Ep. 098: Feeder Style, Dominance, and Stress in Group-Fed Horses – What the Research Says

Episode Notes

Could something as simple as how you feed your horses be affecting their stress levels and relationships within the herd?

On this episode, host Katy Starr chats with Dr. Karen Wimbush, long-time professor and equine welfare researcher at Ohio State ATI about:

• How feeder spacing impacts herd hierarchy and horse behavior
• The surprising reason dominant horses may actually feel more stress than submissive ones at feeding time
• Tips for reducing conflict and stress in group feeding set-ups

Everything is a tradeoff. Whether you’re feeding horses in dry lots, pastures, or shared pens, this episode offers practical takeaways and insights that every horse owner, barn manager, and caretaker should tune in to.

🎧 Listen now on the Beyond the Barn podcast

Have a topic idea or feedback to share? We want to connect with you! Email podcast@standlee.com

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*Views and opinions expressed by guests are their own and do not necessarily reflect the view of Standlee Premium Products, LLC.*

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Research Dr. Wimbush shared during the podcast:

• “Effects of feeder style on behavior and plasma cortisol concentrations in group-fed horses” - https://www.sciencedirect.com/science/article/pii/S2590286523000435
• “Effect of Pen Size on Stress Responses of Stall-Housed Horses Receiving One Hour of Daily Turnout” - https://www.sciencedirect.com/science/article/abs/pii/S0737080620304573
• Acclimation Reduces Stress in Adult Horses Tied in Visual Isolation” - https://pmc.ncbi.nlm.nih.gov/articles/PMC6285647/

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Connect with Dr. Wimbush at wimbush.4@osu.edu or learn more at her University page. 

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Read full episode transcript

Katy Starr (00:01):

Hi, I'm Katy Starr and you're listening to Beyond the Barn. Join me on this journey as we bust equine and livestock nutrition myths and sit down with some of the most intriguing experts from across the country. We'll also take you behind the scenes of how premium western quality forage is grown and brought to your favorite farm and ranch retail store. I'm so glad you're here.

 

Katy Starr (00:27):

I want to take a moment to share some news and extend sincere thanks to someone who's meant a great deal to the Beyond the Barn podcast. Dr. Tania Cubitt will no longer be joining me as co-host. I'm so grateful for the wisdom and experience that she's shared with all of us over the years. Personally, much of what I've learned about equine nutrition has been through her mentorship. It shaped how I approach these conversations, and I'll carry that forward as we continue to explore new topics and expert insights on the podcast. Subscribe and tune in as we'll be introducing some new partnerships in the near future. Welcome back to another episode of Beyond the Barn. Joining us today is someone who spent her life working with and studying horses from just about every angle. Hands-on in the barn and in the research lab, Dr. Karen Wimbush grew up on a hobby farm in Maryland where her interest in animals started early. Thanks in part to her dad, who was a veterinarian. She got her first horse at 11 and eventually earned her instructor certification at Morven Park, wanting to dig deeper into the science behind horse care, she went on to earn her Bachelor's, Master's, and PhD in animal science. She's now been a professor at Ohio State, ATI for nearly 30 years, where her research focuses on practical welfare focused ways to improve how we care for horses. Dr. Wimbush, thank you for joining us today.

 

Dr. Karen Wimbush (01:53):

Well, thank you for having me, Katy.

 

Katy Starr (01:55):

And so, before we get started on our topic today, I do want to remind our listeners that any of the topics we cover on the Beyond the Barn podcast are more generalized and not specific to any individual horse or any specific situation. Be sure to always work with your veterinarian and nutritionist before making any drastic changes to your horse’s feed program. Or you can reach out to us and talk directly with our PhD equine nutritionists on any specifics that you would like to know. So, Dr. Wimbush, would you tell us a little bit about your background with horses and where you grew up?

 

Dr. Karen Wimbush (02:28):

Sure. I grew up in Western Maryland and like you said, my dad was a vet, so we always had animals. I grew up on a 50 acre farm, although we mostly raised beef cattle. I started, of course, we'd ride with our dad when we were really little kids. We'd go out to on all the farm calls and things like that. And we always had cattle and things like that. But I guess I really fell in love with horses. And we actually had a group, a family pony when I was five. And so, I was really the only one that really liked the pony a whole lot.At that point in time. And so, I was the one that got my first horse at 11. And my siblings, they kind of didn't, weren't that interested in horses, I guess, until my younger sister came along.

 

Dr. Karen Wimbush (03:11):

So, of the four siblings, my younger sister and I were the riders and the people that had the horses. So, growing up, I got my first horse at 11. She foaled when I was think, I think 13. And I raised that foal up and competed at in eventing and actually owned that horse until she was 29.5 and she died in Ohio, so she only had one owner her whole life. And of course I have had other horses and things like that too. And you know, just working with animals is really kind of my passion.

 

Katy Starr (03:41):

That's awesome. And eventing, was that kind of your style of your discipline that you kind of liked competing in and everything?

