Claire Mendis (00:01):
So the interest of my project is that we're working on something that is very much applied, so it's a behavioral issue that can lead to health issues. Laying hens so when they are kept, whether it's in the industry, but also as pets in your backyard, they can develop that behavior that is called severe feather pecking.

Elena (00:22):
You're listening to the Why & How Podcast, produced by the Ontario Agricultural College of the University of Guelph, where we look to answer big questions in agriculture, food, and the environment through casual conversations rooted in research. Hey, Talia, how's it going?

Talia (00:43):
It's been really good, Elena, how about you?

Elena (00:46):
Not too bad. Today was honestly a pretty great day for me, but I actually have just one more question for you.

Talia (00:53):
What's that?

Elena (00:54):
Why did the chicken cross the road?

Talia (00:58):
I think I know the answer, but tell me why?

Elena (01:01):
To get away from the other chickens displaying severe feather-pecking behavior. Okay. To me and Talia that was actually a pretty decent corny joke, but today's topic is actually pretty serious. Today we'll be talking all about severe feather pecking in laying hens, which remains one of the most challenging welfare and economic issues in the egg industry today. We just got done speaking with Claire Mendis, a PhD student who's been researching how probiotic bacteria can be administered to laying hens and potentially used to address this behavioral issue. So I'm curious, Talia, have you had any experience with chickens or laying hens in the past?

Talia (01:49):
I do have some experience, but I've actually never witnessed these behaviors. So it was a really fascinating episode to hear.

Elena (02:00):
Yeah, personally, I haven't had much experience with laying hens, but I've gotten the opportunity to see broiler birds at my friend's family farm in Seaforth, Ontario. So it was news to me that severe feather pecking was such a huge issue for laying hens in just the egg industry as a whole. So I'm very excited for our listeners to hear all about Claire's research and hear about the impact that this has caused on the industry.

Talia (02:31):
Yeah. Well, let's dive in.

Elena (02:33):
So let's get right into it. So, Claire, it's really nice to have you here to talk about your research. We know that you are looking into some underlying causes of severe feather-pecking behavior and laying hens. And I know I don't personally know much about laying hens or that type of industry at all. So I'm pretty sure this is going to be a pretty exciting conversation, very informative for myself and for a lot of the listeners. So thank you for coming on. How are you?

Claire Mendis (03:02):
I'm good. Thank you. And thank you for having me, it's my pleasure.

Elena (03:06):
And I also understand that you did your masters in France in agricultural sciences, but you were majoring in animal production. So I'm just a bit curious, what drove you towards researching the area of animal production and animal biosciences, things like that?

Claire Mendis (03:23):
It's actually, it's pretty common. I'd say I always wanted to be a vet as a kid. And in France, so the school system is we have universities like you have in Canada, but we also have a different path, which is actually very common to go towards vet school. And it's kind of an undergrad, but very different at the same time, it's basically a pathway to an exam that brings you to a master. And so those studies are common between vet school and the kind of master that I did. And so throughout my studies, I kind of changed my mind and went toward this path. But I always knew I wanted to work with animals, that was something I was absolutely certain of. And the research side came when during my master, I did a gap here. So I took a full year to travel around the world and work at many different places. And somehow 90% of the internships I did were research-based and I truly loved it. So then it wasn't really a question anymore, it was just what I liked to do.

Elena (04:38):
Right. That's so cool. So I know you said you know you always wanted to work with animals, so did you grow up in that type of environment? Did you grow up on a farm or anything like that?

Claire Mendis (04:48):
Absolutely not. I come from Paris, France, so it's city girl through and through, but I feel much more a countryside person than a big city person. I actually hate living in Paris, I'm much more comfortable in a small city size. It's very interesting because we had cats as pets, but never anything else.

Elena (05:19):
Cool. So I'm excited to dig more into this research, but before we get there, you said you're all the way from Paris. So what kind of drew you into the University of Guelph in particular and the OAC for this type of research?

