Natural Alternatives in Aquaculture

Intensive fish farming has spread of several bacterial diseases over the years and as a solution more antimicrobials (antibiotics and drugs) are used. The negative consequences of antibiotic use on public health have encouraged the development of strict regulations controlling the use of antibiotics and other drugs. The high numbers of antibiotic-resistant bacteria because of antibiotic usage provides a threat to aquaculture as they become the source of the antibiotic resistant gene that stays in the culture.

Bacterial antibiotic resistance and antibiotic residues has become a matter of concern across the globe, there is a need to develop alternatives to deal with for bacterial pathogens in aquaculture.

Several alternatives to the use of antibiotics have been used successfully in aquaculture. The use of probiotics or friendly bacteria to avoid pathogenic infections in aquatic organisms has been tested in aquaculture.

Several microorganisms has been tested and used as probiotics in aquaculture research. The most studied are species of lactic acid bacteria , Bacillus, Pseudomonas, Aeromonas, yeasts, Acinobacter… These probiotics have been used in different aquatic organisms and have been shown to be successful, not only for their ability to prevent disease, but also for improving digestion and growth. Many of these applications have been targeted at the early stages of development of the aquatic organisms, such as the larval stages, because these stages are more susceptible to infections.

Some of the proposed mechanisms that provide protection against pathogens involve the production of inhibitory compounds, competition for essential nutrients and adhesion sites, the enhancement of disease resistance and the modulation of host immune responses.

Another alternative treatment is using natural essential oils and herbal extracts, which are natural components from plants that are generally recognized as safe substances (GRAS). Due to their antimicrobial properties, these natural products may constitute alternative prophylactic and therapeutic agents in aquaculture.

There is still a lot of research going on and huge scope of development in the area of natural substitutes to increase productivity with sustainable environment for Aquaculture. To reduce antibiotic use in aquaculture best practices are to minimize the level of stress on the fish and reduce the chance of infections requiring antibiotics treatment.