Dr. Caroline Mansfield, registered specialist in internal medicine and honorary research professorial fellow at the University of Queensland and clinician at James Cook University, joins Dr. Andy Roark to discuss the role of the gut microbiome in the health and disease of dogs and cats. Caroline provides an overview of the importance of the microbiome in general pet health, the impact of antimicrobials, and her thoughts on what future research in this area might find.
This episode is made possible by Purina Institute!
ABOUT OUR GUEST
Professor Caroline Mansfield is a registered specialist in small animal medicine and is recognised as an international leader in veterinary internal medicine, as evidenced by frequent invitations to present at international conferences, requests to provide expert opinions and current and previous roles in the profession. She is a past Board member and President of the Australian and New Zealand College of Veterinary Scientists and has been a member of the Board of Examiners for the National Veterinary Examination. Her expertise is recognized outside of the sphere of clinical veterinary medicine by participating in the peer review process for Australian Research Council Discovery Early Career Researcher awards (DECRA) and Discovery projects from 2015 to present. She is currently Chief Editor for the Australian Veterinary Practitioner, on the Editorial Board for Animals, a member of the Purina Institute advisory group and received the 2019 Award for Scientific Excellence from the Australian Small Animal Veterinarians. She is currently an honorary research professorial fellow at the University of Queensland and clinician at James Cook University, located in tropical far north Queensland. Her research is focused on the interaction of the gut microbiome in the health and disease of dogs and cats, and the role diet and environment play in this. She also researches in areas of clinical gastroenterology that can result in tangible improvement in the health and welfare of our pets. She has published over 90 peer-reviewed papers plus multiple textbook chapters and conference presentations. To date, she has supervised over 30 post-graduate students and clinical residents to successful completion.
Dr. Andy Roark (00:07):
Hello and welcome everybody to the Cone of Shame Veterinary Podcast. I am your host, Dr. Andy Roark. Guys, I got a great one today. I am here with Dr. Caroline Mansfield. She does a lot of things that I will talk to you about when she comes onto the podcast, but her main emphasis is in research on the interaction of the gut microbiome in health and disease in dogs and cats. And so I think she’s fascinating. I think gut microbiome research is fascinating. I am really amazed and odd as you will hear about what we are learning about gut health and how gut health interacts with health in the rest of the bodies and how basically every organ system can be tied back in some way, shape or form, probably to the microbiome and into gut health. And so anyway, we start talking about cognitive dysfunction and the role that the microbiome plays in that we start talking about where prevention and treatment of a variety of the illnesses might go in the future and what research in gut microbiome looks like in that.
If you just don’t know much about sort of the gut microbiome research and why people are talking about it and why it’s becoming a big deal in nutrition in general animal health, this is a great episode. I talked to her a little bit about the wellness industry and about the noise that’s generally around nutrition and things like this and how to kind of separate out what is worth talking about and what is not, and try to get our head straight so that we can be a valuable resource when we talk to pet owners. So anyway, it is a sprawling conversation about a topic that I think is incredible, and so you’ll hear my wonder and excitement when you get into this episode. I hope you’ll like it a lot. I have been thinking a lot about this episode since we did it. Anyway, that’s enough. Let’s get into this episode with Dr. Caroline Mansfield. Also, I got to say thanks to Purina Institute, they are making this episode possible ad free for you guys, and so shout out to them. Let’s get into it.
Kelsey Beth Carpenter (02:01):
(singing) This is your show. We’re glad you’re here. We want to help you in your veterinary career. Welcome to the Cone of Shame with Dr. Andy Roark.
Dr. Andy Roark (02:17):
Welcome to the podcast, Dr. Caroline Mansfield. Thank you for being here.
Dr. Caroline Mansfield (02:22):
Oh, thank you. You’re welcome.
