The Future of Aquaculture: Creating a Resilient Industry through Nutrition

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Aquaculture is growing rapidly and within the next decade, over half of the world’s seafood will be farmed. A major challenge in the industry is making sure that fish are provided with adequate nutrition to yield a healthy nutritional source for humans while ensuring minimal negative impacts on the environment.

Mission: Climate Change Adaptation & Resilience

Rhys Waters 0:00

Welcome to Beyond Research. A podcast brought to you by Research Nova Scotia.

Stephanie Reid 0:08

Aquaculture is growing rapidly. Within the next decade over half of the world’s seafood will be farmed. A major challenge in the industry is making sure that fish are provided with adequate nutrition to the healthy nutritional source for humans, while ensuring minimal negative impacts on the environment.

Dr. Stefanie Colombo 0:29

You know, my goal is to improve the sustainable production and what that breaks down to meaning is that we can continually produce seafood and a great nutritional source for us without taking advantage or depleting other resources.

Stephanie Reid 0:46

This is Dr. Stefanie Colombo, Canada Research Chair and aquaculture nutrition and an assistant professor at Dalhousie University’s agricultural campus. Today you’ll hear how her research aims to discover novel solutions and nutrition to improve agriculture and contribute toward healthier, environmentally sustainable, and economically viable farms seafood. aquaculture goes by many names Aqua farming, fish farming, I’m sure you’ve heard them all at this point. How would you define aquaculture and what attracted you specifically to this field of research?

Dr. Stefanie Colombo 1:23

So to me, aquaculture is agriculture, except we’re farming seafood. So we’re farming the sea. It’s pretty simple as that. What drew me to aquaculture while I was always fascinated and really drawn to the ocean, as long as I can remember. So I always had this fascination and just felt passionate about it and close to the ocean somehow, even though I grew up in Ontario. But my background is in marine biology. I have an undergrad degree in marine and freshwater biology. So it was kind of natural that I was thinking about ocean conservation and then realizing that we depend on the ocean as a source of food. So how can those two things coexist? And I feel very passionate that you know, we can’t have we can’t achieve food security and ocean conservation without aquaculture in our future.

Stephanie Reid 2:20

So you’re not actually here in Halifax at Dal, you’re at the Dalhousie agriculture campus in Truro. Can you tell us a little bit about your aquaculture nutrition lab?

Dr. Stefanie Colombo 2:31

Mm hmm. So the the lab itself has kind of two main areas. And we have lots of different tanks. And they’re not, you know, small fish tanks that you see at home or at the pet store at an aquarium. They’re really large tanks that have you know, up to 1000 liters each tank. And that allows us to grow different species of fish, either marine and freshwater, and different sizes of fish. We have rainbow trout, Atlantic salmon, arctic char striped bass, and we’re growing them all and doing different types of testing. For me, that means feeding them different diets, for example. And the goal that we’re all working towards is to achieve sustainability and aquaculture improving production, improving efficiency. And all while doing this through a nutritional focus.

Stephanie Reid 3:28

You’re investigating some major challenges facing the aquaculture industry, but looking at it through that nutrition lens. Can you elaborate a little bit on what that means?

Dr. Stefanie Colombo 3:38

Yeah. So nutrition for me is paramount because for two reasons. One is that you can’t have healthy fish without providing them proper nutrition. Simple fact. So you need healthy fish and eat healthy diets. And the second reason why it’s super important is that the whole reason why we’re growing fish is for food. And so having a healthy nutritional source for us humans is important.

Stephanie Reid 4:08

And I was interested to kind of read a little bit about what you’re looking at in regards to fish meal and oil from feeds. And why is it so important that we find alternatives to things like fish meal and oil from feeds? Hmm.