 

Dr. Karen Wimbush (03:48):

It was. So, of course we grew up just riding around the farm, Western saddles, English saddles, whatever. And then when I got fairly serious about making the equine industry my career, I decided to go to Morven Park International Equestrian Institute. And of course that's very classical eventing, three day eventing, dressage, show jumping, and so, on and so forth. I started doing local events and things like that with my first horse. Well, my second horse really the one that raised as from a foal and from Morven Park we just really branched out into really appreciating the disciplines of dressage and cross country and stadium. And through the years, of course, I've taught and coached. I was employed at Stevens College in Columbia, Missouri for my first equine, really my first equine teaching job. And so, I coached the hunt seat and combined training and dressage teams as well as teaching a variety of riding courses and things since I had my instructor certification from Morven Park.

 

Katy Starr (04:45):

That’s awesome. And so, what kind of drew you to your interest in your field of study and everything as you were working through your degrees and everything? What kind of led you down that path?

 

Dr. Karen Wimbush (04:58):

That's a good question. I had a really varied research background. My master's dissertation, or thesis I should say, was on the actually yeast culture supplementation and growing quarter horses. So, we were kind of looking at bone density and how it related to phosphorus absorption. Of course, a lot of the feed companies wanted to test their products and so we were using a very common yeast species. And so, basically it didn't do anything. I hate to say it because yeah.

 

Katy Starr (05:27):

I mean that's part of research, right? Sometimes you're finding if it works or it doesn't and that's what it's all about. Yeah.

 

Dr. Karen Wimbush (05:33):

Well the one thing we did find that it did improve feed efficiency, which of course in the horse world people are usually not too concerned about feed efficiency because they're happy to spend lots of money to provide the nutrients for their horses. So, that was really the only thing we found there. And I came out of a University of Missouri research lab working with Dr. Wayne Locke. And so, we had a big fescue research component at University of Missouri because tall fescue is such a problem. And so, I kind of led into looking at some dopamine antagonists to remedy fescue toxicosis in our pregnant mares. And then my PhD work really was looking at compounds, particularly altering the dopamine. Dopamine is a brain chemistry or chemical. And so, by altering dopamine we could advance the mares to cycle earlier in the year. So, I kind of went from a nutritional endocrinology background into working with how do we get our mares cycling.

 

Dr. Karen Wimbush (06:31):

And so, that really opened up reproduction as a huge interest. And then of course my real interest has always been teaching, you know, getting what we've learned out to horse owners. And so, when the job came open at Ohio State ATI, which is a two year hands-on teaching program, that seemed like just the perfect fit because it was a perfect marriage of working with students and getting them out to work in the industry as soon as they were finished with their degrees here. So, that really kind of led more into applied management and how we could look at, at potential problems that we would see in the industry and go, okay, let's do a little research project so we can find out what's best practices for horse owners.

 

Katy Starr (07:13):

Right. No, that's excellent. And another fun thing that you kind of do that you shared with me is that you own working bred Australian Shepherd dogs. Can you share just a little bit about that and how you work with them?

 

Dr. Karen Wimbush (07:26):

Sure. I don't know about you, but often the more you are involved in the industry professionally, the less time you have to do those things on the side. And so, dogs were always, I mean, you know, because I love all animals and to me, I'm old school, so if you were a rider, you were also a trainer. We didn't have money and our parents didn't go out and buy us already trained horses. So, obviously from a training standpoint that problem solving, how do you work with an animal? How do you teach it behaviors you want? What are those behaviors that are instinctual in animals? And so, you know, I kind of fell in love with Australian Shepherds because they really are, I mean, they have a usefulness, they have a job in life and that is to work livestock and to help you, you know, on your farm or ranch.

 

Dr. Karen Wimbush (08:12):

And so, I got my first Aussie, I was really into probably more obedience. And then that branched off and morphed into being very competitive in dog agility. And then 25 years ago, I think I got into my first herding dog. I needed to build some confidence in an obedience dog that I had and branched out into herding. And it just changed as far as what I want to do with my dogs because the complexity of the behaviors associated with each individual livestock that you're working with, but also the individuals within a group add into that mix a whole other species, the predator i.e., the dog that now has to listen to the person. It is so complex. It is so dynamic. It is so problem solving focused that it truly is intriguing. So, of all the dog sports, I would say herding is definitely the hardest to learn. And I'm still learning and I still go to clinics and things like that. I still take lessons periodically when I'm bringing up a young dog or I run into a problem with the dog that I have. And there you are scratching your head going, Hmm, how can we solve this? And so, I think that comes back from just really being totally infatuated with animal behavior.

 

Katy Starr (09:30):

Yeah. Well, and I feel like this leads us so well into the topic of our discussion today, because behavior has a lot to do with it in part of the research that we're going to be discussing. And so, as we go into this, we're going to be discussing mainly your research involving the effects of feeder style on behavior and plasma cortisol concentrations in group fed horses. So, tell us a little bit about what inspired this study.