Dr. Andy Roark (02:23):
Oh, it is a pleasure to have you here. You had to get up really early for this podcast. I really appreciate it. You are. For those who don’t know, a registered specialist in internal medicine, you are a past board member and president of the Australian and New Zealand College of Veterinary Specialists. You are the chief editor for the Australian Veterinary Practitioner. I could just keep going and going have, but you have over 90 peer reviewed publications. My wife is a college professor. I don’t know if people know how amazing that is, that incredible amount of work. You have supervised over 30 graduate students. You have done absolutely incredible things. And so I really just, I appreciate making time to be here. I want to talk with you about nutrition and there was something I was really sort laxing philosophical about as I was sort of preparing for our time together and I was thinking about having you come on and stuff like that.
And so I’ve got this idea that we do not look at life and especially at medicine with the wonder that it deserves. And so I look around at our world and just simple concepts like our physiology, our immune system. It is absolutely astonishing that we have this system that works as well as it does. And I just think about so much of what we do in medicine and we just take it as, oh yeah, well, we have this and we know that and we know that the body works this way in that way, but I really don’t think that we just look at life with the wonder that it deserves. And so your research really focuses on the interaction of the gut microbiome in health and disease in dogs and cats. And so I’m thinking about this idea that the gut microbiome has this role that is so large and sort of ubiquitous through our body and through health in dogs and cats, but also in humans. And I don’t know that people really process what that means. And so let me just sort of open up here at just a high level paint for me sort a picture of how you look at the gut microbiome and its role in healthcare in general, if you don’t mind.
Dr. Caroline Mansfield (04:38):
Sure. I guess it’s kind of interesting that you talk about that wonder and that excitement about medicine and physiology. I feel super excited every time I learn something new about the microbiome or the way that it interacts with the body. I think it’s incredibly fascinating area. It’s probably like having a whole other organism within an organism. So it has an interaction with virtually every organ system is affected by the gut. And the gut is from an immune perspective, is probably one of the most important interfaces with the environment. The gut is usually where we are exposed to multiple antigens on a daily basis. So the gut microbiome influences that immunity, that immune system. It influences the way the brain develops as a child or as a puppy or a kitten influences behavior. It influences kidney disease, influences development of uroliths. It’s fascinating all of the interactions that it potentially has.
And probably what’s even more fascinating is that we didn’t understand how much was there because we didn’t have the technology to identify all of the organisms that were in the gut microbiome until recently. And even now, I still think we’re a little bit limited in how we understand or basic in how we understand because I think each bacteria has the capacity to have different functions. And so there’s this kind of redundancy or fail safe system. So it’s not enough just to know what bacteria are there, it’s what they’re doing, whether they have their buddies there to help them or not. It’s justs just super fascinating.
Dr. Andy Roark (06:35):
I completely agree, and I appreciate you saying that this is fairly new in coming to light because it does feel fairly new. We didn’t have this sort of insight when I was in veterinary school. And so I’m seeing this sort of research coming out and I, I’m trying to get my sort of hands around it and I’m thinking about it in a lot of different ways. So first it’s just my basic understanding of the physiology and how this affects my patients. But then also we start to get into therapeutics. We start talking about wellness care, and then we also start talking about addressing disease states. If you’re talking to, I don’t know, just say a doctor who didn’t have a robust understanding of this coming out of vet school and has been sort of trying to catch up, how do you help veterinarians, veterinary technicians, nurses, how do you help them think about this microbiome just at a systemic level if they say to you, this is all really new to me and I’m trying to get my head around it so I can start to understand and start to talk in a way that’s helpful for my patients.
Where do you start?
Dr. Caroline Mansfield (07:31):
I guess, I don’t know. Well, it’s a little bit lyrical. I sort of talk about the fact that the microbiome, it’s not equally divided. It’s not good or bad, but to have a really healthy community, just like a healthy human community, you need diversity and you need the bacteria or the participants in that community are doing different functions and they’re all contributing together to work towards a particular goal. So I guess the things that we need to be thinking about is that when we talking about nutrition, we can talk about basic nutritional requirements like protein and carbohydrates and fat and so on, but we also need to be aware that any diet that we feed affects that community. And so if we want to enhance a particular function, I’m really loathed to talk too much about particular bacterial species because I think I was alluding to before, particular bacterial strains or species will only be effective if other bacterial strains are present.