Dr. Stefanie Colombo 4:21

So I guess for the benefit of the listeners that don’t know what fish eat basically what it looks like is a dog kibble like a pellet. It looks like your dog’s food or your cat food. And it’s made in the same kind of way that your corn pops are made from extrusion. That’s basically what it looks like. That’s how pet food is made. So the ingredients that go into making those pellets for fish traditionally have been from wild fish so they harvest wild fish and the main species or the fisheries that they harvest from are things like sardines and anchovies, really small fish they harvest them, and they produce fish meal and fish oil, so protein and fat. And those are the main ingredients that used to go into making salmon food. And you know, that’s not very sustainable, both environmentally because we’re harvesting wild fish stocks to then grow more fish that we’d like to eat. And economically, because these resources are limited is becoming expensive and also unreliable. So for the industry to sustain themselves, you can’t really rely on using wild fish anymore. And so, you know, really, aquaculture has gone away from using a lot of fish meal and fish oil, they’ve reduced it a lot over the years. So the diets now in 2020, than they were even 10 years ago and 2010 look a lot different, they’re a lot more plant based now. So that’s part of the innovation of, of becoming more sustainable is getting away from using fish meal and fish oil out of necessity, really, and and so now there’s even more of an evolution toward other ingredients that don’t depend on some of the resources that we use. So we eat plants, that’s food for us. So instead of feeding fish plants that we could be eating, there are some new innovations that we’re looking at in my lab to kind of get away from using plants and using other sources of nutrients that are better for the fish, and also more environmentally sustainable, like insect proteins and micro algae and microbial sources. And a lot of these ingredients are upcycled. So they use waste from other industries so that you can grow really good nutrients, and then the fish can eat them.

Stephanie Reid 6:47

And just continuing on this same thread. A significant part of your researcher, or your research rather, is centered around something called omega three long chain poly unsaturated fatty acids. Nice. Nailed it. Yeah. And can you tell us about this area in your research and its role in the greater aquaculture picture?

Dr. Stefanie Colombo 7:09

Yeah, so these two omega three fatty acids that are super important, they’re called EPA and DHA. And they’re long chain polyunsaturated fatty acids, you did it so much, instead of like a million times. But these are critically important for all vertebrate animals, we need them, fish need them. And so they are two extremely important fatty acids. And so the reason why they’re important is for for two reasons. So EPA is critically involved in anti inflammation, and hasn’t really important role in our cardiovascular health. And tha is important in in neurological development, and the health and functioning of our brain, there’s so much piling evidence that shows that DJ is important for young children to eat, because it affects their mental capacity later. Anyway, so we need these two fatty acids. And we don’t make them very well, neither do fish. So fish need them in their diet, we need them in our diet. So fish, we’re getting them in their diet from eating fish meal and fish oil from the pellets. So that’s a problem. If we’re removing fish meal and fish oil for sustainability reasons. Where are they going to get the epmd? Ha from? And so that’s been a driving question in my research is, you know, how are we going to supply them with the omega threes that they need if it’s not coming from fish oil, so I’ve come at this from two angles. One is looking at new nutrient sources that are not fish meal and fish oil that can supply them. So micro algae is a great example of that. And some microbial oils are a great example of that. So we’re just testing those now. And the other angle that we’re coming up with is, you know, we know that salmon can make some of their own EPA and DHS just not that great. But is there a way that we can try to enhance that natural capability through selective breeding? And everyone knows selective breeding. That’s how we have Golden Retrievers, and golden doodles like that’s not what dogs looked like. It’s not something that’s unnatural. It’s just we know that they have some of those traits, how can we enhance that traits that they’re doing it instead of a rate of 25%. They’re making it 100%. So we don’t need to put it in their diet. So those are a couple of innovations that we’re working on in my lab right now so that we don’t need to use any fish oil at all.

Stephanie Reid 9:46

In your in testing right now. You mentioned Do you have any results to share at this point or preliminary findings?

Dr. Stefanie Colombo 9:52

Yeah, so as part of the work that I’m doing with the ocean frontier Institute, we looked at a couple of different microbial sources, and they’re actually micro algae. But technically taxonomically we they’re microbes, not exactly micro algae, but they’re single celled organisms that are naturally in the ocean. And a couple of companies that we’ve worked with, they are producing this on a larger scale, and they’re selling the products in different like human nutraceuticals. And now we’re testing it in fish. And what we found is that you don’t need fish meal and fish oil at all. If you use these microbial sources in replacement, and the fish are healthy, they actually have a better, fatty acid profile in the fillets for us to eat as well.

