During kidding season, lots of goat owners start to worry about ketosis and pregnancy toxemia in their does.
In today's episode, Dr. Robert VanSaun, professor of veterinary science and extension veterinarian at Pennsylvania State University, talks about what causes does to go into ketosis and how that can lead to pregnancy toxemia.
If left untreated, it can ultimately lead to a doe's death. So, we are also talking about how to prevent this potentially devastating condition in the first place.
Full show notes here -- https://thriftyhomesteader.com/pregnancy-toxemia-in-goats/
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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 a particularly timely episode if you're listening to it as soon as it drops, because kidding season is fast approaching, and today we are going to be talking about pregnancy toxemia—or ketosis—with Dr. Robert Van Saun, a professor of veterinary science and extension veterinarian at Pennsylvania State University. And if you've listened to this show before, you've probably heard Dr. Van Saun before talk about other nutritional topics related to goats. Welcome back, Dr. Van Saun.
Robert Van Saun 0:54
Thanks! Glad to be back again.
Deborah Niemann 0:56
This is a really great topic right now. I thought about it because I've been starting to get a lot of questions from people about pregnancy toxemia, or ketosis. First, can you just talk about the name? We hear "pregnancy toxemia" and "ketosis" used pretty much interchangeably. Are they really the same thing? And why two different names?
Robert Van Saun 1:18
Okay, so that's a good point. You know, pregnancy toxemia is sort of the kind of end stage. Pregnancy toxemia as a disease—or ketosis—is a two-stage disease. There's an early stage, where we have an opportunity to intervene and help those does through the rest of their pregnancy. Whereas, once they get into the toxemic stage, it's not a very pretty picture. You know, we're either going to lose the kids. lose the doe, or lose both.
Robert Van Saun 1:55
So, let's go back a little bit. So, where the term "ketosis" comes from is we have to understand how pregnancy—how the doe provides nutrients to the developing fetus or fetuses that she's carrying. The primary energy is earned by the fetus through glucose. And so the doe has to provide glucose in her blood to the fetus. Now, we know that blood glucose in our ruminant animals... They naturally have a low blood glucose content. So, if we think about blood glucose, our blood glucose hopefully is, like, less than 100 milligrams per deciliter. And if we think about dogs and cats and many other species, that's about the same—somewhere between 85 and 110 milligrams per deciliter. However, ruminant animals—normal, healthy ruminant animals—will maintain a blood glucose down around 45 to maybe 80. And so, this is because when we eat, you know, sugar, a sweet treat or something, we can digest and absorb that glucose directly, and so we maintain a fairly high blood glucose. In a ruminant animal, the bacteria in the rumen ferment that glucose. And so, no glucose really comes down to the small intestine to get digested.
Robert Van Saun 3:32
And so, this is a compensatory mechanism of ruminants as they evolved into their ecological niche in life. And so, where glucose comes from in ruminants is one of the end products of fermentation in the rumen is a three-carbon compound called "propionate." So, we talk about the volatile fatty acids; there's three volatile fatty acids. One is acetate, which is two carbons; propionate, which I said is three; and butyrate, which is four. Only propionate can be converted by the doe's liver to the compound glucose. So she has to make her own glucose. And that process is called gluconeogenesis. Now the fetus, they have the capacity... They have the enzymes that can do that. But for whatever reason, Mother Nature decided the fetus's ability to make glucose is shut down. And the reason, probably, is the fetus, if it could use substrate to make glucose, it could grow much faster than maybe mom, or, you know, exceed mom's capacity to handle that. You know, because the growth of the fetus is going to be dependent on how many nutrients it gets from mom.
Robert Van Saun 4:54
So, all that being said, glucose is only transported across the placenta into the fetus through a concentration gradient. So, that means if mom goes glucose-deficient, fetus goes glucose-deficient. So that doesn't make a lot of sense, you know, in terms of survival of the species and ensuring that, but what mom does is she starts to mobilize body fat. And so, what mom does in the late stages of pregnancy is she actually stops or reduces her secretion of the hormone insulin, which helps her tissues use glucose, so that more glucose is available to the fetus. And in place of burning glucose, she starts to burn fat. Well, depending on stress factors, intake capacity—which is a function of forage quality—and many other factors, mom may not consume enough. And so, her energy needs may not be met by what she's consuming. And as a result, she's going to mobilize more and more body fat. The liver processes all that body fat, but the liver can't break down all the fat into just carbon dioxide and water like other tissues. It makes a compound called a "ketone body." And when ketone bodies accumulate to excess, that initiates a state of what we call "ketosis." And so, that's the disease ketosis. So, we talk about in humans "pregnancy ketoacidosis." And so, excess ketone bodies can result in suppression of the immune system; it can result in acidosis, blood acidosis. And this is what gets the doe ultimately into what we call a "toxemic state."