 

Dr. Karen Wimbush (10:02):

I would say this particular research, you see a lot of different feeder styles. And we have always, one manager would come to ATI and they would use trough feeders and another one would have individual pans and they would put the pans in a circle, then they would put the pans hanging on posts. And so, at some point you're kind of like, which of these is the best choice when you've got a dynamic, particularly a dynamic group of horses? Not that our horses change every day, but you've always got additions and subtractions from a herd group. And so, how does that change that dynamics of eating, you know, or feeding your group horses. And since more and more people are sitting or I hope thinking that it's really healthier for a horse to be outside rather than being stall kept. And so, realistically it's easy to feed individually when they're in stalls, but it's probably not the best management practice from a horse standpoint and a horse's welfare standpoint to be standing and in a stall the majority of their time. So, how do you group feed horses?

 

Katy Starr (11:06):

Right. And I think that's what's also very interesting about all of this is the research that a lot of you are all doing. We've taken what we normally have with horses, what horses, wild horses are used to doing and we've put them into our world, right, to be able to ride and show, compete and all of those things. And with that you have to learn to do some different management changes, but at the same time, not everybody's situation is going to be exactly the same. And not every horse is going to be exactly the same. And we kind of have to take what you guys are doing in research and see how can this be applied in our own environment with our own horses. But I think it's helpful because it kind of gives us some insight as to what's going on, almost chemically, I guess in the horse.

 

Katy Starr (11:55):

But then also just being able to make some of these observations with behaviors and how they interact with other horses. Because you have this social dynamic that they need, but at the same time there are certain restrictions that also cause some chaos and stress for them when they are with certain horses in certain situations. And so, it's this, this balancing act that's a little bit challenging. But I think the research I think helps us understand a little bit better, more and more the further research that we do. And so, obviously many horse owners that have multiple horses, they do feed in groups unless they are stalled individually. So, what common challenges in group feeding situations were you kind of hoping to better understand or address through this study?

 

Dr. Karen Wimbush (12:42):

Sure. I mean, one of the biggest concerns when you're feeding in a group is are the individuals getting what they need? And so, you know, you're basically saying, okay, I'm going to feed everybody in the group three pounds of concentrate grain, i.e. grain, and I'm going to dump them in the troughs and everybody's going to, you know, come up and eat. Yeah. But the dominant horses, obviously they're dominant and they're probably more likely to get more of the resources. So, they might not have a weight gain problem, but the submissive horses in that group may be that horse that always seems to be a little on the thin side. And then what are you going to do? Are you going to pull that horse out every day to feed them? If you're in a large stable situation, it's fairly easy to rearrange groups. So, you can pull that submissive horse out and put them with other submissive horses.

 

Dr. Karen Wimbush (13:28):

Certainly we've got some submissive adult horses that wind up in our yearling pasture because that's a good fit for them. Because those yearlings are still adolescents. You can adjust. But a lot of boarding farms or a lot of owners may not have that option. They've got one pasture, they've got five horses and they're either going to have to make the value judgment or the decision to, yes, I'm going to spend the extra time every time I feed these horses to bring the submissive horse in or bring the dominant horse in depending on which is going to allow everybody to eat feed to get the nutrition that they need. Or you're going to have to live with some that are overweight and some that are a little on the thin side.

 

Katy Starr (14:08):

It's challenging. And so, talk to us a little bit more about the design of the study itself, how you had it set up and everything.

 

Dr. Karen Wimbush (14:16):

Sure, sure. So, we actually categorized the horses or put them into three major groups. Two of the groups were a mix of geldings and mares and the other one was an all mare group. Then we did it basically what we call a switchback experiment. So, in other words, every horse got every treatment and we decided that we were going to use feed troughs. So, they were, you know, typically about knee high feed troughs. And everybody had I think 1.2 meters. You know, they had, they had space at the feeder, so nobody was not be going to be able to get food or we fed them in individual pans that were spaced 20 meters apart. So, 20 meters is roughly 60 feet. So, they had plenty of extra room. And we simply said, okay, we did a randomization on who got pans first and who got troughs first.

 

Dr. Karen Wimbush (15:05):

And we took blood samples and heart rates on those horses before we even fed them. We fed them and then we allowed them to consume, I believe we were feeding alfalfa pellets. And I think one of your questions was why did we feed alfalfa pellets? We wanted something that they would want, but we also didn't want like a concentrate where one horse might end up eating too much and causing a health issue for that experimental horse. So, we decided that alfalfa pellets was a safe choice in case one horse ate twice as much as some of the other ones you wouldn't want to do, do that with grain and potentially cause a laminitic episode or whatever. So, we chose alfalfa pellets and then again we took blood samples and heart rates after they were finished eating. And then I think 30 minutes or so after they had finished everything. So, we had like three or four time points kind of before, right after. And then 30 or 60 minutes after they had finished their alfalfa pellets.

 

Katy Starr (16:11):

And how long did you do this for? Was this over like a couple weeks and you did a certain number of days? Or what was the duration like?

