Larval Nutrition: Feeding some of the smallest vertebrates on earth

Corinne

Welcome back to the Salty Talks podcast. This is your Go to podcast for information about the aquaculture sector in Maine. So today I'm here with Matt Hawkyard, who is the assistant Extension professor and finfish nutrition specialist. Wow, that was hard to say.

Matt

I've been practicing

Corinne

At UMaine's, Aquaculture Research Institute, so I'm going to turn it over to Matt to introduce himself more.

Matt

Yes, thank you. And thanks for having me here on your podcast. I'm really excited to be here at the IMRC recording today. I'm a relatively new professor here at the University of Maine. I've been here about a year and a half. I have a joint appointment with the Aquaculture Research Institute and then, UMaine's cooperative Extension. So I have this really a fun and interesting job where I'm able to well, I'm working on themes regarding finn fish nutrition and specifically within aquaculture. So things like trying to solve or not solve myself, but solve as a collective challenges that we've got with, you know, fish meal usage. Currently, the industry uses a lot of fish meal in fish feeds, and those are from wild capture or fisheries. So one thing that I'm working on is looking into alternatives for those ingredients, things like soy meal. One of my first projects here at university was looking at insect meal as a replacement for fish meal. So that's one of the themes that we've got going on here. But I work largely in larval fish nutrition as well, so I'm trying to grow fish through a really challenging life stage. I think we'll hit on that a little bit later in the podcast, but because I've got this joint appointment with Cooperative Extension, largely we're doing a lot of applied research things that are going to have a positive impact on the industry in both the short near and the long term. Changing the ways in which we feed fish that might be through improved feed technology, through new and innovative ingredients. Doing things that improve fish health. So really looking at every problem I've got, I always come at it looking at it from a nutritionist standpoint, but really trying to advance the aquaculture industry in a very concrete way.

Corinne

Thanks, Matt. So, as he mentioned, today we're going to talk about finfish larval nutrition and some of the challenges associated with that. Before we get into sort of the more detailed nitty gritty of that, I think we should start at more of a bird's eye view of finfish aquaculture in the US.

Matt

Yeah, I spent a good amount of time thinking about saltwater fish. So marine finfish are kind of a group of species that we often kind of just cluster together here in the United States, largely because we just don't have a big marine finfish industry here yet. So what we do have in the United States at this time, I'm sure I'll leave some really important folks out, but the big players are Atlantic salmon. And so we have a pretty vibrant Atlantic salmon industry here in the state of Maine. When I talk about marine fin fish, there's this big opportunity where. As an industry or as a society. Seafood is one of those things that we just it's a limited commodity. We're importing a ton of seafood each year. About 90% of what we get in the supermarkets is imported from overseas. We're in a huge deficit. That number, every time I talk to an economist goes up. The last number I was throwing around was about a $13 billion aid deficit. I think it's well over that now, but so how do we address that deficit? And how do we do that as countries are tightening down their own food supplies? You look at some of the things going on globally right now, and countries are really looking at their own food stability in the long term and having a healthy source of seafood, of fin fish. That's what we mostly eat in the united states. Our top five species are all well, four out of the five are finfish species. So how do we expand that? And how do we do that without further exploiting freshwater systems, which we already know have a lot of competing resource use? You know, really looking at marine finfish as this opportunity to grow something that people want, they need it. It's nutritious for them, and we can do that in a saltwater environment. We're growing these fish domestically in the US.

Corinne

Can you highlight some of the species that we're growing and maybe some of the species that you've worked on in your research?

Matt

g on dorsalis since, I think,: 2003

Corinne

So when you are saying that you're finding this fish at the Sushi restaurant, is this wild caught fish that we're talking about, or are we talking about farmed amber jacks? Becasue they're farming it in Hawaii, right?