Deborah Niemann 6:56
Okay. So basically, the doe first gets ketosis, and then if that goes untreated, then she becomes—
Robert Van Saun 7:04
Gets into a more serious stage. Yes.
Deborah Niemann 7:06
Okay. That's good to know. I had a feeling those two words did not mean the same thing, even though people use them interchangeably all the time.
Robert Van Saun 7:14
Deborah Niemann 7:15
So, what can people do to prevent this from happening?
Robert Van Saun 7:21
Yeah. So, we're actually doing a project right now looking at pregnancy toxemia in does. And obviously, the first thing is the feeding of the doe. We know that—as I just explained—for the bugs in the rumen to make more propionate... They make more propionate by fermenting carbohydrates, like grains, like starches. So, this is why we often recommend, you know, towards late gestation, starting to add some grain to the diet, to help them produce more propionate and make sure that the energy intake of the doe is adequate to meet her needs so that she doesn't have to mobilize so much body fat and get into the beginnings of this ketosis process.
Robert Van Saun 8:10
So, the two things that are important are, one, recognizing how many fetuses the doe has, because the more fetuses she has, the higher the energy demand she's going to have—and, as I'll get into, the less she's going to be able to eat. You know, when you look at a doe that's got twins or triplets in her, you almost have to laugh in terms of "How does she even walk," you know, "with the immense size of her body?" And if you were able to look inside her, her uterus is taking up most of her abdomen. And so the rumen, where she's fermenting all her feed and processing all of her nutrients, is very limited in space. And this has been shown, you know, historically in terms of intake capacity. Yeah, she could eat a lot of grain. But if we do that, we can cause rumen acidosis, which we don't want to do, and we're afraid of that. But really, the biggest and most important issue is the quality of hay that she gets. And so, a very poor, low-quality, highly mature grass hay is very inappropriate for these late pregnant does. You might want to be switching to alfalfa hay, to get a little bit extra protein, get in extra calcium so that we don't get the secondary hypocalcemia or milk fever issues, and something that's a little more digestible. Or, a really high-quality grass hay, but we've certainly got to be adding some grain to her diet to meet that glucose need. So, dietary formulation, forage quality, is the number one thing.
Robert Van Saun 9:54
Beyond that, in terms of prevention, is just monitoring and managing those animals well. So, the first thing we want to be wary of is body condition score. So, if people understand body condition, you know, we can grade animals on a scale of 1 to 5—with half scores—and that's based on how much fat is in the subcutaneous tissues. In other words, "How hard is it to find the bony prominences of the skeleton," you know? And the reason we're concerned about that is overly fat animals—which is very common in many of our show goats and in our meat style goats. When an animal is overly fat, you know, it has a body condition score 4+ on up to 5, that actually suppresses her intake. Her intake will go down faster during late pregnancy than an animal that's in thinner condition. And so, that puts her into greater what we call "negative energy balance," and that's going to mobilize more fat. And since she's really fat, she's got all kinds of fat to mobilize, so those animals get into a very severe disease consequence called "fatty liver disease" or "hepatic lipidosis."
Deborah Niemann 11:17
So, if somebody has a goat that is overweight—I actually just got this question a couple days ago. Somebody has a doe that, like, got bred a month ago, and she's very—it sounds like—obese, and this woman's like, "What can I do to prevent toxemia?" And I'm kind of like, "Right now? Well, you can't put her on a diet." You know, "You just have to feed her really good-quality grass hay."
Robert Van Saun 11:44
Yeah. Yeah, so that's a real challenge. This has been a big issue in the dairy industry with fatty liver disease and so on. Not so much with the ketosis during pregnancy. With dairy cows, it's more ketosis during early lactation, because of the excess milk and high milk production and the glucose lost milk. You know, we found that overly fatty animals during that late dry period, as I just mentioned, reduce their intake. But if we try and cause body weight reduction in those animals, we actually cause more problems. So, we need to recognize that overly fat and overly thin animals are what we call "special need" animals in the pregnancy. They both can actually get into ketosis and pregnancy toxemia.