 

Dr. Karen Wimbush (16:19):

Actually it was just one time we did, everybody got tested, tested on pans and everybody got tested on troughs just at different times. So, one of the days I think we had available was October. Weobviously had to work around teaching schedules. So, in order to use all our horses, we had to do it during student breaks. So, one occurred during the fall break and one occurred on Veteran's Day, I think in November. So, they were roughly, I think a month or six weeks apart or so. Okay. So, we just did it one time, but we had, I think it was 16 head of horses. So, we had 16 data points for cortisol levels and heart rates for when they ate from individual pans. And then we had those data points for when they were fed on troughs while they were eating. While they were eating, we had two of us that were standing watching the whole thing marking all the behaviors that we saw, all the aggressive behaviors, the submissive behaviors, and then the neutral behaviors and things like that.

 

Dr. Karen Wimbush (17:18):

And so, we were basically checking off every time we saw a certain horse pin its ears or threaten to bite somebody or somebody felt pressure enough that they left, we called that displacement behavior. And so, we had all these behaviors that we were looking at. And so, when we were looking and eventually categorizing horses as either dominant, neutral or submissive animals, we used that categorization and we basically did a weighted score. So, if a horse pinned its ears, they might get one point for aggression. But if they actually followed through with, you know, mouth open bite, that would be a two or a three. And I forget the exact, you know, scores that we used, but obviously the horses that scored high in the aggression category, those were the dominant horses. And then horses that scored high in the submissive behaviors were obviously the submissive horses. And then we had that middle ground. And so, when we did the data analysis, we also looked at where those horses stood in their social hierarchy when we wanted to look at differences in cortisol, which of course is a stress hormone.

 

Katy Starr (18:25):

Right. You obviously, you studied the horses that were eating from either a shared trough or individual feed pans that were spread far apart. So, what stood out to you the most in terms of how those horses behaved differently between those two settings?

 

Dr. Karen Wimbush (18:41):

In the feed trough there were a lot more aggressive behaviors and there was a lot more displacement. And at some point I think some of the horses even just walked away and said, it's not worth trying to get to the feed trough. And you would kind of expect that and you're probably going to talk about, you know, some of our results. But probably the biggest take home was that cortisol level was, it was not different at all in the individually fed horses. So, the horses that were eating from individually fed space pans, their cortisol levels never really changed or anything like that. They were just pretty solid across the board. Everybody seemed to get along, which was very different than what we saw from the cortisol levels in the trough fed horses.

 

Katy Starr (19:23):

Right. Talk to us a little bit more then about that data collection process and how you measured the cortisol because with it being different from the trough fed horses versus the individual pans, what did that look like? Tell us a little bit more about those results and how they were impacted by the two different groups.

 

Dr. Karen Wimbush (19:44):

Sure. So, we elected not to put indwelling catheters in for this study just because that's a fairly invasive procedure. So, we just used a regular 20 gauge. It's a really small gauge needle. All our horses are pretty accustomed to needles and things like that because they're teaching horses so they have students practicing on them and things like that. So, nobody seemed overly alarmed. And with a small gauge needle like that, it's a pretty, most of the horses didn't even recognize that they were getting their blood sample taken. And then of course we did an enzyme linked immunoassay to measure cortisol and my colleague Dr. Bedore did that at Virginia Tech. So, we sent the samples away and she did that and we just simply got the results back. Surprisingly when we ran the statistics overall, I mean we had to say that there was no effect on cortisol when it comes to the feeder style, but we saw a lot of interactions.

 

Dr. Karen Wimbush (20:38):

And so, when we started to look at the interaction between feeder style and you know, that social hierarchy and those kinds of things, that's where we saw big differences. And I think the behavior data went along with that. We also found a couple of other, I guess, things that were not overly surprising. There was no difference in cortisol levels as an example between geldings and mares. So, we looked at to make sure that the horse's sex did not influence cortisol levels. What we did see, however, was cortisol levels significantly increased in December compared to October. And I think that when you look at the literature and things like that, cortisol is a stress hormone that changes some of the metabolic processes in horses. And so, normally in most horses, cortisol level does increase going into the winter months because it kind of gets that animal's physiology ready for adapting to a more stressful environment. So, that was, I guess not really unexpected when we looked at it and compared it to what the literature was. What was probably most interesting was that before we ever started, the dominant horses had elevated cortisol because I think that they were already stressing the fact that they were going to have to guard or become possessive. 

 

Katy Starr (22:00):

That anticipation almost...

 

Dr. Karen Wimbush (22:00):

Right. Anticipation and the resources, I think that we see that in some of the other things as far as horses going into performance activities where their cortisol and their heart rate goes up because they're anticipating the activity. They haven't done it yet, but they're anticipating that they're going to do it. Just from a rider standpoint, the horse is already anticipating, let's say you going into your show ring now you add into the picture that the rider's heart rate is also increased because they're anticipating going into the show ring. And then you wonder why your horse acts like they do in the show ring compared to what they do at home. It's all connected. Horses are extremely sensitive when it comes to that and they're perceptive when it comes to that. So, those horses already knew probably just the fact that they were seeing feed troughs that something was going to happen even though it was not done. The tests were not done at the normal feeding time because we were feeding a forage pellet alfalfa pellets, but they had high cortisol's and that was in the dominant horses and the neutral horses, less so in the submissive horses. Cortisol actually was highest before they ever ate.

