Infections caused by parasites, bacteria, and viruses have become one of the major challenges in the aquaculture industry. These pathogens can have devastating effects on aquaculture operations, leading to economic losses and environmental concerns. While traditional methods such as vaccination and antimicrobial treatments have been used to combat these infections, they are often insufficient. The excessive use of antimicrobials has raised concerns about antibiotic resistance and negative environmental impacts.
In recent years, probiotics have emerged as a promising alternative to enhance the immune system of aquatic organisms and combat pathogens. Some probiotics have been genetically modified to express and deliver immunomodulatory molecules, which can promote selective therapeutic effects and specific immunization against particular pathogens.
A team of researchers from the Autonomous University of Baja California (Mexico), the University of Santiago de Chile, the University of Los Lagos, INRAE, and the Université Paris-Saclay published a scientific review in the journal Microorganisms. They explore the role of probiotics in aquaculture, focusing on their impact on disease treatment and the potential of recombinant probiotics as alternatives to antibiotics.
The Rise of Probiotics in Aquaculture
Probiotics have been shown to modulate the immune system, compete with pathogens for resources, and produce antibacterial substances. They have been used to treat various diseases in fish, including bacterial infections, viral diseases, and parasitic infestations.
Recombinant Probiotics: A Novel Approach
Recombinant probiotics are genetically modified organisms that express and release specific therapeutic molecules. This technology offers several advantages, including:
- Customized Solutions: Genetically modified probiotics can be designed to address specific health challenges in different species and aquaculture environments.
- Enhanced Efficacy: By expressing specific immunomodulatory molecules, genetically modified probiotics can more effectively target and eliminate specific pathogens.
- Reduction of Unwanted Effects: Compared to antibiotics, recombinant probiotics are less likely to disrupt beneficial microbial communities in the fish gut.
- Reduced Environmental Impact: The use of genetically modified probiotics can potentially reduce the need for antimicrobial treatments, thus minimizing their environmental impact.
Applications of Probiotics and Recombinant Probiotics in Aquaculture
- Bacterial Infections: Probiotics can help prevent and treat bacterial infections, such as those caused by Aeromonas, Vibrio, and Streptococcus.
- Viral Diseases: Probiotics can enhance the immune response to viral infections, including viral hemorrhagic septicemia and infectious pancreatic necrosis.
- Parasitic Infections: Probiotics can reduce the prevalence of parasitic infections, such as those caused by Ichthyophthirius multifiliis and Gyrodactylus spp.
Barriers to Widespread Adoption
Despite the potential benefits of genetically modified probiotics, several barriers hinder their widespread application in aquaculture:
- Regulatory Hurdles: The development and commercialization of genetically modified organisms (GMOs) often face stringent regulatory requirements, which can be time-consuming and costly.
- Consumer Acceptance: There may be concerns among consumers about the safety and efficacy of genetically modified organisms, particularly in food products.
- Technical Challenges: The development of genetically modified probiotics requires specialized expertise and infrastructure.
Recent Research and Future Directions
According to the study, recent research has demonstrated the potential of genetically modified probiotics in aquaculture. For example, studies have shown that genetically modified probiotics can enhance the immune response of fish to viral infections and reduce the severity of the disease.
Future research should focus on:
- Developing genetically modified probiotics that target specific pathogens and provide effective protection.
- Addressing regulatory concerns and ensuring the safety and efficacy of these organisms.
- Increasing awareness and acceptance of genetically modified probiotics among consumers.
- Exploring the potential of genetically modified probiotics for other applications in aquaculture, such as improving feed efficiency and reducing stress.
Conclusion
Genetically modified probiotics offer a promising solution to the challenges faced by the aquaculture industry. By enhancing the immune response of aquatic organisms and reducing dependence on antimicrobial treatments, these microorganisms can contribute to a more sustainable and profitable aquaculture sector. However, overcoming regulatory hurdles and addressing consumer concerns will be essential for the widespread adoption of genetically modified probiotics in aquaculture.
Reference (open access)
Torres-Maravilla, E.; Parra, M.; Maisey, K.; Vargas, R.A.; Cabezas-Cruz, A.; Gonzalez, A.; Tello, M.; Bermúdez-Humarán, L.G. Importance of Probiotics in Fish Aquaculture: Towards the Identification and Design of Novel Probiotics. Microorganisms 2024, 12, 626. https://doi.org/10.3390/microorganisms12030626