Robert Van Saun 12:38
For overly fatty animals, to me, what I want to do is I want to try and feed them just to the energy needs that they need. I don't want them to gain any more body condition; I don't want them to really lose body condition. But I'm probably going to increase the protein, because it seems protein helps us manage ketosis, you know, because amino acids can be used for glucose production, and amino acids are necessary for transport and movement of fatty acids. So, when they mobilize that, they don't get caught up in the liver; the liver can export and help. So, I'm going to be much more cognizant of protein levels in the diet—probably going to be pushing closer to 15% crude protein rather than 12 or 11% for those overly fat animals.
Robert Van Saun 13:28
On the thin animals, we're probably going to feed them to maybe gain a little bit of weight to make sure they've got enough reserves to make it through the early lactation period. And again, probably feed them a little more protein to make sure they have those resources.
Robert Van Saun 13:45
We don't want to stress these girls. I mean, we don't want to be changing or moving them anywhere; we don't want to be regrouping them in a way, you know, any kind of social stressors. We want to make sure that our feeding practices are very consistent, there's not any gaps. Hopefully, we don't get any severe winter storms during, you know, that process, because that could knock some of these animals off feed, and that's the trigger that starts this whole process. So, body condition management of the animal, stress management, and then the diet, as I said, is the number one thing.
Robert Van Saun 14:23
The other thing, of course, is very good observation. We know that these overly fat animals, as they start to enter into ketosis, they start to stock up in their legs. It looks like they get edema in their legs, and they almost start to breathe heavy, and they look like they have respiratory signs. And so, don't discount that as just maybe some early pneumonia because it's cold or something like that. That could actually be the early signs of pregnancy toxemia. The other thing is, if these does start to separate themselves off, and not come up to the feed bunk, and aren't aggressive at the feed bunk, or anything like that, that's one of the first behavioral signs that something's going wrong.
Robert Van Saun 15:11
And what we're doing in our project is, many people may know that if you—especially if you're a Type 2 diabetic or something—you prick your finger, and you can, you know, use a little meter and test your glucose concentration. Well, we have a project that's ongoing right now where we are using those handheld meters for people and testing... There's two types of strips we can use. There's a glucose strip, so we can measure blood glucose. And then there's a beta hydroxybutyrate strip, which is a ketone body—that's the predominant ketone body that we can measure. And so, preliminary work has for the most part validated that we can use these test strips on goats to identify when they are heading into trouble with ketosis, or if their blood glucose is going low. It seems that goats maintain a really low beta hydroxybutyrate or ketone level into pregnancy—much lower than what a typical cow would do. But then, if their blood glucose drops—and we're not quite sure which level it needs to drop to—but that seems to be the trigger that really initiates this overwhelming metabolic change that heads them down this ketosis/pregnancy toxemia, path. So, we're trying at this point to collect lots of blood samples, testing and validating—continuing to validate—the use of the meter, but now trying to find what values are the values that are necessary that would suggest, "Hey, we need to do something with this doe before she gets worse."
Deborah Niemann 17:03
Okay. I was curious exactly how common ketosis is—or toxemia. Because we've had 700 kids now, we've had eight sets of quintuplets, and, knock on wood, we've never had a case of this. So, that kind of makes me wonder like, is it really that common? Or is it kind of a perfect storm with, it's more than just lots of kids, or just a doe that was underweight? Like, does it usually need to be two or three of those things to put all these wheels in motion?
Robert Van Saun 17:37
Well, again, it's gonna depend a lot on the feeding program of the animal. That's the biggest player. When we look at the published literature from all over—from Greece, from Spain, and so on—the average pregnancy toxemia prevalence, or, you know, what percent of animals in a herd would come down with it, it's generally in that, you know, somewhere between 5 and 7%. We've collected 100 and some samples, and we have six cases. So we're right in at, you know—maybe a little less than—6%. However, if, you know, somebody has a bad situation, their forage quality is not what they thought it was, and any other stressors like you described, we could have a disastrous situation where you might have 20 to 25%. I know a practitioner that I've worked with who has a fairly large sheep and goat practice in California; she had one herd where I think almost 60% of the does on this farm were having pregnancy toxemia problems.