 

Katy Starr (23:12):

Yeah, that is interesting. But it makes a lot of sense, especially when you do own multiple horses. Because that's one thing that I always like to do is sometimes just observe their behaviors and mannerisms and how they interact with each other in different situations. And so, it makes a lot of sense when you see that research actually kind of come into play. And on the submissive horses though, you found that they did kind of stay consistently stressed when using the shared trough. Is that something that owners should be concerned about long term or what are your thoughts with that?

 

Dr. Karen Wimbush (23:45):

That's a really good question, Katy, because, how do I want to say this? Today everybody seems to be so concerned about horse welfare and I'm not saying that they shouldn't be, but I think our perceptions are very different than the horse's perceptions on what is welfare. Acute stress is part of life and you and I both know it. I would say I was probably a little stressed actually coming on this podcast because this is my first podcast. Is that a good thing? I think solid individuals, whether it's people, whether it's dogs, whether it's horses, they can adapt to acute stresses. In fact, I think that that's a good thing. I think being able to adapt to stresses actually makes an animal more trainable because they can go into that new situation, that novel situation or whatever and they can adjust and realize and learn from it.

 

Dr. Karen Wimbush (24:43):

I think individuals that, and I'm not going to talk about humans, but if a dog, let's say, because I'm also into canine behavior quite a bit, if a dog doesn't have the genetics, you know yeah there's a genetic component to behavior without a doubt or they've had an upbringing that has not been stable, those dogs may never really learn to adapt to stress and they may develop stereotypies or behaviors that are really self-destructing. Okay. Or, or whatever. And so, I think that acute stress is fine. Certainly chronic stress. However we know, and we've known for years depresses the immune system. I think Bruce Nock who is founder of the Liberated Horsemanship movement, he's a PhD, I think human physiologist, I mean he's very well educated and he really made some good observations that horses that were chronically stressed seemed to be more prone to laminitic bouts and things like that.

 

Dr. Karen Wimbush (25:46):

So, not just immune systems but also you know, laminitis. And you know, I would venture to say even changes in the gut microbiome, which of course now is one of those big key research areas. So, I'm not going to speak to that because I don't know anything. But I would imagine that chronic stress affects a lot of just probably a lot of body systems. And so, that becomes an issue. And so, I think that submissive horse that's always worried about, did I look at the wrong horse? I really am hungry, but I really don't want to go up there and eat. I think that can lead to some serious health problems long term. And so, from a horse owner standpoint, I think it's not the acute stress, it's not that when you introduce a new horse, it's not the dominant mare chasing them around the pasture for a time or two and then they settle things. I think it's that chronic stress that is the health problem.

 

Katy Starr (26:44):

Yeah, that makes a lot of sense. And one thing actually, I remember what I was going to ask you from our earlier conversation, but when you were talking about how you were kind of making observations on their behaviors, was there a standard, is there like a set standard for like a rubric of some sort that you guys use to be able to identify those different behavior tendencies?

 

Dr. Karen Wimbush (27:10):

Sure. We came up ahead of time with a rubric. And so, we basically, each of us that were neutral observers, my colleague was observing separately from me and we were just had clipboards. And so, we were documenting every horse, of course we could identify them visually because we knew who was who. So, that wasn't a huge issue. And we could document. And so, we had a list of all the behaviors we were going to look at ahead of time. And then we just had to put tally marks by which horse did what, when, and then each of us, we compared it and then I believe we took the averages. So, for the most part our observations were pretty consistent. There might have been one ear pinning that my colleague saw that I didn't or whatever. But basically then we just averaged our observations.

 

Katy Starr (27:53):

Okay. Yep. That makes sense. And obviously through this research, it kind of, which not necessarily surprisingly, but it did show that feeder spacing within group dynamics versus using individual pans and things like that does have an impact on their stress levels. So, through this research, what would you say is one big takeaway that you think that every horse owner should know from this?

 

Dr. Karen Wimbush (28:21):

Sure. I think everything's a trade off. Dumping feed in a trough is way easier. And especially if you've got an aggressive group of horses and you and I probably have been there where we're feeding aggressive horses. If your trough is up against a fence or someplace like that, or you're driving your UTV through, it's safer for the humans without a doubt to just dump it and go. It's a lot more dangerous from a human standpoint if you're feeding a fairly aggressive group to go around to individual pans and feed them. But I think from a horse's standpoint, without a doubt, I would prefer to feed them in individual pans. Again, this is fairly common sense, but I remember way back, I had some background in pony club and that kind of thing. It was like we would always have one extra pan. It was a little bit like the opposite of musical chairs.