Matt

Yeah, that's right. So both so actually, we do see there are some wild caught amberjacks that do go to the Sushi market, but there is, I think, a large fraction of it overseas is farms. So when you actually look at the Japanese market, they're pretty effectively farming the Japanese amberjack. Here in the United States, we do have at least two commercially existing cereal of fish farms. So one of those is in Kona, Hawaii. And so my grad student, Kara Chuan, had previously worked for them and now is doing thin fish nutrition work here at the University of Maine. And they're largely working on an offshore operation. So they've got a land based hatchery. So you could imagine when I say a land based hatchery, this is a place where they bring in adults. The fish spawn the eggs in a big tank, and we collect the eggs out of that tank. And these eggs are little. They are like rain of sand. They are basically one adult female, and might have a million eggs. And this is really what's gotten me interested in this kind of area of aquaculture and and just broadly how I kind of got roped in the subject. Just that concept of having this amazing looking fish that looks, like I said smaller, but something tuna like for those who aren't familiar with the species. And yet the way they reproduce is to spread, you know, half a million eggs into the ocean. They would just spread it into the ocean currents. Those eggs would flow, float around like seeds in the wind and hopefully some of them would be in the right place with the right temperature and then the right food is a really critical thing. And that's been recognized for a long time as how important food is for these great populations in our world's oceans. But it's similarly just that important in aquaculture settings. So that's really what got me interested in this idea of larval finfish nutrition. But I really dig rest there. I think we also have a recirculating a land based facility here in Maine, in Hawaii. They have to do the early life stage stuff in the hatchery. Land based, pretty much all that's true for all of these species. And then there are different options. Then once you get through the early life stages in the hatchery, you can move them out into one of two kinds of options. You can either put them out in the ocean in big net pins as they've then matured into larger fish that are easier to keep in these large pins. The other option is once they reach juvenile stage, you can move them into a recirculating aquaculture system from the hatchery. And so these are large land based facilities. I think both of these any system, any agricultural or aquacultural system has benefits and drawbacks some of the environmental challenges that we have seen in some sorts of net pen farming. We're able to avoid those things in these recirculating systems. So cereal is just interesting in that way. We see these two different models and both are potentially successful ways of going about growing fish. But my focus is really in the early life stage, how do we get them through this hatchery phase, which is a big bottleneck in the culture?

Corinne

Yeah, this is a pretty good segway into talking about your research and also just feeding, I guess feeding fish in general when they're in a recirculating aquaculture system. The challenges associated with you said you're feeding these like teeny tiny little things that are so hard to see and what they're eating, feeding the adults.

Matt

There will be some differences there. That's probably enough for a whole other podcast, to be honest. And there's a lot of interest in how feeding fish is different from delivering feed into a net pen in the ocean where the food kind of goes through and 1s largely consumed with the waste products are diluted into the water. And some of that does impact the Benthic community, but the waste products are largely being lost for diffusion. And what we do is we try to place our facilities in ways that those are going to have the least amount of environmental impacts. They choose places that have high flow rates to kind of wash the waste products from the farm away. The challenge when you move to a land based system is that you are now retaining all of those waste products in your system. And so whatever you put in the system and food is one of the number one inputs. That all turns into something the fish are it turns into fish growth. So most of that food and fish are very effective at turning food into growth. Some of the most effective among animals that we culture, I mean, broadly speaking, even when compared to pigs and chickens and cattle, this idea of having them swimming in their own in waste products is very challenging. Technology is there to clean most of that stuff, and the animals actually have a very high quality of life in these systems. But nonetheless, we have to control the fact, the input there, the feed, and just appreciate that that's going to impact the system directly. So that's an area of research that is kind of emergent is how do we look at those two systems differently and how do we solve those challenges? And like, I think that's a whole separate podcast that hopefully we will come back to you in the future. But feeding fish larvae is really interesting in its own unique challenges. So we're trying to feed among the smallest vertebrates on Earth. I think a Tunicate Ecologist once commented that there are tunicates out there that are smaller than my precious little fish larvae, but they are really small. So I make this kind of really gross analogy sometimes to people that if you're, like, clipping your nails into the toilet and you look down into the toilet, those clippings that's not much large, they would be a similar size to what, looking down into a fish tank and seeing fish larvae swimming around. Yeah, sorry, I know that's gross, but really, the imagery there, and I do love these animals, so I don't mean to disrespect them with my toilet humor. And there's millions of them. One female have several hundred thousand eggs in a tank. And so you can imagine we're feeding, to my knowledge. Well, I don't know, we're at least feeding the smallest cultured vertebrates on Earth. Save something for research, but for food supply, there's just no real analogy for that. There's no little baby chickens that are going to be smaller than what we're dealing with here. And even salmon people are like, well, we've been doing it with salmon for 100 years. But salmon have these monster eggs. I know a lot of people know how big these salmon eggs are, and we measure salmon eggs or whatever. Sorry, I guess I should know the dimensions of the salmon egg, but they're like 8 mm or so wide, whereas would be my best guess. But these marine fish larvae, they're average

Corinne

perfect.