Claire Mendis (05:33):
It was very random, to be honest. So I did my master in friends and after that I was working for two years. And at the end of my contract with my company in France, I wanted to have a North American experience. So I started looking for research jobs in either the states or Canada, and turns out that I probably didn't know how to look for those jobs because I couldn't find anything but postdocs and PhDs. And so I were like, "Let's do a PhD, it's just a job for three years." And God knows I was very wrong. So I started applying for PhDs and postdocs because I actually found a postdoc position with my current advisor, which was on a very, very similar topic than when I was doing inference at the time.
So I was like who knows? I know I don't have a PhD right now, but I'm working on something very similar, maybe they can change the postdoc into a research position. And so I sent now with my CV and they replied to me saying that, well, I didn't have the PhD, so I couldn't have that position, but they would be very interesting into actually hiring me for a PhD. And so that's how I got it because the topic of the project they send back was what I'm doing right now, and I truly like the project.

Elena (06:57):
Cool. I'm really excited to get into this. So just tell me about your research and just a little bit about why it matters today, why it's so relevant today?

Claire Mendis (07:08):
So the interest of my project is that we're working on something that is very much applied. So it's a behavioral issue that can lead to health issues. Laying hens, so when they are kept, whether it's in the industry, but also as pets in your backyard, they can develop that behavior that is called severe feather pecking. And so even though pecking is a natural behavior in chickens, right? They don't have hands, so that's how they manipulate objects, how they feed themselves.
But when they start pulling out the feathers and picking very strongly at feathers of other animals, other laying hens it can cause feather damage, it can cause skin injuries, and in the worst cases, it has been shown to turn into cannibalism even. So you can imagine that when you have cases of severe feather packing in your flock and you end up with chickens that are lacking 50% of their feathers or are injured or are eating themselves where it's obviously for the welfare of the animals, it's very dramatic, but also on the economical point of view, it diminished their laying capacities. And on top of that, it also looks very bad for the industry from an audience point of view. So there's those three main reasons, animal welfare, economic point of view and perception of the farming industry that makes this issue very important.

Elena (08:58):
So does severe feather pecking happen in broiler birds? Any other species or is it only observed in laying hens?

Claire Mendis (09:07):
In broiler species because the commercial birds are usually sent out before they reach maturity so they don't tend to develop that issue. It's been observed in laying hens, that it tends to develop very strongly around 40 weeks of age so when they are sexually mature. And so in broilers, basically we don't have time to observe this behavior. However, in the breeding flux, which do reach sexual maturity it's been observed it is not as strongly researching this species, the main focus is definitely laying hens. And something very interesting it's that only females develop the behavior, not males.

Elena (09:57):
So that's interesting. Is there anything in current research today that points to why it only seems to happen in females?

Claire Mendis (10:07):
I actually don't know because we don't observe it in males, I think that not a lot of research has been conducted with of them. We do have genetic lines in our research station that we breed ourselves. And so we have lines of males that are bred for severe feather pecking. That means that they're moms and grandmoms show that behavior, but the males they don't show it. No, I wouldn't really know, I would guess maybe mostly genetics plays a big part on whether or not they're going to show it as males [inaudible 00:10:55]

Elena (10:56):
Claire, tell me a bit about the key findings of your research and what do you think this impact will be for the industry?

Claire Mendis (11:02):
So the key findings of my research are that when you supplement the birds that are prone to show severe feather pecking, if you supplement those birds with a probiotic supplement, so in our case a bacteria, it can help prevent them to display this behavior. And so if we were to find a mean to apply that to a farm context, then it could show very positive because we could help decrease the frequency of that behavior in farms.

Elena (11:41):
Claire, what exactly is this bacteria and what is the actual effect that it is having in the body of the laying hens?

Claire Mendis (11:49):
So these bacteria is called the Lactobacillus rhamnosus. It is a bacteria that is known to have benefits on the health of the host. So bacterias are usually colonizing our gastrointestinal tract. So it can be found from our mouth onto our anus and regardless of the species. And Lactobacillus bacteria, so there's many different types of them and we were focusing on a specific one, but in general, they are very much present in the guts of chickens, they are very important. And so when you supplement these bacteria, it can have some health benefits, for example, it can improve the immune system and make you makes you more resilient to stress.
It can also help with absorption of nutrients from your diet. And it has been shown in mammals to able to modulate behaviors through what we call the gut brain access. And so this access is basically how your gut communicate with your brain and so through many different pathways and it can influence your behavior. And so this is what we were looking at in my research how with a supplement of beneficial bacteria, we could beneficially influence their behavior?