And they do have a redundancy in their roles. And so I think it’s better to think about the functionality. And so most diets provide some kind of prebiotics, which it’s kind of like a fertilizer, I guess, to promote growth and diversity of that microbiome. And we also have the capacity to influence it positively by using prebiotics or what post-biotics, which are probably the new emerging fields. So those are the metabolites that bacteria produce, but we also have the capacity to do it a lot of harm. So I think particularly with the use of antimicrobials indiscriminately, we often think, well, we’re treating that urinary tract infection or we’re treating that ear infection or pyoderma, but we’re not doing absolutely no harm to the animal and the animal’s microbiome when we use those antimicrobials,
Dr. Andy Roark (09:45):
When we disrupt that way, when we use systemic antibiotics for cystitis or for, that’s the classic one, is we better safe than sorry. And so we use antibiotics when we have cystitis or even a pyoderma that we could maybe treat topically and we don’t. Talk to me a little bit about the recovery period. How does that manifest clinically? What does the fallout that we see?
Dr. Caroline Mansfield (10:10):
So I think that’s a really good question, and I wish there was a really simple answer, but there’s probably not because each individual microbiome is going to respond really quite differently. And even within an individual there, microbiome might respond differently at different times. I use the analogy of an elastic band. And so if you’ve got a really healthy, fresh, new elastic band and you stretch it, so you give it se antimicrobial, so you disrupt it, you give it for a short period of time and then you release it, the elastic band’s going to go back to normal pretty quickly. But the more that you stretch it, or if it’s an old elastic band or it’s a little bit sick when you stretch it, it just doesn’t go back as normal the next time. So it is highly individualized, and I think we probably don’t, A lot of the analysis that’s been done, a lot of the studies that have been done, the way that the microbiome has assessed probably doesn’t completely answer that question because it doesn’t completely answer the functional capacity. But we know that, for example, metronidazole has impacts for a very long time. We’re talking weeks to months after it’s been discontinued, but again, it’s really highly individual. Some animals will revert back to normal more quickly and some will take longer.
Dr. Andy Roark (11:30):
I think about sort of looking at diets this way and sort of processing what the microbiome means to overall animal health. And we’ve already got people, we’ve had pet owners for decades now who have been very attuned to what their pets are eating. They are very interested in the nutrition and what they feed their pets. It’s something that pet owners can see. They have a feeling of control about what they feed. I can also see this being an area for a lot of confusion. I can see a lot of people trying to do what’s best for their pets and kind of heading off in a sort of misguided directions. Let’s start to take this focus on the microbiome into a more sort of practical clinical conversation. How do we start to advise pet owners on diet selection and what’s important and what are sort of the pitfalls that we might fall in or areas where we might see pet owners kind of going off in a way that’s not productive?
Dr. Caroline Mansfield (12:26):
Yeah, I guess part of the problem with, part of the problem with the microbiome or it’s I guess the downside for its increasing popularity is that there’s a lot of increasing noise around about it and a lot of noise about how to manipulate it. And that kind of corresponds with, I guess that sort of whole wellness industry that I think is being translated into the veterinary pet owners. They take themselves very seriously. I think we have, the advantage with pet food though is that we can control what they eat to a certain degree. And I think as long as it’s a well-balanced diet, I mean it’s been proven and the dog is healthy or the cat is healthy, there’s probably not a lot of benefit in manipulating the microbiome in those animals. So the times, I guess when we start to think about it are once they’ve actually developed disease and particularly gut disease, that’s probably more when we know that manipulating the microbiome is likely to be effective. And also there’s some emerging things that are happening like with cognitive dysfunction in dogs and epilepsy and manipulating the microbiome in those may be beneficial. And I guess also when we think about it with some conditions like hepatic encephalopathy or liver failure, we’ve been manipulating the microbiome for half a century with lactulose, but we didn’t really aware that’s why we were doing it. So I don’t know that I’ve actually answered your question very well though.
