Roberto Bermúdez: «The challenge of aquaculture is to be sustainable»
Any path begins with a first step. And those of Campus Terra in aquaculture, a sector of critical importance for Galicia, were led by Roberto Bermúdez Pose. His was one of the first doctoral theses defended at the Faculty of Veterinary Medicine related to this discipline. In it, he delved into an area as decisive as turbot myxoporidosis, one of the diseases that most affect one of the starfish of the Galician aquaculture industry.
After obtaining his doctorate in Veterinary Medicine from the University of Santiago de Compostela and a diploma from the European College of Aquatic Animal Health (EBVS), he worked in countries such as Australia and Italy. But Bermúdez, who declares himself a staunch lover of Galicia, has always returned to the classrooms where he studied.
Now, he is on the other side of the table as a professor of Veterinary Medicine and the Interuniversity Master's Degree in Aquaculture. He combines this work with his research at GAPAVET, where he focuses on areas such as studying different diseases in farmed fish or developing nutraceuticals.
On Fridays, Roberto Bermúdez swaps his lab coat for neoprene. For him, there is no better way to disconnect from the routine and feel free than surfing, getting lost in the mountains or walking along the Costa da Morte, where his family is from.
Today, we talked to him about his current research and its impact on areas such as food safety, the sustainability of the aquaculture industry and animal welfare.
-You holds a PhD cum laude in Veterinary Medicine from the University of Santiago de Compostela and focused your thesis on the immune response and therapeutic options to deal with enteric myxosporidiosis in turbot. What were the main contributions?
-The problem we studied is turbot myxosporidiosis, a parasitic disease. Typically, parasitic diseases have fairly limited mortality or virulence, except for salmon louse, which in Norway and other countries causes serious havoc in aquaculture production.
Myxosporidiosis in horses was first detected in 1998. The cause was found to be a parasite that was still unidentified. The parasite's importance lay in its somewhat atypical behavior: It annihilated the fish it infected and infected all fish.
The disease began to be called sunken head syndrome because those fish stopped eating and became very thin. Thus, the turbot's eyes sunk (enophthalmia in scientific terms), and the prominences and bones of the skull were marked.
It is a problem because it takes two years from when the fish leave the incubator until they are fattened, and you can take a turbot to commercial size, half a kilo. It is a tremendous investment, and those family businesses without strong economic support went down the drain. You must maintain your production from one day to the next. The big companies, such as Insuiña and Stolt Sea Farm, mainly survived.
-This was one of your first projects with the Veterinary Pathology Pathology Group (GAPAVET).
-We are a group of veterinary pathologists. I was working on a veterinary pathologist project then; at the end of my degree, I was unsure what to do. But it was clear that I didn't want to go into the business world to work as a clinician.
The acronym GAPAVET came later. The group did not change, but the subject we worked on changed. At that time, we were mainly studying terrestrial animals, and then we leaped into the world of aquaculture.
We are a group closely linked to what the business world demands. Things attributed to the university, such as being detached from reality, do not happen in our case. We are in close contact with several companies and institutions of the Galician productive sector, which allows us to understand its reality and try to respond to the problems that arise.
-And how did your thesis help to contain turbot myxoporidosis?
-In the thesis, we tried many things. One of the first things we tried was antiparasitics. We tried a few, but none of them worked. Just as in salmon louse, a copepod that anchors on the outer surface of salmon, these parasites seemed refractory to conventional treatments.
In the case of turbot, the problem was tremendously serious because we did not know the life cycle, the taxonomy, the pathogenesis of the parasite, how it penetrates, how it develops, and what lesions it will produce.... We focused on the parasite and the turbot interaction to learn about the disease and how to tackle it.
None of the treatments we tried stopped the development of the disease. To our knowledge, neither we nor any other group achieved an effective treatment against this parasite.
-So, is it still a threat today?
-It is a threat, but thanks to studies that have been done to understand how it penetrated the host and how it was transmitted, we designed disease control and prophylaxis measures. It is still a threat, but it is not as serious a problem as it used to be.
Now, if it is detected, you know how to act: the batch is blocked so there can be no transmission, neither with materials nor water, between different batches, in addition to taking disinfection and control measures.
The studies we carried out on the pathogenesis of the disease were fundamental to understanding the development of this parasite in turbot and to designing and optimizing control measures to stop it in time.
-You also teach in the veterinary degree program at Campus Terra. What is a typical day like in your job?
-What I like most is that I am still determining what my day will be like. Today, I have class, allowing me to have some order. We teach several core and elective subjects in the veterinary degree, we teach the Master's Degree in Aquaculture, and we are part of several international organizations, such as the European College of Aquatic Health (ECAAH).