Talia (13:22):
I'm just going to pop in here. I just have a quick question about the probiotics, in these cases, how are the supplements given? Is it through feed to the animals?

Claire Mendis (13:34):
That's actually a really good question, and I was part of what I was discussing in my thesis. So we gave our supplement to the birds via water, so the bacteria was dissolved into a fixed amount of water and we gave that to the birds every day. If you think practically on the farm system, it might not be the best way because you don't necessarily control how much water is ingested by the bird. There's also depending on how you clean your system is it can influence how well the bacteria are going to colonize the system. So a different way is via feeds. And this is something that we did not look into, but is very much used in farming system.
I know, for example, in the broiler industry, there is a lot of supplements giving via feeds. They might not be for similar research outcomes that we were looking at, but it's definitely something where you could think we could adapt our methods and translate it from a weather vessel to a feed vessel. And who knows, maybe it might also change the results, right?

Talia (14:57):
Yeah, that's so true, that's such a great point. And that's sort of how I was thinking about it too, in the bigger picture of larger farming systems. And I just sort of have one follow up question, like how long did would it take for the probiotic supplement to work in a laying hen.

Claire Mendis (15:21):
Again, a great question. So when we first started, we decided to give our hens this supplement for a minimum of three weeks. Because in nutrition studies, it's usually the amount of time that is considered for a supplement to actually have an effect on the host. And when I'm in host, I mean, like the animal who gets the supplements. We actually found out that the specific bacteria doesn't necessarily need three weeks to have an impact, and the impact can be very quick and very transient. So in studies from our colleague using this same bacteria, they found for example, that when it was supplemented in the gut, it could have an effect within minutes, which it was very surprising. And so in our research, we actually found out that the bacteria was able to have very short term effect and also some more long term effect.

Elena (16:33):
So, Claire, I'm just curious, are these supplements meant to prevent severe feather-pecking behavior from manifesting itself in these birds or is it to just stop the action completely?

Claire Mendis (16:47):
That's very interesting. So I would say in a perfect word, it would be both because you would like to be able to prevent him from ever happening, right? But if you're unlucky and the behavior starts, you would also want to be able to stop it. And so in my research, we conducted three experiments where we actually tried three different ways to use that bacteria. So we first used it as a continuous supplementation, meaning that we first gave the supplements and then we stressed the birds while keeping the supplements going on, so that was a continuous way.
We also tried a prevention method, so first the supplements, then we stopped it and then we stressed the birds. And then we tried out more curative methods. So we treated the birds with the supplements and stress at the same time to see if it was able to act immediately. And why I mentioned stress is because stress is actually a major risk factor for the development of severe feather packing, so it was kind of our way to trigger it. And from our results or my results, but there's always many people involved in our research projects, so from our results, we found out that the bacteria as a prevention alone doesn't necessarily work very well and that it was more effective as a continuous supplementation. So basically you want to give it to your birds every day and continuously.

Elena (18:43):
And do you mention stress? So I'm just curious, does this stress, do these conditions mimic what birds will it experience in farming conditions?

Claire Mendis (18:51):
Absolutely, so that was something that was very dear to me. I wanted my research to be as applicable as possible for farmers. Because what's the point of using stressors that the laying hens are never going to encounter in their lives. So in our case, we looked for stressors that were actually previously shown to be effectively stressors for laying hens and that were as close as could get from situations that they would encounter in their lives, lives on farm. So, for example, one of our major stressors was to mix them with unfamiliar birds. Because laying hens when they are kept on farms, so they are usually housed with thousands of other birds.
And we know that they are able to build a hierarchy and relationships with birds, and they are able to recognize up to a certain number of birds, I think it's research has shown that it was like around 90 other birds, but they can't remember thousands of birds. So it's like if you were to meet new people every day, which can be a chronic stressor, right? So in my research, we had birds kept in different pens and we mixed those pens so to kind of mimic that, so they would meet new birds every other day. And also or switch pens, so they would meet those new birds, but also be transferred into a new environment. So different smells... I mean, technically depends were as identical as can be, but it's still with their senses, it still feels as a new environment. So mixing the birds was a major stressor.
We also manually restrained them to try to mimic when the birds would be transferred from one facility to another because the birds are first kept in rearing facilities until they reach sexual maturity. And then around those like 16, 17 weeks old, they are transferred into a laying facility, which is built for getting the eggs and keep the birds up to their needs. And so to kind of mimic the handling that they are not used to and happens in their life, so we manually restrain them. We also physically restrain them into transport crates and so it is a tiny environment where they are kept as a group.
And we also restricted their access to environmental setups. So for example, birds like to perch, especially at night, so we actually removed those perches from their pens. When they were laying, we actually are also restricted their access to the laying nests. All of these two create chronic stressors in hope to trigger the behavior.