 

Dr. Karen Wimbush (29:08):

If you had 10 horses, you had 11 pans so that if somebody got displaced they still were going to get something. Now granted your dominant horses might get two pans, but again, you thought that through. I think that there are some other feeding systems that I think are great. They obviously cost a lot of money. I think some of the bigger farms, particularly the breeding farms, they'll actually have standing stalls in pastures. So, the horses learn to come up into their individual stalls and then you can basically just close them in for the 15 minutes that they're going to be there, feed them their individual rations and leave. But that usually takes, you're going to have to think that through and you're going to have to have the right facility. Because you're probably going to have to have a concrete pad. You're going to have to build at least an open shed with a roof on it or whatever, an open structure. And you're going to have to have those individual stalls and those horses are going to have to learn to go in there. But you know, horses are again adaptable. I have eight dogs, so you know, everybody learns what crate they go in to get their meal twice a day. And it's good. Everybody's like, I go into my crate and my crate only and this is where I eat. And so, I think that that's an option, but it's not a cheap option because you're going to have to build a whole other structure.

 

Katy Starr (30:22):

That just kind of takes what we are learning through all this. Right. And everybody realizing that here's the information that we have and what we've learned about how the animals interact with each other. You know, during feeding times and things like that. And so, we could always say, in an ideal world, do this, this, and this. But not everybody has that ideal world. And especially with the different personalities of horses and everything, you kind of just need to take what you have in your situation and do your best with what you have and the time that you have too, because that's another thing is sometimes time is a constraint as well. And so, between time and money, I guess those are the two biggest things when it comes to owning horses and other livestock and things like that. But if you had a chance to start this study over again, is there anything that you would do differently? Or is there anything that you would want to do off of this study? Something that you learned that you're like, this brought up another question and I'd love to get this answered if we had the opportunity to further the research.

 

Dr. Karen Wimbush (31:28):

Sure. I think we always say we would like to repeat it and have more trials to make sure that it's truly consistent, that we're getting consistent results. But the other piece of this is, my first question is, are dominant horses stressed all the time? And so, I would love to have solid groups of horses that you knew who the dominant was and actually just do fecal cortisol. So, be able to pick up manure or do hair cortisols or something like that. Are dominant horses more stressed than neutral and submissive horses? Because I think we always look at the submissive horse as being the one that's picked on in everything. But I think being a leader in the animal world is kind of stressful.I remember we had a rescue Aussie, and he came in as an adult and he had been an only dog for a while and he came into my pack and he basically became leader very, very quickly.

 

Dr. Karen Wimbush (32:29):

And what was really funny is throughout years this dog never played, he never played with toys, he never played with anything. He was just always the boss. And then dynamics changed. A couple dogs beat up on him and he fell from the top dog position and all of a sudden, he started playing, which I had never seen him play before. But he fell from being the top dog to being kind of in the middle of the group. And his outlook on life, his behaviors seemed to indicate that he was now allowed to do behaviors that I don't think he did before. I just always wonder whether we always think about the submissive animals as being, oh, the poor horse down at the bottom, but how stressful is it to be the leader of a group?

 

Katy Starr (33:18):

When you think about that, even like in the human sense when it comes to like running businesses and things like that and the stress level that's associated with it, they feel like they always have to be in control and overworked. And so, that dominant mentality makes a lot of sense. But that would be very interesting to learn more about and just to see where the research takes you on something like that.

 

Dr. Karen Wimbush (33:45):

Right. And you would need multiple solid, consistent groups to do multiple fecal checks throughout the year and that kind of thing. And you'd need a big number because it's like you'd want 25 dominant horses, you would want a hundred in the middle, you would want 25 at the bottom. And it's like, where do these cortisol levels fall? And I think you're right. I think we tend to overlook that. But yes, in humans, like you said, the person that's running the show is always stressed. The person that's a little bit worried about losing their job is stressed. And the less stressful people are in the middle going, my job is secure, but I can go home at five o'clock and not come in on weekends .

 

Katy Starr (34:26):

And not bring my work home.

 

Dr. Karen Wimbush (34:28):

Exactly. And have that life work balance. And so, I think that trying to figure out that situation in animal groups is kind of fascinating.

 

Katy Starr (34:38):

Yeah, that's so interesting. Well, and as we kind of start going towards the end of our chat today, there was a couple other things that we wanted to talk a little bit about because it involves some of the other research that you have been a part of with stress and things like that. And so, one of the other pieces that you had worked on was the effects of pen size on stress responses of stall housed horses receiving one hour of daily turnout. Can you talk about that just a little bit and why you guys wanted to do that study?

 

Dr. Karen Wimbush (35:12):

Sure. I think it comes back to growing up on a 50 acre farm where my horses had 30 acres to roam on. I mean all three horses and they have 30 acres, you know, they have woods, they have streams. And you look at the stalled horses, the horses that are boarded and everybody's like, oh, he gets an hour turnout and you're sitting and going, he's turned out in a dry lot. That horse can't run. It can't play. There's just so many things it can't do. It might get social interaction during that turnout, but it really can't do the things that horses, I think in the wild would do. And I use that word to mean feral horses. And so, we wanted to look at what's the inadequate pen size if you're going to turn out a group of horses. And I think we were using four horses in that study.