Deborah Niemann 18:52
Wow! That definitely makes me think that environment and stress and diet play a really big part in that, then, if you see it so high in some herds, and like—knock on wood again—nonexistent in my herd.
Robert Van Saun 19:09
That's good. I mean, that's what everybody wants to do. Because, I mean, this can be a very devastating disease. And it only takes a couple blocks to kind of unstabilize the process and end up having a big metabolic wreck.
Deborah Niemann 19:26
Yeah, and I know it is a very stressful thing. Like, you have to be watching the doe like a hawk—
Robert Van Saun 19:31
Deborah Niemann 19:31
—once you know she's got a problem. And then you have to be ready to, like, induce or do a C-section really fast in some cases.
Robert Van Saun 19:40
Right. Well, in those cases, and that's... I guess, the point in those cases where the veterinarian with the diagnostics is suggesting either a C-section or induction, you know, depending on where she is in the stage of her pregnancy, you know, that's suggesting that things are getting too far. We want to catch things earlier than that. That's what we're trying to do with the study is... You know, some work out of the U.K. and over in Europe and Greece suggests that a ketone level of .8 is that threshold—and that's .8 what's called millimoles per liter. That seems to be sort of a common threshold that many researchers have used to suggest that those does are in what we call "subclinical stages." You know, so that's where we can come in, we can try and better feed that doe, or we could drench her with some propylene glycol that can be converted to glucose, and things like that to help her recover and regain stability in her glucose metabolism before she gets into a more serious situation.
Deborah Niemann 20:59
There are a lot of people who have asked in the past if there's something that they can use that's more natural than propylene glycol. And I know there's recipes out there on the internet for that sort of thing. But then, I've also heard that not every type of sugar is going to be properly absorbed by a doe who is in ketosis. So, can you talk about that a little bit? Is there—like honey, maple syrup, corn syrup—is there anything else that's appropriate?
Robert Van Saun 21:31
Well, the problem with many of those things is, you know, you're providing the sugar, but—remember what we said earlier—is that sugar is going to get fermented by the bacteria. You know, so that's not doing anything different than what the propylene glycol is. You know, the question there is whether or not are the sugars—like, all the sugars that are out there. We know that there's five-carbon sugars and six-carbon sugars and things like that. Some of those sugars don't get converted to propionate, which means they're not converted back into glucose for the animals. So, that's what we've got to be careful of. White Karo syrup can be absorbed in the mouth. So, that's a good one that you can get some glucose into an animal. We use that in, like, baby pigs that are glucose-deficient because of poor milk production by the sow or something; they'll absorb white Karo syrup directly, just right in the mouth. But you know, I don't know the sugar types, like in honey, and I'd even be more concerned about maple syrup in terms of maybe having sucrose-based sugar types in there, and that's not going to help necessarily with the production of propionate to be used for glucose production in the doe.
Deborah Niemann 23:03
So, if a doe is going off feed, she's kind of off by herself, you've checked her urine and she's spilling ketones in her urine, then the next step would be what?
Robert Van Saun 23:17
Okay. So, the next step is going to be trying to entice her to eat some more. All right? So, if it has to do with forage quality, maybe bringing in some alfalfa hay, adding a little more grain, or feeding smaller grain amounts more often throughout the day. The other thing, vitamin B12 injections could help. That's helps stimulate appetite, plus vitamin B12 is an essential coenzyme in the production of glucose by the liver. So, we use that a fair amount in ketosis cases in dairy cows. Trying to... You know, I guess you've got to know the doe and her behavior. And one way I would think about, maybe isolating her, and, you know, hand-feeding and so on. But if she is a real social creature, and you know, she gets more upset by being separated from the other does, that might make matters worse. So, you've got to gauge that. But, you know, I would prefer watching her and feeding her and having a better handle on what she's actually eating than just sort of leave her in with the other does and she's got to fight with those, you know, for food or anything like that.
Deborah Niemann 24:41
Okay. And then, if you can't entice her to eat, then that's when you would start with the propylene glycol?