Matt

Was it eight?

Corinne

Yeah.

Matt

Thanks. But about a millimeter is the average diameter of fish larva. So you could actually pack and if you did the 3D thing, you'd find you could actually pack, like, 50 eggs, 50 marine finfish eggs into a salmon egg. And that difference in size really changes how the fundamental, fundamentally, what they're eating, what size their food is. Because now you're feeding something. You know, fish can only eat what they can fit in their mouth. So if you have these smallest vertebrates, they have to have these just little microscopic things to eat. And we've been doing that for about 100 years, but really only well, since the 60s. So what people realized in the 60s that really transformed things is that we could use cultured zooplankton. So these little critters that would normally be found in the water are like copepods, though in nature, Fish are eating Copa Pods, and those invertebrates are eating plankton, right? Phytoplankton. So they're in the wild. You can imagine the fish larvae floating around, kind of surrounded by all these little Copepods swimming around. They're surrounded by this green microalgae. And what we're trying to do is replicate that. But the problem is we're not very good at growing Copepods. People have tried and that is the challenge. It really just doesn't scale well. The economy is just not very good for Copa Pods. So you need these really large systems just to put out very small quantities of them and we just can't really afford to do that. But nutritiously, they're great for fish larvae. So you have to find something else that is not a Copa Pod that you can collect culture easily instead. Exactly. Yeah, that's where people really started. That was how marine finfish aquaculture really started, was finding things like rotifers. Rotifers are another like an estuarine invertebrate that you would find in estuary waters just kind of swimming around with copepods. But the difference is rotifers we were able to culture and captivity really very densely. So the females actually lay eggs and then those eggs become females. And that's one of the properties that is asexual reproduction. That happens pretty rapidly. They have a pretty short life cycle and they replicate at very high rates. So rotifers are where we can grow them, we can grow them in very dense systems and that allows us to then grow fish larvae. And then there's another one, brine shrimp. So if you've ever seen sea monkeys marketed to the kids at the store, those come in little eggs and those eggs are again around a millimeter big. Not even that. Sorry, much smaller than that. But they look like grains of sand and you'd place them in salt water and then after 24 hours they hatch and there's little swimming invertebrates. Well, those sea monkeys, we call them brine shrimp in aquaculture and they make for really good food for early feeding marine fish larvae. They're a little bigger than rotifeifers. Usually start with rotifers and then you transition them onto artemia and every species is a little different. I said we have 19 species, but that's kind of the general recipe and some species won't take either one. And then you get into a real big challenge. But so they would, in the wild, be eating Copa Pods,

Corinne

if I'm understanding you. But we can't culture Copa Pods very well. So we're feeding them these rotifers or brine shrimp. And so they have the same nutritional content that Copa Pods would have.