These colleges are our means of higher specialization. Once you finish your degree, we do not have an MIR or a specialty. When we finish, we are general veterinarians. One of the many ways we have to specialize is through these colleges: in surgery, aquatic animal health, and diagnostic imaging... Our research group has four members who graduated from this college, which differs from the case in any other faculty in Spain and certainly in a few in Europe.
We must combine all this with research work, supervision of doctoral theses and teaching courses and lectures. For example, last week, I was asked to give a webinar for another specialization school, General Pathologists (ECVP), who wanted to know about the anatomy and histology of fish, which shows a growing interest in this discipline.
-What fish do you focus your current research on, and what diseases or pathogens most affect them?
-I have one fish I hate with all my might: sharks. Because it is tough to diagnose them. We work with exhibitions and ornamental aquariums, but it is the playful and exotic part of our work.
Normally, we work with what the business network demands. In Galicia, the most important fish are turbot and sole, although we also have research lines in trout, eels and zebrafish, for example.
Just as turbot is the most critical fish crop in Galicia, it also forms part of our most potent and long-standing lines of research. In this species, we study myxosporidosis and bacterial diseases such as tenacibaculosis, which causes skin ulcers and makes it impossible to sell affected specimens. We recently requested a project to research furunculosis.
The bacterium Aeromonas salmonicida subs causes this bacterial disease. salmonicida, which causes the misnamed furunculosis. They say it causes furuncles, which are encysted hairs. But fish do not have hair. I guess macroscopically, it looks like skin with encysted hair. This bacterial disease is distributed worldwide and affects many species of fish, mainly salmonids and turbot.
When sole culture was introduced, as it is a flat fish, turbot plants and feed were used. But they have nothing to do with each other; they are of different genera. When we started with sole, the main problem was malformations: more than 50%. It did not influence the quality of the meat, but it caused rejection among consumers. We worked a lot on that, and Ana Manuela de Azevedo and Sonia Vázquez continue to work on it.
We also work with other species, such as the eel, trying to understand the mechanisms that are leading to its disappearance from European rivers. The zebrafish has been emerging for some years as a model species for biomedical research, not only for animal diseases but also those that affect humans, such as glioma or congenital disabilities in glycosylation.
-Why is the use of antibiotics in fish a problem? What consequences could this have on food safety or human health?
-The use of antibiotics in animals is a problem because it generates resistance transmissible within the food chain (through resistance genes) and has repercussions in humans because of the appearance of antibiotic-resistant strains. For this reason, alternative news is being sought, and the use of antibiotics is being reduced.
There is a legal framework for using antibiotics in livestock farming, including aquaculture animal species, which limits the number of antibiotics that can be used in this field because the law does not allow it. On one occasion, Miguel Sotelo, head of pathology in the company BioMar, a member of a tribunal of a thesis that I co-directed, told us that he was tired of hearing that the use of antibiotics in aquaculture was being abused since they were very limited in this sense.
But we must indeed avoid the appearance of antimicrobial resistance at all costs, and as there are antibiotics that cannot be used, we must look for alternatives.
-One of your lines of research focuses on the potential of grape extracts. Could their antimicrobial and antioxidant properties reduce or avoid the use of antibiotics?
-A significant and ambitious project is the European NeoGiANT project, coordinated from Santiago by researcher Marta Lores Aguín. These people realized that grape pomace is an essential residue in wine production. It is used to obtain brandy and as compost, but production is limited.
Grape pomace, like grapes, is a substance very rich in polyphenols, the molecules that give wine or grapes their antioxidant, microbicidal and anticarcinogenic properties, among others. A system was sought to maximize the extraction of polyphenols from the pomace and revalue this waste, turning a problem into a valuable solution.
These things sell themselves and, at the European level, much more. A project of around 9 million euros was obtained, and that is where we came in. One of the activities developed in this project is to investigate, not only in vitro but also in vivo, the effects of administering these substances in different species.
We are going to test it in turbot, trout and zebrafish, the latter in a novel way. Experiments with animals, and especially with production animals such as trout and turbot, require a lot of time, money and effort, both for the design of the experiments and for taking samples and carrying out the different analyses and tests.
Zebrafish is introduced to find out where the shots will be taken. Developing an experimental model allows us to know a little about how this substance will behave when administered orally and by baths and to extrapolate it to commercial species. From the economic and work point of view, it would be unfeasible to do it directly on commercial species.
To test this, we acquired a zebrafish rack, a cabinet in which hundreds of zebrafish are arranged in small aquariums of 3 and 8 liters. This project has allowed us to develop this rack, which will remain for use by other researchers.
