient standpoint, it has, you know, one primary function, you know, your metabolic rate. But it certainly can affect hair coat; it can affect rate of growth; it can affect milk production. Matter of fact, before... In dairy cattle in the 19... I think it was the 1940s. Before the whole advent of the technology that we had in the 1980s, and forward of bovine somatotropin, where we were using an actual growth hormone that could stimulate milk production, they used to iodinate the protein for milk called "casein," and then feed iodinated casein to dairy cows to increase milk production. 

Deborah Niemann  28:34  
Okay. 

Robert Van Saun  28:36  
And that just reinforces the whole idea that, you know, iodine is a major driver of metabolic rate.

Deborah Niemann  28:44  
Right. Now, I had read somewhere—I think it was probably, like, in the ruminant nutrition book—that the toxic level of iodine was something like 100 times more than the amount that they actually need. But, when they say that, they're talking about, like, that's how much iodine would actually kill a goat. And a goat would actually be developing symptoms, like a goiter or something like that, long before it got to that point?

Robert Van Saun  29:09  
Yeah. So, you know, that brings up a good point of, you know, what is actually the defined endpoints when we talk about these kind of things. And so, you know, in terms of the disease, we think of disease mostly in the framework of infectious diseases, so, you know, having a bacterial or viral disease, or so on and so forth. But, the same concepts hold for nutritional diseases. So, you can have, basically, you know—we've all heard now with the pandemic—asymptomatic carriers, you know, of the virus. Well, you can have an animal that's asymptomatic, you know, doesn't show any clinical signs, but heading towards either deficiency or toxicity, okay? And the only way we're going to find that is by measuring and having good criteria to say, "Okay, below this threshold means this toxicity or deficiency is occurring." Then, as that deficiency or toxicity of iodine gets more severe, we start to get into early stages of disease that might be, you know, scruffiness of the hair coat, you know, maybe some hair falling out and things, and then it'll progress. Goiter is what we consider "clinical deficiency" or "clinical toxicity," then mortality or death is the ultimate endpoint. Right? So, you know, generally, iodine isn't very toxic. It will cause disease, but it doesn't cause mortality. And so, when you hear these things—like you mentioned, 100 times the requirement—that's not necessarily a toxic value. Okay? What that is is an MTL: maximum tolerable level. And that's the way the scientists compare apples to apples across various nutrients; the maximum tolerable level is that concentration of that nutrient of concern—iodine—that can be fed and consumed by an animal for up to three months without causing death.

Deborah Niemann  31:33  
Oh, that's a good thing to know.

Robert Van Saun  31:35  
Yeah. So that's generally, when we talk about toxicities or higher levels, we're actually talking about maximum tolerable levels. Levels that can be tolerated up until about three months. And that's sort of the period of time that's been used for comparisons. But, some nutrients—especially, like, toxic nutrients, like selenium and things like that—you know, it's not far above that maximum tolerable level that death can ensue.

Deborah Niemann  32:07  
Right. One of the things that I am not super happy about with some of the kelp-based minerals is that they tend to have... One of them in particular has an extremely high level of copper added to it. And I emailed the company and said, you know, "The copper in this looks scary high," especially because goats love kelp. Like, anybody that's ever put kelp out, you know the goats eat it like candy. 

Robert Van Saun  32:31  
Mm-hmm.

Deborah Niemann  32:31  
And, they sent me a study, and it was only three months. And the liver levels of the goats for copper at that point was—according to what I've heard—really high. Like, it was, like, 500. But they said it was fine, because there were no lesions on the liver. And I was kind of like, "Uh, yeah, but you only did this for three months, and it was already 500." Like, maybe there would be lesions next month. 