Matt

Yeah, no, really good question. Yeah. So that's been recognized as one of the many challenges that we face feeding fish alive. So step one was just finding something they'd eat, which we're taking these animals and putting them into tanks and just having it. Something that they eat and eat and kind of grow on as a first cut. Kind of the best we could do. But definitely in systems where we've been able to feed larvae, Copa Pods, even though it's not economic, we see that they grow way faster. We see lower rates of malformations in animals that just don't quite develop normally because this is largely nutritionally based. They're just not getting adequate nutrition. And so we're trying to solve those issues. One strategy is to say, well, we know that fish and river do really well on Copa Pods, but we know that they don't do quite as well as on rotifers. For example. What we can do is we can evaluate, look at the Copa Pods and you treat that as kind of a gold standard and look at exactly what are they made out of and what properties do they have and how do rotifers differ. And so in my PhD research, for example, I was looking at touring. Touring is this it's like an amino acid. It's in things like Red Bull. The science actually on that says that you don't get a lot of benefit from touring if you're doing a time trial unless you have suffered some sort of cardiac damage in life. Just a little bit of a Red Bull. I want someone to take away something useful from this podcast. Just so you know. It's the caffeine that probably does the most. But the point is that both cats, cats have this obligate nutritional they're nutritionally obligated to eat touring. If not, cats will actually. They're not going to grow and develop, but they can develop cataracts. They can actually get really ill if they don't have touring. Humans were able to take other amino acids and turn that into touring. So we don't have that requirement. So for a long time, I don't think people really appreciated that in carnivorous fish. They, they just assumed that we were there, or for whatever reason, it got lost. That really the importance of this torrent, this nontraditional amino acid touring. So sulfur amino acid. Anyways, my point is, it was really rich in copepods. It was like 1% of their dry weight, and that's very high when you compare it to rotifers. We couldn't even measure that nutrient in rotifehorse. And so what we realized was, well, hey, if we can get that touring into the rotifers, we can actually get the fish growing more like they would on copa pods. That's why I did a lot of my PhD work doing that. Then you get into a whole another suite of challenges, and I don't know if you're ready for that. So now we're growing fish. We're growing things to feed things, which is unusual, that's not done a lot. This idea of live feeds, rotifers and army, actually, we have a whole separate crop just to feed our fish. Now we're talking about trying to manipulate that, initial those live feeds so that they're more nutritious. And so in order to do that, what I've done is looked at microencapsulation. So can touring dissolves into the water? It's a water soluble nutrient, and there's a whole suite of water soluble nutrients. So things like vitamin C, most of the all the B vitamins are water soluble free amino acids. So things are very essential for things to grow. I mean, nutrients that are essential for for animals to grow, but they're water soluble, so we don't think about this. When you're feeding pigs, you just put food in a trough, the pig eats it, and then they grow. But we're working in an environment where the animals live in water, and so it's a very different environment, and the food has to transition to that environment. So what happens is, if you put touring in the water, the rotifers can kind of drink it, but it's not very efficient. And our goal is to get them to, like, 1% of their dry weight. So that's a lot of touring. And people have found if you just dump gobs and gobs of touring in the water, you can get rotifers eventually up to that level. But what I found is you can actually encapsulate that touring into a little micro capsule. In this case, it's liposomes. I didn't invent them. I just adapted them from pharmaceutical use and with the help of colleagues. But what we found is that if we encapsulated these water soluble nutrients. They could feed them directly to these live feeds and make them look more like copepods from a nutritional standpoint. And it's really efficient. And it's about 60 times less of that of touring when compared to just dumping it in the water.

Corinne

Yeah. So that's a lot less well, it's probably more cost effective, right?

Matt

Yeah, it should be more cost effective. I mean, the microencapsulation method needs scaling, so that's kind of where we're at with that. But presumably, if you could scale that technology and that once that happens, it would be a way of doing it without the added step of just dumping that in with a much less usage of touring for your animals. But I think touring isn't terribly expensive. It's when you start getting into more water soluble nutrients, things like vitamin C, your vitamins. I mean, hypothetically, you could encapsulate this full little water soluble package and make your rotifer look from a water soluble nutrient standpoint, just like a cobra pod. And they've been doing that with lipids for a long time. They're much easier to study. So there are products out there for changing the rotifers and artemia. If you've thought much about central fatty acids, these are lipid based nutrients and they survive the water much better because oil and water don't mix. So it's a lot easier to get oils into fish than it is to get water soluble things into fish. Just the nature of the challenge. Is that something that you keep talking about in terms of rotifers?

Corinne

But is that something that is also being studied and worked on getting these micro perapsulated touring into brine shrimp as well? Or is this just specific to rotifers?

Matt

Yeah, I think more broadly speaking, Torin is my example. We used it as a kind of example nutrient, but really a whole suite of water soluble nutrients. But yeah, it's not just rotifers. We actually have found that you can use these same microparticles for elevating the concentrated essential nutrient concentrations of artemia as well. And they weren't as efficient in touring, so it's probably other nutrients that would really have more applicability to but certainly the capacity is there, but the real next step is that we kind of want to get away from rotifers and artemia. So if you have to grow something to feed something that is actually your target crop, that's pretty inefficient. And then now you add the fact that you're growing living organisms. Rotifers are like a continuous culture. It's almost like a sourdough start. You have to take a little bit and put it in the water, and then that multiplies, but it changes it over time. And you can have just like your sourdough start. If you don't take care of it well, it'll crash, and you can't use that in the next loaf. And you have to go find a new start,

Corinne

Literally, my start during early COVID.