Dr. Andy Roark (14:09):
No, no, I think you did. I knew exactly where I was going is the wellness industry is definitely spilling over into pet health, and this is when we start talking about gut microbiome. I hear this in the wellness industry all the time of people talking about protecting yourself against Alzheimer’s, people getting joint health from the supplements that we take and things like that. And there are supplements that are hugely valuable and wonderful, and there’s a lot that’s not. But I think you put your finger right on it. When I said I anticipate the noise of this, I hear a lot, and I don’t mean to start a controversy about this, but there’s a lot of people who put forward raw foods or things like that specifically because they say, oh, the microbiome is important and this is a more robust way to increase diversity in the microbiome and things like that.
And again, I’m not trying to start the raw food, not raw food debate at all, but there are a lot of people who have strong opinions. And so I think I just want to be, I appreciate you answering in sort of an even-handed way. Really what I was looking for is I want to have productive conversations about this and not just jump to conclusions or overstate what is available and what patterns need to look for in their food. So I think you asked it well, are there, the second part of my question was really how does this go off the rails? Are there areas of misunderstanding that you see where either doctors or pet owners, I don’t know, they take part truths or they have common misunderstandings or things that kind of derail these conversations?
Dr. Caroline Mansfield (15:50):
I think personally and probably in my experience not so much. I mean, I think I’m privileged that I work in a referral population. So normally the people are coming to me for advice, and so usually are quite happy to take advice. It’s interesting that there are some people that are very resistant to some diet regimes, but when you start talking about manipulating the microbiome and that there are other ways to do that, so we can use prebiotics, we can use fiber, we can use, probably not so much postbiotics anymore at this stage. They’re not really developed, but we can use probiotics to a certain extent. I find that people are really quite willing to take that on board. They’re probably not, if they’re very set in their ideas about what they want to feed their animal. And I do come across those people. They have really strong beliefs. I tend not to try and work against them. I tend to try and work with them and just to make sure that the diet is appropriate for the animal if it’s not what else they need to have to make that appropriate or if we can help in any way. But I tend to find if I’ll alienate them if I tell them that I disagree with ’em or I think that their diet choice is wrong and then you lose them.
Dr. Andy Roark (17:21):
Right, yeah.I think we’ve all kind had to do that math at some point and to say, is this the hill I want to die on, or do I want to continue on so that that’s right. We can work on the future. Yeah,
Dr. Caroline Mansfield (17:32):
Pick your battles.
Dr. Andy Roark (17:34):
Yeah, definitely. Talk to me a little bit about where you see this field going. I got to tell you, going back to the statement of wonder I had at the beginning, when we start talking about the microbiome and its impacts on cognitive dysfunction, that’s magical to me. That is so beyond what we ever used to think. And the idea that there’s something we can do for cognitive decline or things like that is amazing. Where do you see this sort of research going? How do you see the science here manifesting out into healthcare into actually treating dogs and cats in the future? What’s this going to look like?
Dr. Caroline Mansfield (18:17):
So what I’d love it to look like, so there’s a few things in the human field. So there’s something that was called the American Gut Project. It’s a bit of a misnomer because they do get samples from around the world, but where they’re basically screening people and looking for, I guess if there’s geographical differences, seasonal differences and so on. And we don’t really know that that well in dogs yet, partly because of the costs of sequencing. So a lot of it has been done with the method called 16S, which takes the ribosomal RNA gene that’s ubiquitous in bacteria, and then it amplifies that, and then you get your sequencing data, but it does miss a lot of stuff. It doesn’t go down to a species level, and there’s just a lot of noise that surrounds 16S. So using different methodologies is really expensive.