Elena (22:18):
Interesting. Now that I know sometimes I guess birds will experience these conditions, sometimes not all of them, but sometimes one or a few of them they would experience in farming conditions. So are there any current methods that are presently being used to manage severe feather-pecking behavior, if it is shown due to stress?

Claire Mendis (22:48):
Yeah. Absolutely. Maybe not necessarily due to stress because technically on farm, you're not supposed to have any extra stress. The one I mentioned are linked to handling techniques and like, there's not much we can do around that. But so to control for, or to try to diminish severe feather pecking on farms, there's definitely techniques that have been used. The thing is none of them are 100% effective. Some of them sometimes will work, some of them won't work.
But around the main techniques, so the big trimming is a major one and involves at a young age removing part of the upper mandible of the beak in laying hens. So this doesn't prevent them to peck or to feed, but it does make their pack less strong. So the impact when it doesn't prevent them to actually show the behavior, it just diminish the outcome of this behavior because they're not able to necessarily really impact as much damage. Other techniques that are not on the birds might. So the use of enrichments, so for example, adding pecking stones or a bunch of hayes and the use of red light. The use of red light can help to diminish the behavior.

Elena (24:26):
So, Claire, I'm wondering if you could tell me what are some obstacles you've faced so far in your research? Or what has been the most challenging parts of getting this information and really trying to understand this behavioral issue turned health issue that is so prominent in the industry?

Claire Mendis (24:45):
I'd say that one of the main challenge that we actually had on the practical point of view is that our stress treatments wasn't necessarily effective in triggering the behavior, so that was definitely a challenge. And so we actually had one experiment when the hens were young and we know that the behavior tend to appear when they're older and the hens didn't show any of the behavior or not much at least. So that was definitely not very satisfying and yet that happens. On the theoretical point of view, a major challenge from my thesis is that I'm looking at a concept, so this gut brain axis, so this communication between the gut and the brain.
And this concept is actually quite new, I mean, new on the research side. So it's been explored in the last 20 years, which means that we still don't have much knowledge about this and especially in laying hens. So much of our ideas and hypothesis are actually based on what we know from mammals and not everything is translatable. So whatever, for example, some physiological pathways that we know from human studies and rats, or my studies and what we thought were translatable into birds appeared that they were not. So that was definitely a major challenge and we need more and more and more experiments on these to be able to build more knowledge.

Elena (26:30):
Wow, that's interesting. So I'm wondering when exactly was severe feather pecking, when was that really noticed as something to be taken seriously in research or something that was really proven to be both an economic sense and an animal welfare sense? When was that proven to be like so detrimental that people started to look into it for these laying hens?

Claire Mendis (26:57):
It was noticed such a long time ago, there was more than 50, 60 years of research on severe feather packing. And the reason is because we still don't know everything about it. We are still unable to find a way that is 100% efficient against it or to prevent it. So back I was going to say in the old days, but previously, researchers thought that severe feather pecking was a translation of frustrations from the animals because on farms, they were kept in settings that were quite poor environmentally speaking and sincerely speaking compared to what their natural appetite would be.
So they thought that it would be an expression of that frustration, for example, the lack of foraging substrate when they were kept on farms or even on floors with not much to forage from. It turns out, it might be a component of it, but it's not the entire reason because if you have chickens in your backyard with the best quality of life that we would think of as human, they can still develop that behavior and even provided with different enrichments it still can develop. So this is why now we're looking at it from a more internal point of view, a more fundamental point of view that maybe it's not because of the outsides of the bird its environment, but maybe it's something from the inside of the bird with a dysregulation of something.