Matt

Yeah, that just happens. And that's part of working with living organisms. And so with rotifers, we definitely see that people that are live feed managers live a very stressful life when their whole hatchery what, they've got thousands, if not millions of fish, depending on if you're talking about fish larvae on hand that they're responsible for feeding. It takes a lot of staff just to grow these rotifers. So you'll have these huge tanks in a hatchery and a few staff that are just designated for just growing the rotifers. And so that's a huge investment on the part of the hatchery because they have to pay these technicians, they have to have the footprint, they have to have the energy and feed inputs and all this stuff. And then yet on any day, it could just crash. They could just be gone tomorrow. Gosh. Yeah, I mean, usually it doesn't happen like that. Usually what you see, you'll see a dip one day, it's like, oh, no, they're not pre producing like they were two days ago. And then all of a sudden you. Stressing out. And so, you know, really hatcheries want to get away from that. And ideally, we would feed them and prepare feed like we do for juvenile fish. You know, with juvenile fish, we just put everything the fish need into a small particle and then feed them that. So fish food are these extruded feet based feeds, but they just look like a bunch of brown, dry like pellets. Yeah, exactly. Yeah. So ideally, we'd be able to do that at with fish larvae, and there are some commercial options for like, late stage larvae. But right now we're still pretty dependent on the idea that we're going to have a rotifer phase and then they grow. If the fish grow, then they're able to eat artemia. So we transition them onto artemia and then eventually they're on artemia for a while and we co feed them with the artemia and some dry diet for a while, this artificial feed, and eventually, eventually that they become feed trained and then they're on this artificial diet. Then life gets easy and less expensive. But what we're just not able to do yet is come up with a micro particle that we could just feed to them early on. And that's a big area of my work.

Corinne

So is that like a size thing, or is that because it's hard to get something that's water soluble into a dry feed particle?

Matt

Yeah, it's absolutely like a size issue. So the scale is everything. In this case, the challenge is we're feeding the smallest vertebrates on Earth, so they have to have the smallest fish feeds on Earth. And here's, for the mathematicians out there, it's a surface area to volume challenge is what we're really dealing with. So if you've got a really large particle, then it has a relatively small amount of surface area. So the outside of the particle is relatively minor when compared to what's on the inside. So think about like a basketball. Actually, what I like to do is think about a sugar cube. So if you take a sugar cube and you drop it into water, it takes a while for it to dissolve, right? You'll be sitting staring at that sugar cube for quite a while. But if you take sugar in the raw, which is like, more crystalline, that dissolves faster. And then better yet, if you took powdered sugar and put it in the same glass, it's gone like that because the particle size are small. And so the surface area with respect to the volume of those particles is so much smaller that it dissolves faster. Those water soluble components enter the water faster. And so that's what's happening as we move from a juvenile feed that these are like the size of salmon eggs. You can imagine the salmon egg is not too different than the size of an extruded feed, which we now know are 8 mm. Is a salmon egg size