Stephanie Reid 10:42

Oh, wow. Well, congratulations on that. That’s been really exciting.

Dr. Stefanie Colombo 10:45

Yeah, we actually just are about to submit one of our first papers to a scientific journal for that work. Yeah.

Stephanie Reid 10:54

Right. Now you’re doing some interesting research that started either just before or just after the pandemic started in March. around climate change. Do you want to talk a little bit about that one?

Dr. Stefanie Colombo 11:04

Yeah, so some of my previous research has shown that the natural production of omega three fatty acids in aquatic ecosystems, freshwater Marine, will decrease or has a very high probability of decreasing with higher temperatures, because we know that global warming is causing increasing temperatures, we’re already seeing some of these effects and in a negative way, it’s already coming to fruition. Temperature spikes that are happening in early fall No, don’t note only as the temperature goes to getting up to like 23 degrees, which is out of the range for salmon that we grow, the oxygen decreases. So with those two things together, it challenges the survival of salmon in C patents. So this is this is a problem that needs to be addressed. And we’re trying to produce food, but also from natural ecosystem perspective. If we know that wild salmon are faced with a nutritional deficit of omega threes, coupled with an increase in temperature, what does that mean for their survival as well, one of the ways that we’re looking at this in my lab is how can we prepare the fish nutritionally, to better handle situations that they’re faced with with spikes in the temperature and low oxygen. So changing the fatty acid profile in the diet, kind of manipulating their inflammatory system may prepare them to survive those kind of spikes in temperature that global warming is causing, and that we’re going to see more of.

Stephanie Reid 12:39

What are your future research goals and aspirations for the Nova Scotia aquaculture industry as a whole?

Dr. Stefanie Colombo 12:52

There’s so many things. Our seafood is really so important, and not only supplying seafood for ourselves in the Atlantic region, but it’s going around the world. So it’s not only, you know, US realizing the potential that we we sit on this, this resource and our new innovations to supply food, but also, I guess, the the power of that, and the potential for economic prosperity, you know, I’m looking at these some of these new ingredients like insect meals and microbial sources, I want to see those use commercially, that would be a success for me, so that, you know, Nova Scotia is a producer of this insect meal, and they’re supplying it to the world like, that would be amazing for Nova Scotia. And not only that, you know, I’m working on other things like functional ingredients, like prebiotics, for example. And the prebiotics can help improve the gut health of salmon. And when their gut health is improved, they grow faster. So I’m just sort of on the brink of some of these discoveries. And it’s really exciting because I can see some of these things being used commercially, which would really help the industry and then, you know, if they’re developed here in Nova Scotia, it puts us on the mark, as, you know, a high Innovator of these aquaculture solutions.

Stephanie Reid 14:14

How would you describe the state of aquaculture right now here in Nova Scotia?

Dr. Stefanie Colombo 14:20

I think the views of aquaculture have changed when I first came to Nova Scotia in 2006, and a much more positive light in this province and I think just in general around the world, I think people realize that this is the only way that we’re going to be able to produce healthy protein while also ensuring that our wild fish stocks remain in check for healthy ocean. It’s the only way and there’s a huge opportunity for Nova Scotia to kind of latch on to the aquaculture industry to become you know, their own self sustaining source of seafood not only within the Atlantic region but also Canada. And I think what we’ve seen with the pandemic more than more than ever before is that our ability to produce food is so important and paramount to our own survival. And so Nova Scotia has this opportunity where we can provide our own food from this resource from our aquatic resource. And it’s, I can only see it go up from here.

Stephanie Reid 15:26

Well, thank you so much for joining us today, Stefanie. We really appreciate it.

Dr. Stefanie Colombo 15:29

Thanks for having me.

Rhys Waters 15:31

To find out more about this podcast and the research featured in this episode, visit My name is Rhys Waters and we will see you next time.

Dr. Stefanie Colombo is an assistant professor at Dalhousie University’s Agricultural Campus and the Canada Research Chair in Aquaculture Nutrition. Her research team is working to discover novel solutions in nutrition to improve aquaculture and contribute toward healthier, environmentally sustainable, and economically viable farmed seafood.