 

Dr. Karen Wimbush (35:56):

And what we did is I think we took every horse and we looked at and calculated their natural flight zone. So, we had them in the middle eating some hay in the middle of a big outdoor arena. And we just proceeded to walk a horse towards that horse. And when that horse that was eating noticed that another horse was encroaching on his space, it might've been an ear flick, it might've been looking, it might've been stop chewing. But as soon as that horse noticed that that second horse was approaching, we called that the flight zone. And so, basically we looked and our large pen, our large turnout pen allowed every horse to have its flight zone. So, we took all the flight zones, we averaged them, and we said this is the average flight zone for this group of horses. Okay. And so, the large pen had everybody could have their own space and be out of each other's flight zones.

 

Dr. Karen Wimbush (36:53):

And then we had the small pen, which we actually use the per animal allocated space based on what we call the IACUC, the animal care and use guidelines, which was basically not real big. And then I think for the middle group, we took the average flight zone space minus one standard deviation or one variance step. And so, that was our medium group and we definitely saw differences. So, there was a lot more displacement and a lot more, I guess, you know, interaction from a kind of dominant, aggressive manner in the horses that were in the small pens. But interestingly enough, we never saw rolling behavior, laying down behavior until they were in the large pen. So, horses would roll, horses would lay down in that large pen that they would not do in the medium sized or the small pen. So, and that again makes sense because if I'm worried about somebody coming in and into my flight zone, then I wouldn't want to put myself in a submissive position.

 

Katy Starr (38:07):

Yeah, got to be ready .

 

Dr. Karen Wimbush (38:08):

Yes, exactly. I have to be ready to move whatever. And we saw more sharing of hay in the large pen. So, when horses felt like they could walk up to the hay and yet be able to get away if they needed to, we saw more of that in the large pen as well. That was kind of some interesting research as well that we did from a group interaction standpoint.

 

Katy Starr (38:29):

And something that's very interesting to me about this is my perspective a lot of the time, obviously just because I think my role in what I do here with Standlee and everything is thinking about the perspective of horses being out on pasture. And if you're feeding them, how much pasture do you need to be able to feed them without having to supplement them with extra hay or hay alternatives or concentrate or anything like that. And so, for me, this was very interesting because I never really thought about it from that perspective of horse may not be able to have pasture, but giving them turnout. Right. Well how much turnout? Because in my mind, you know, I'm always thinking about how much do they need to be able to fill their nutritional needs. And so, from those that have that situation where they just have like a dry lot or something like that, that's not really what that's for. Right. But how much space do they need? And so, being able to determine what those flight zones were and seeing that it did make a difference in their behavior, their specific behaviors, especially those where they wouldn't roll or something like that, that made them maybe a little bit more vulnerable. I found that to be really interesting with that research that you shared about that you did the behavior observations and then also cortisol testing as well?

 

Dr. Karen Wimbush (39:44):

Yes. Again, a lot of research when you do it and you just ask in the analysis for what are the major effects, we didn't see any overall effects between the pen size and cortisol. But when you start to look at time points within that, we call them interaction effects. And so, we saw lower cortisol levels at certain time points in the large pen. And so, that definitely indicates that it's going to be more stressful when those horses are turned out in a small pen than when they each have their individual space. And again, people all have spaces too. I always joke around, I'm like, my flight zone's pretty big. Yeah. Like, don't get me.

 

Katy Starr (40:26):

We call them our bubbles. Right?

 

Dr. Karen Wimbush (40:28):

Yes. My bubble is big, and I don't like cities. I much rather be out hiking or doing whatever. Because I have a large bubble. And so, I think horses are like that too, for sure. Yeah.

 

Katy Starr (40:39):

Yeah. That's interesting. And then the other thing that you brought up to me when we were kind of chatting about this conversation, you were talking a little bit about the acclimation reduces stress in adult horses, tied in visual isolation. Talk just a little bit about that study and what you were doing there with that one.

 

Dr. Karen Wimbush (40:59):

Sure, well we were looking at novel stresses and adaptations because again, some of the animal rights, people seem to think that horses and any animal, they don't adjust well. They don't adapt well. And so, one of the things we wanted to look at was how long does it take to acclimate horses to a novel stressor? So, horses don't want to be tied out by themselves where they can't see other horses. And by the way, we did some before this even, and I, and you and I haven't even talked about this, I did a research study that we were looking at the effects of horses being tied with over checks. And we have the biggest Amish population here in Ohio, probably of any place in the world. So, we go to local Walmarts and everything like that. And we see horses tied up. They're harnessed and bugged. And so, one of the things was, I noticed that some horses were tied for a long period of time with a high over check, meaning that their head was kind of fixed high.

 

Dr. Karen Wimbush (41:52):

And then other times you would have horses that did not have their over checks on or they would have low over checks. And we did see that horses, we tested stress levels in horses that were not tied with over checks. Horses with low over checks, horses with high over checks. And we saw that horses with high over checks were much more likely to have high cortisol levels and they were also more likely to be muscle sore and tight the following day. That kind of led in. The interesting thing about that study is it wasn't dependent on the over check, just having horses tied up standing in one position for 90 minutes. It was just basically tied up. Like people would tie up their horse and walk away. They were more sore in their muscles and they had tighter muscles 24 hours later. So, just standing still for 90 minutes had a physical effect on these horses.