Corinne

8.3? But you're closer

Matt

Haha Okay. But the particles that I'm talking about, these that you would feed, might replace, used to replace artemia. For example. If we could replace artemia, those particles, they just look like dust. You would have a handful of just dust, and they would be micro particles. And largely, you can actually make them by just making dust. One way they make them is they just take fish feed, stick it, and grind or grind it all up, and then take that and they'll catch it on like a sieve. So a screen that's just the right mesh size to sort out just the particles that you want. And that's what a lot of commercial micro diets are. They're just kind of ground larger fish food that's been ground up, and we feed that to the fish. But you can imagine that comes with a whole suite of problems. So one of the problems is that these fish, they're not juvenile fish. They can't swim as fast the world gets more viscous the smaller you are. So forget it's called the Reynolds number and oceanography. And if someone who's interested could go look up the map of the Reynolds number. But basically, if you're like a little critter living in the ocean, it feels like you're swimming around in jello. And if you're a big critter. If you're a blue whale swimming through the ocean, the world feels like air to you. That is very not viscous. These fish are they just don't have they're fighting viscosity and then there's turbulence in the water because it's more viscous. It's going to be moving them around, just a little flow movement. They're more subjected to that. And then they're trying to identify the feed and then swim to that feed and get it. And they're just not that great at it yet. I think they're better than when we look into a tank, we're kind of like, oh, they're horrible at it. They're actually not. They're more sophisticated than we give, and I think a lot of people give them credit, but nonetheless, they've got this big challenge. And so when we try to give them these artificial diets, one thing that happens, it just all sinks to the bottom of the tank. And so just my colleagues at Hubs and I did some back of the envelope calculations, and we think about 5% at best of the food that you put into the tank at these early, early stages is actually getting eaten. Yeah. And so the rest of it is sitting on the bottom, losing its water soluble nutrient to the water column, just leaching, as we've talked about. So when I said these water soluble nutrients are lost because the particles are small at the small scale, what's happening to those nutrients is they're being lost from the diet which we're trying to feed to the fish. So our feed is less nutritious for the animals because some of the stuff has been lost. And then the other problem is that those nutrients are going into the water. And now that we've got a waste problem, so that water now is loaded with nutrients, and then those nutrients can be used by things that we don't want, like vibrio bacteria, pathogenic bacteria could be utilizing that kind of soup that the animals are swimming in because their food is losing the nutrients to the water. So, yeah, so that's kind of where that's the world I live in, thinking about these challenges and like, how can you be better, how can you make. Diets for these microscopic animals that can survive this challenge of passing through the water and not impact our system. So we're not creating a soup that the fish larvae swim in, and it's a big challenge. And we've got a couple of different ways of attacking this, I guess, so to speak. But one way is to make live feeds better and more efficient, and then you need less of it. You can get the fish through that better. And then the other strategy is to be able to grow Copa Pots better. So that's not something I've worked on. I may have grown some Copa Pods in my day, but really, there are whole groups that are just saying, well, what if we found the right Copa Pod that replicates fast enough and that we find the right culture conditions that can make them more efficient? And that's a whole other area. And maybe that will happen. I'm a little skeptical that that will happen in the near term, and then the third option is coming up with a formulated feed and an artificial diet that, you know, doesn't sink as fast. So that's one of the issues, that the fish can't eat it. It sinks faster than they can physically grasp it, this thing. And I've been talking about losing their water soluble components that we call that nutrient leaching. So if we can come up with diets that are more neutral and buoyant and that don't lose all, are not prone to leaching or are less leaky, then they have to be digestible. And then finally, if they have the things that the fish need, they have to have a whole suite of different nutrients that just like any other animal does. They have their nutrient requirements. So we have to meet those needs, but we have to solve these kind of physical problems to get there.

Corinne

That sounds like a lot that sounds like a whole slew of problems and things to consider.

Matt

This is why I have a tough, tough time with an elevator speech for my talks. If you were in an elevator and I've got 30 seconds to break this down to you, they'll normally get to that depth. So it's nice to have a podcast to break it down and, like, it's like it's about the third layer down. You finally get into the stuff that I do. I also think people in general don't even realize how much goes into fish feed. And all of th Thought and the research and the complexities that are behind it. It's nice to have an in depth explanation of that.

Corinne

Do you want to talk about other projects that you have going on?

Matt

Yeah, jeez, lots going on right now. I think some of the key projects that I wanted to highlight, one, we just got this National Sea Grant Fund, Occupy Your Award, to look at some ways of improving microencapsulated diets that are kind of similar to what's on the market now. So we're taking what's the most successful at present. And then we're going to try to adapt that using some kind of fun new technologies. And that's working with a main company, Kingfish Maine, as well as my partners down at Hub SeaWorld Research Institute. So that'll be fun. That's all going to be directed at California or Cereala. So California yellowTail and Amber jack. And then we've got another project which is funded by NOAA, but to actually develop these really novel microencapsulated diets, so very different than anything that's out there, basically, we're taking these I mentioned Liposomes and how we really were able to use those for enriching rotifers. But what we said was, hey, can we just put those into an inert particle, a carrier particle, because they're so good at retaining their water soluble nutrients and then put other stuff in there that fish need. And so what we call those complex particles, my advisor Chris Langdon coined that term. But these complex particles, you're taking two particle types and putting them together like a super particle. This is one thing that we're working on now. We're also doing some work with lumpfish, trying to develop hatchery feeding protocols for these cleaner fish. So salmon are prone to getting sea lice. And in the main waters, we're not able to use any sort of chemical therapeutic, pesticide and so because of that, and we wouldn't want to anyways, but there's kind of limited options. You can physically remove them and they have some means of doing that through kind of like a jet removal process. But we're looking at the Norwegians who have really taken these lumpfish. They're a little cleaner fish, really cute, and they eat the sea lice off the same fish. You could just put them in the pen with the salmon at a certain rate. And so we're working on developing some nutritional protocols for feeding lumpfish. And down the road, I'm hoping to do some diet manipulation with that speed. As well to kind of solve this biocontrol felice issue or make it more efficient, I should say. And then we're working with this with another main company right now. They're a startup phytosmart, and they're actually growing a micrology that's really rich in DHA and land based systems. And then they've got a very nice process for preserving those microalgae cells where it's done in a way that doesn't lead to very low levels of kind of oxidation, loss of some key nutrients, and it's starting to get into the weeds there. But we think this will be very nutritious for early staged fish. And we're testing that as both an enrichment product for live feeds as well as they make a flake out of it. And we're testing that as a feed supplement to get these essential fatty acids to early stage fish larvae. And we're testing that actually in both marine and a freshwater system right now anyways, and in a suite of other things. But those are just some kind of key projects that I've got going on right now.