Talia (28:44):
Just add on to that and the concept of something not being regulated internally within the lane, and is that where your idea came to introduce a probiotic as a supplement and really look at the gut brain access and translate that research in mammals into birds and laying hens.

Claire Mendis (29:12):
So it is kind of where it comes from. I am obviously not the first person working on this. My PhD comes from my advisor research who has been working on this topic for much longer than I have and previous people before her. But so to give you a global context, previous research, working on this idea of a dysregulation of the gut brain axis, I actually found out that birds who show high frequency of severe feather-pecking behavior are lacking these Lactobacillus bacteria in their guts. And we know from mammals research as these bacteria are actually beneficial for health and behavior, they are already used as supplements. You can find them in your grocery store, right? For anxiety, for so many different things because they are globally beneficial. And so nobody try to supplement those birds that we know are lacking the bacteria with these bacteria to see where it would lead. So this is what I've done in my PhD.

Elena (30:32):
Right. And as you mentioned, there are other researchers that are looking into the possibility of really incorporating these probiotics into the farming conditions and seeing how that could play out in the actual industry. But are there any new questions on your end? As a researcher that is exploring this, are there new questions that are arising for maybe future researchers to carry on in the future?

Claire Mendis (31:02):
I would say that mainly those questions from what I've been focusing on would be whether a single strain of bacteria. So I did using one single type of bacteria is sufficient, or maybe a combination of those bacteria would be more efficient, right? Because the bacteria I used is not the only one, there is many types of bacteria that we consider as probiotics. And so maybe using a combination of them would actually enhance the beneficial effect, maybe not, but we need to try it out. There's also the question of the dosage. I gave my birds a specific dosage, but maybe more would be more efficient, maybe less would be more efficient. There is obviously the question on how to deliver those supplements, which we already mentioned, and that has to be looked into. So those would be the questions that come to mind right now.

Elena (32:09):
And what advice would you give to an aspiring researcher? Just someone interested in learning more about this topic?

Claire Mendis (32:15):
Oh, that's a good question. I mean, so far they're only good questions. It depends on which point of view I would say that it is definitely area of research where you need to be prevalent, because you need to learn about neurobiology, immunology, but also microbiology and behavior on top of that. So you need to definitely have an interest in many different topics. Although not having prior knowledge doesn't necessarily prevent you to go this way, because I had no knowledge about most of my research. I mean, I knew about the behavior, my research before, but not those fundamental parts. So that would definitely be an advice to know that it's going to be a very much diverse research.

Elena (33:20):
I just want to ask, before we go, is there anything or anyone you'd like to give a shout out to or perhaps is there anything fun and exciting that's happening in your life that you'd like to share with the audience?

Claire Mendis (33:32):
Yeah, absolutely. So, first of all, to thank people around me, obviously my advisor because she brought me where I am now. I mean, we work together for four years and a half now, so it's been a long time and we have this great relationship where I have lots of freedom and this is really something that has been important for me to be able to be very independent in my work, but yet have all the support I need and when I need it. So my advisor, sorry, Alexandra Halander, because I don't think I've named her. And also to our lab manager who is [inaudible 00:34:19] basically have acted like a second manager to me on top of as a friend. So those two people definitely for my research has been extremely important. And as for exciting news, so as I mentioned that you can bring your skills from one piece she's to another, I am now moving on to cattle which I've never worked with, but so after my PhD, I'm going to start a position as annual welfare researcher in dairy cows and cattle.

Elena (34:57):
That's amazing, that's great news. I'm wishing you all the best for your future and I just thank you so much for coming on and sharing about your research and about your passion.

Claire Mendis (35:07):
Thank you so much for having me.

Elena (35:12):
The Why & How Podcast is published by the Ontario Agricultural College of the University of Guelph. It is produced by Jordan Turkstra and Talia Dyer. Reporting and editing by Jacob Isaac and Kyle Richie. The host is me, Elena Baker. If you like what you've heard, be sure to leave us a review and subscribe. Thanks for listening.