It’s coming down in price now, so it’s probably more useful, but it’s still expensive. So where I would love to see it is I’d love to see similar situations in veterinary medicine where we’re actually tracking it. We track cohorts of animals across the world, different breeds, and we then are able to also track their health. And so we can actually see whether there’s a preceding marker or a flag or a change in the microbiome that actually precedes the development of any clinical disease. And to me, that’s where the magic would really happen. So if we could have it as part of our health check and we go, well, hang on, we’re seeing this shift in the microbiome, and that suggests to me that if we can intervene here, we may prolong or prevent the development of this particular disease. That’s where I think the real magic is going to come. But that’s a long way away because we need to be tracking these animals and we need to be doing all of those and correlating them to the diseases. But you talked about cognitive dysfunction. One of the cognitive dysfunction can’t talk properly. I’m getting too excited. One of the really interesting things with Alzheimer’s disease is they have actually shown that changes in the microbiome proceed any detectable change by one to two years in people. So I know like, wow, isn’t that amazing?
Dr. Andy Roark (20:49):
Well, think about, I mean, that is amazing. One of the things that we have going for us in veterinary medicine is our patient’s lifespan are much shorter, which is bad, but the beautiful part is starting to gain that type of whole lifespan knowledge. We can do it much faster than if you were following cohorts of people that started in their twenties and age into their eighties and nineties. So anyway, this is super exciting. If people want to learn more, do you have favorite resources? Are there places that you would send veterinarians, nurses, even engaged pet owners? What do you like for general educational growth in this topic?
Dr. Caroline Mansfield (21:29):
Yeah, so the problem is that there is so much information coming out. So if you put microbiome in, you’ll have 25,000 hits. So sometimes I think there’s almost, there is almost too much information. I do find the Purina Institute Center Square, they’ve got a lot of really good resources. They’ve recently had a microbiome forum, which I think it may still be available online and the recording, which don’t quote me on that. So I think that breaks it down and it also breaks it down quite nicely into bite-sized pieces that are good for speaking to clients about particular conditions as well. So I think those resources are really good for more general nutrition. I think the WSAVA, the World Small Animal Veterinary Association has some amazing resources. So nutritional toolkits and diet history forms. They also run some modules on nutrition, which are free, which I think are really useful for techs and new grads to do as well. And then I guess it kind of depends on what condition you’re talking about, then you kind of go more specific websites. But I think those are probably good places to start.
Dr. Andy Roark (22:55):
I love that. I’ll put links to the Purinas Institute Center Square in the show notes. If the Microbiome Forum is still up, I’ll link to that as well in the notes. And then the WSAVA, I’ll definitely link to that. And their nutrition toolkits are excellent and their nutrition modules as well. So I’ll put links to all that stuff. Caroline, thank you so much for being here. I thoroughly enjoy talking with you. Where can people find you online if they’re interested in you and your work and just kind want to keep up with you?
Dr. Caroline Mansfield (23:24):
So at the moment, I’m working at James Cook University, which is in far north tropical Queensland. So JCU Vet, it’s probably the best link for that. It’s a pretty cool place to be. It’s just right near the Barrier Reef and get to go snorkeling and hop up and see some crocodiles. It’s pretty cool.
Dr. Andy Roark (23:47):
That’s amazing. Oh man, thank you so much for making time and being here. I really appreciate you.
Dr. Caroline Mansfield (23:51):
Dr. Andy Roark (23:51):
Guys, thanks for tuning in today. Everybody take care of yourselves. Thanks for being here. And that’s it. That’s what I got for you guys. I hope you enjoyed it. I hope you got something out of it. Thank you so much to Dr. Mansfield. She got up before six o’clock in the morning, her time to do this podcast, and that was wonderful. Thanks to Purina Institute for making this episode possible. Thanks to you guys for being here. And yeah, that’s it. That’s all the thanks. That’s the thank and night. Thanks to me for also being here. Thanks to my dog Skipper who came and sat with me when I did the podcast, thanks to my mom and my dad. And I’m just going to fade out. I’m just going to fade out on that. And that’s where we’re going to end the episode. Thanks so much everybody. Take care of yourselves. Be well. Bye.