Robert Van Saun  32:58  
Right. Yeah, so that's always a concern. My bigger concern with most of the kelp-based products is, you know, kelp is highly touted as having very what's called "bioavailable" minerals in it. And it's probably because most of the minerals are incorporated into protein, so they're basically what we call "chelated" minerals, and they're not going to be affected by the rumen environment that much. However, you know, when you do look at some of the analyses of these kelp-based products, other than iodine, most of the other minerals are at fairly low concentrations, you know, because there's not a lot of selenium in the seawater and so on. And so, you know, that's one of the challenges is, unless they supplement or fortify the kelp with other sources of minerals, they're not going to have it very well-balanced; it's going to be really high in iodine, but it's not going to be adequate in many of the other trace elements. And so, you know, fortification is appropriate from the level of, you know, trying to level everything off, although it's going to be really hard to fortify at the level of iodine respective to the other nutrients. But then, what's going to have to happen is the intake is going to have to be restricted in some way. And as you said, you know, most animals seem to like the kelp, and it seems very palatable. And so, that becomes a problem. And, you know, how do you restrict intake? Well, you're going to either have to add a whole pile of salt to it or something, you know, or limit the amounts that are available for the animals.

Deborah Niemann  34:40  
Yeah, that's the thing that kind of scares me, too, about the kelp-based minerals—or just people thinking that, like, they can just use kelp—is that the amount that the goats would have to eat would be huge. And then, by the time they eat enough kelp to get enough selenium and other minerals, they would have gone toxic on the iodine, like... 

Robert Van Saun  35:02  
Well, they would have certainly gotten more than they need on the iodine side. You know, we've addressed this in a couple of different of the episodes where, you know, all the minerals and the vitamins are not necessarily always balanced appropriately relative to each other. And part of that's because of the variation of mineral content in the forages that these mineral supplements are trying to balance against. And so, I can't cast too many stones at the manufacturers, because they have a heck of a hard job to try and... You know, they're not going to make an individual supplement for every single farm or goat farm, you know, in a state or something. You know, they have to come up with something hitting the middle of the road, right?

Deborah Niemann  35:48  
Right. 

Robert Van Saun  35:48  
And, we just need to be aware of that and appropriately either limit certain supplementation or add in some other supplementation to make the best balanced diet that we can for the goats.

Deborah Niemann  36:00  
Yeah. I think that is a really great summary of not only this episode, but, like, all the episodes we've done on minerals. And I've tried to tell people that. Like, there is no single mineral that's going to be perfect for every farm, because they're all different. You know, like, I always use the example of the farm that was 4 miles away from us for the first 19 years that we lived here. And we had problems with copper deficiency that they did not have, because we had sulfur in our well water, which they did not have. And they had a problem with vitamin E deficiency, because their goats were all on dry lot eating nothing but dry hay—which does not have a lot of vitamin E in it—whereas our goats were on pasture, which is lots of green stuff, and they were doing great with vitamin E.

Robert Van Saun  36:45  
Right. Right. That's exactly it. You know, I mean, the aquifers are different; you know, even if you have farms next to each other, it might be a different water source. Just the the topography, how the rain moves through the soil, the amount of organic matter, pH, whether you lime or not... I mean, there's so many variables here.

Deborah Niemann  37:08  
Yeah. And so, that's why I love doing these episodes with you, so that people know, like, "Okay, if I see this symptom or that symptom or whatever, then my goats might need a little bit more of this one nutrient because of the unique conditions on my farm." 

Robert Van Saun  37:24  
Yeah. Yeah so, you know, just to highlight with iodine: I mean, really, the most sensitive indicator is going to be babies born with goiter, because that's going to happen before mom has the goiter. So, the babies are going to be sort of the canary in the mine for that problem. And then, if you don't have babies, then you know, watch the skin and hair coat and certainly keep iodine on your list.

Deborah Niemann  37:55  
Yeah. Awesome! Thank you so much! This has been really informative, and I think it's going to help a lot of people. Thanks so much for joining us again.

Robert Van Saun  38:02  
All right. You're welcome.

Deborah Niemann  38:04  
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