Here, polyphenols are extracted from the pomace by different methods. One of the first things to test is that the substances obtained have no harmful effects on living animals. Zebrafish are used for this. We administered the pure substance orally and rectally, and we found that there was no problem with the administration of the pure substance.
In the feed, it will always be in a lower percentage than orally, so it is inferred that very high doses of the product can be incorporated into the feed. Then, we will see the effects of these extracts on the performance of the fish and analyze how they affect their size, weight, coloration, disease resistance... In addition, we will study other parameters such as microbiota composition, immune parameters or blood biochemistry.
-What challenges do aquaculture companies face today, and how can research help overcome them?
-The challenge of aquaculture is to make it sustainable. It is a much more sustainable activity than extractive fishing. However, we also have to realize that there are several critical points to solve, such as species selection or feeding.
Many of the farmed species are being fed with other fish. Most of the flours and oils of animal origin used in fish feed are made with other fish, such as anchovy. These fish are not becoming extinct, but their availability is being alarmingly depleted.
Research lines, such as soybeans, are also being developed to replace animal protein in fish feed. We are immersed in another Next Generation project, with other groups involved in this initiative.
In this project, coordinated by José Luis Soengas from the University of Vigo, the idea is to use discards from extractive fishing, such as blue whiting, and products from fishing industries, such as tuna heads, using these products to replace animal meal partially. In this particular case, in turbot feed.
Antibiotics at the European level are relatively easy. However, we have to realize that the largest aquaculture producers are in Asian countries, and there is not much transparency in the use of antibiotics in those countries. So, those countries do represent a problem.
We will probably have to move towards global legislation, not just for individual countries, and continue to look for alternatives to the use of antibiotics.
Other challenges facing aquaculture are diseases affecting fish and shellfish populations, especially in a globalization scenario and the constant movement of species and pathogens due to climate change. Research can contribute to developing more effective prevention, diagnosis and treatment methods.
-You carried out research stays in Asturias, Barcelona, Italy, and Australia. What did you learn from these experiences, and why did you decide to stay at Campus Terra?
-I learned that you have to go back home. I am a lover of Galicia. I love Lugo; it is a very comfortable city to live in.
Because of the congresses and the stays, you get to know different parts of the world. Although there are really spectacular places, you live very well here. We can have a fairly ideal standard of living, and I don't like big cities at all.
I also won a place at the University of Lleida and gave it up to be here. It was a difficult time for me, the time of the crisis, which is now beginning to change for those who come after me. But our research group here is exciting, and I have always planned to stay here.
-You collaborate with researchers from different universities and countries and participate in European projects. Why is it important to weave these international collaboration networks?
-Above all, because of the funding. That is the most important thing. Access to funding is increasingly difficult and more limited. I don't remember when regional projects ceased to exist, and national projects are difficult to access and very competitive. It is difficult to obtain funding.
Going towards European funding allows access to other funding sources and contact with international research groups. This is constantly enriching because there are different pathologies and different species... And, as in the case of the PhD student Xoel Souto, they allow us to send him to Scotland to study new sequencing or transcriptomic techniques that we can then incorporate into our laboratory and daily work.
-Finally, how did you become interested in veterinary medicine, and when did you decide to focus your professional activity on ichthyopathology?
I was born in Arteixo and came here when I was 17 years old. I didn't have a clear vocation; I always liked animals, but I had other interests, such as drawing fine Arts or writing.
I loved journalism, but it wasn't one of my options.
Physiotherapy was then booming, but it did not give me the note. I entered Psychology, but it was not very appealing because, in those years, there was a lot of unemployment. And in Veterinary, I entered because, fortunately, other people ahead of me quit.
In spite of being one of the last to enter the career, my grades were quite good, so it was quite feasible to obtain funding through the scholarship system. Then, the different research groups were interested in you so that you could join their lines of work. There were several options: surgery, toxicology, infectious diseases, and pathological anatomy.
Maribel Quiroga, who had been my teacher, contacted me and offered me a thesis on the pathology of turbot. I responded in a regular way since the idea of a veterinarian working with fish seemed very strange to me. We laughed about it, and she said it was very cool.
The truth is that later, when you research, it doesn't matter what species you work on because you usually focus on a particular subject.
In this sense, we have an elective in the Anatomy of Fish, Amphibians, Reptiles and Wild Birds. I teach the fish part. I asked the students how many were interested in fish, and they have yet to respond. But when they finish, they realize it is an exciting part of the veterinary world because no veterinarians are trained in this field. We veterinarians are responsible for animal health and, therefore, fish health.
I told them not to close doors, and after a while, those talks awakened some interest in this group of animals.