Corinne

You sound busy.

Matt

Yeah, I'm very busy. Yeah. And podcasting.

Corinne

And podcasting.

Matt

No, this is a highlight. This is really fun.

Corinne

That's awesome. So what does that mean moving forward next? Is it, I guess, for the aquaculture industry? Is that like bringing things to scale or

Matt

Yes... So I think ultimately, I think there's a few short term impacts. And one is that we hope that, one, some of these micro particles that are being developed end up in commercial hands. So even in the shorter term, we've learned a lot. These have been a really effective research tool where we're able to now say, well, what level of touring do we need to target in these live fees? We can run nutrient requirement studies, and we've been able to do that now with a couple of different nutrients. So as a research tool, very helpful. And then those nutrient requirements can then be tailored for specific species or feeding protocols can be tailored for certain species. So there's some kind of immediate application. The slightly longer term is that we're hoping to get some of these micro particles commercialized by working with commercial partners and get them into the hands of the hatcheries so that they can improve their feeding techniques and technologies. And then in the long run what I'd like to see is that we move away from brine shrimp. I think rotifers would be a little lofty of a goal in my career. Who knows I guess but if we can develop microparticles that at least has a significant reduction of that brine shrimp phase that would be great for both the hatcheries and for globally. A huge amount of the aquaculture industry is really reliant on the Great Salt Lake for archemia. I mean that's where the majority of that's still coming from and it's kind of scary to have such a large dependence on one natural resource and they are doing some good things to make sure that fishery is very sustainable in the long run kind of protecting the Great Salt Lake through a variety of means but to be able to move away from that and allow the industry to grow without that reliance would be a big thing that I hope to accomplish in the longer run and plus that would let hatcheries. They wouldn't need this huge live feeds department; they could employ those people to do other things.

Corinne

That's awesome. I think that's a pretty good wrap up point. Actually, I do have one or two more questions. Do you yourself eat California yellow tail.

Matt

Oh, yeah. No. I love Sushi. Broadly speaking, I wish I ate it more. I haven't found my Go to sushi place. I've only been in Maine for about a year and a half, so but it is like if you haven't had hamachi or kunpachi, I highly recommend it, like, kind of a fattier marine fish. Anyway, it's really nice. I like it where it's just on a little simple bed of rice.

Corinne

Great. You passed the test. That was the correct answer.

Matt

Oh, yeah. Okay, good.

Corinne

Matt's also a mountain biker, so my next question is not Aquaculture related, but what is your favorite kind of mountain bike?

Matt

I kind of joke sometimes. I'll probably never own exactly the car. If you can imagine buying your dream car, you'll probably never get that. But I have exactly the bike. I have a Trek remedy. 27 five. And I love it. It's awesome. It's so fun. It does everything I can do, and it's made me a better rider. And I have, like, a lot of fun. Just if I want to drop off a rock, it drops off rocks. If I want to jump over something, it jumps over something. And then if you just want to go for a light pedal, it's really an efficient peddler, which I like pedaling. I actually have exactly the bike, and it's Battleship blue, which, if you knew my favorite color, it's Battleship blue.

Corinne

Battleship Blue. That's awesome. Well, now it is. Amazing. Great. Well, thank you for taking time to be on the podcast and talk a little bit about Larval. Nutrition and swim fish a lot of people don't even think about.

Matt

Yeah. Well, that's great. Thanks for getting on people's radars and some new topics for them to consider. I think it's important work, and I really enjoy the day. Good luck.

Corinne

Thank you.