 

Dr. Karen Wimbush (42:43):

Okay. And so, that kind of led to, well, should we be tying horses and walking away? And so, we basically decided to acclimate horses or not acclimate horses. So, we took two groups and we said, we're going to test you guys, we're going to tie you individually where you couldn't see other horses. And so, we tied up everybody and this took multiple time trials because I forget how many, I think we did 12 horses or something. And we had four tie stations that they could hear each other, but they couldn't see each other. And so, we tied everybody, you know, did cortisols before and after the 60 minute tie. And everybody was super high the first go around. We acclimated half the horses. So, we tied them every day, five days a week for two weeks. And we came back and we did the trial again - well everybody was acclimated. Just one tie time being tied by themselves without being able to see horses for 60 minutes acclimated the horses. So, it was kind of a bust. We never got a journal article out of it. I presented it as an abstract because basically everybody got acclimated in that first hour. Everybody was like, okay, I give in, this is where I'm at. Yeah.

 

Katy Starr (43:56):

And they're fine with it. Yeah.

 

Dr. Karen Wimbush (43:57):

And so, I think an animal's ability to adapt to a novel stressor is a lot shorter than we want to think. You know, they adapted just quite fine. And so, like I said, we basically were like everybody's cortisol was higher first go around, nobody's cortisol was higher the second go around. Yeah. I think that that's a take home message too, that when horses are given the opportunity to adapt to a novel situation, they actually do a pretty good job of it.

 

Katy Starr (44:23):

Yeah. Just give them the opportunity to. Yeah. That's really interesting. And I think it's helpful to help us understand. Because I think we are really quick to, and I don't know if it's so much the folks that are very hands-on involved with animals as much as it is folks that aren't, but just giving like human feelings or whatever you want to call it to animals, but just realizing that they may be more capable of certain things than we give them credit for. But even this research, like you say, you weren't able to get a paper out of it because of what you figured out, but you answered something. I feel like that's kind of important. You thought you might get more out of it. But that just shows I think how important it's to kind of have this understanding of how we care for our horses and manage our horses and yeah. I think that was really interesting. As we kind of start to wrap this episode up, what would you say are your key takeaways that you would like to leave listeners with? If they have multiple horses that they're having to feed and care for?

 

Dr. Karen Wimbush (45:28):

Right. I think if you can feed them spaced apart and it's safe for you as a owner to do that, I think that that's probably a better practice than trough feeding. But the other piece of this whole thing is, as we kind of put together a lot of the pieces of the research that I've done over the years is that acute stress is not the same as chronic stress. That horses are very adaptable to stress and or I should say, changes in their environment or novel situations. Just like you mentioned, it's like it's not the horse people that think badly of horses in unusual situations. It's usually the bystanders, the onlookers, the citizens that are concerned about animal welfare.

 

Katy Starr (46:10):

Right.

 

Dr. Karen Wimbush (46:11):

But maybe don't really understand horses. Even things like wearing blankets, we tend to go, oh, the horse needs a blanket because I need a coat. Yeah. But the horses have have, they have a winter coat, it's grown on them. And so, I think the most important thing is don't put your human perceptions and projections on animals because they're probably a lot more adapted to their environment than we want to give them credit for. So, I think that that's probably one of the biggest take home messages overall is that they are adaptable and they can have acute stressors in their life, get over it and not have any overall health concerns.

 

Katy Starr (46:54):

Right. Excellent. Well, Dr. Wimbush, thank you. How could our listeners stay connected with you after this episode?

 

Dr. Karen Wimbush (47:02):

Sure. They're welcome to send me an email. It's wimbush.4@osu.edu.

 

Katy Starr (47:12):

Excellent. I'll be sure to put that in our show notes in case anybody wants to reach out to you to ask any other questions about some of the research that you've done. Thank you so much for being on with us today. I can't thank you enough for giving us your time and we appreciate you being here.

 

Dr. Karen Wimbush (47:27):

Well, thank you. Because I think now my cortisol levels a little lower now. So,

 

Katy Starr (47:33):

It's finally,

 

Dr. Karen Wimbush (47:34):

That short term stressor, which is like, okay, I learned from this situation and the podcast was not nearly as scary or intimidating as I thought it might be. .

 

Katy Starr (47:45):

Well, we thank you for being on your first podcast with us. It was great to hear from you and some of the research that you've done. Thanks for your time today.

 

Dr. Karen Wimbush (47:53):

Great. Thank you Katy.

 

Katy Starr (47:56):

Thanks for listening to the Beyond the Barn podcast by Standlee Forage. We'd love for you to share our podcast with your favorite people and subscribe on Apple, Spotify, or your favorite listening platform. Until next time, keep your cinch tight and don't forget to turn off the water.