Robert Van Saun 24:47
Yeah. You can do propylene glycol drenching. You know, you can mix up a little bit of propylene glycol, about 2 ounces or so. You could add water to it. You could even add some B vitamins to it and things like that. And you don't have to tube her to do it; that's okay, if you're comfortable with that, but you know, you might be able to kind of just put it in the side pocket of her mouth there, in her cheek area, and let her drink it down or something, so it's not so traumatic and you're stressing her out during that process like passing, you know, a stomach tube down or something.
Deborah Niemann 25:24
Right. And then, somebody else asked me this recently, too. Like, is there a maximum time limit that you should give propylene glycol, like five or six days, or ten days? When you say, "No, that's too much"? "Too long"?
Robert Van Saun 25:39
Yeah. So, propylene glycol in excess can cause problems in the rumen with the rumen bugs, so we don't want to overdose. All right? So generally, if these does don't respond well within three days, then I'm going to be looking at some other options. I'll go as long as five days, if she's responding, and I might keep it up for two more days. But I generally don't think you need to go beyond that. If you do, then something else is wrong. And you might want to come in and, you know, have the veterinarian administer some glucose solution or something along those lines—
Deborah Niemann 26:20
Robert Van Saun 26:20
Deborah Niemann 26:22
Okay. And then, at what point do you decide that it's time to induce a doe or do a C-section?
Robert Van Saun 26:30
Well, that might... You know, the things that we'll be looking at is, when these does go into what I'll call the "end stage" pregnancy toxemia, they become dehydrated. So, we could base it off of a blood test, looking at packed cell volume, or just their mucous membranes, and things like that. They also become acidotic. And so, urinary function is going to be reduced. And again, if some blood work is done, they would indicate, like, the anion gap or total carbon dioxide is going to be off. But again, a lot of people don't like to spend the money on those things. And they can't be done right there by the animal—other than the glucose and the beta hydroxybutyrate. So, I would look at those. And if that glucose starts dropping below, say, 30, she's gonna need to either be rid of those fetuses or something. And that's the challenge.
Robert Van Saun 27:37
Now, there is some work out of Portugal from an old graduate student colleague of mine, where they found blood glucose actually goes up to really high levels in late pregnancy toxemia. And their supposition there is that indicates that the fetuses have died, and they're no longer sucking the glucose out of mom, and that's why her blood glucose goes up. And it hasn't been proven extremely well yet, but it's an interesting thing. So again, you know, a really high blood glucose probably is one that would suggest a stronger intervention or invasive process to intervene there.
Deborah Niemann 28:22
Oh, that's really fascinating. This whole conversation has been really interesting, and I think this is gonna be really helpful for a lot of people. I know it's something that a lot of people really worry about, but it sounds like... Every time you're on here, we wind up saying the same thing: If you get the nutrition, right, everything kind of falls into place.
Robert Van Saun 28:44
And, you know, again, that reinforces why... Even though I went on and did my veterinary degree and thought I was going to go out and and help animals, but I didn't get taught the nutrition. And once I was out in the field and saw what was going on, I realized that nutrition was really the most essential part of veterinary medicine. Because we want to prevent the diseases, and it all comes back to starting off with good nutrition.
Deborah Niemann 29:13
Yeah, that is so true. Is there anything else about ketosis or toxemia that you wanted to talk about today?
Robert Van Saun 29:21
You know, it's a devastating disease, and we certainly have to be very cautious. I did a webinar Tuesday night for Extension on reading your forage report. So, you know, what I would encourage everybody to do is, you know, think about spending the money—it's not excessive—but especially for whatever forage you might be, you know, feeding your pregnant does here as we're getting ready for kidding season. And if the neutral detergent fiber—or NDF—content of that hay is above, you know, say 55%, that's probably a forage she can't eat. We want to see the neutral detergent fiber in the late pregnant doe diet somewhere in that 45 to 50% range. So, if they're kidding later March or something—or even early March—we're right now starting to get into that critical intake capacity where those does just can't eat all of that fiber and keep it in their rumen, because the uterus is taking up too much space.
Deborah Niemann 30:39
Right. Well, thank you so much. This is all been really interesting, and I think it's gonna be really helpful for a lot of people. Hopefully help people sleep a little better at night, too.
Robert Van Saun 30:49
Deborah Niemann 30:49
Thanks so much for joining us today!
Robert Van Saun 30:51
All right. Thank you.
Deborah Niemann 30:54
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!
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