Aquaculture is the main source to increase fish supply. Fast development of aquaculture and increasing fish demand
lead to intensification of fish culture, magnifying stressors for fish and thus heightening the risk of disease.
Until now, chemotherapy has been widely used to prevent and treat disease outbreaks, although use of chemical
drugs has multiple negative impacts on environment and human health e.g. resistant bacterial strains and residual
accumulation in tissue. Hence, disease management in aquaculture should concentrate on environmentally
friendly and lasting methods. Recently, increasing attention is being paid to the use of plant products for disease
control in aquaculture as an alternative to chemical treatments. Plant products have been reported to stimulate
appetite and promoteweight gain, to act as immunostimulant and to have antibacterial and anti-parasitic (virus,
protozoans, monogeneans) properties in fish and shellfish aquaculture due to active molecules such as alkaloids,
terpenoids, saponins and flavonoids. However, as it is a relatively emerging practice there is still little knowledge
on the long-term effects of plant extracts on fish physiology as well as a lack of homogenization in the extract
preparation and fish administration of the plant extracts. This article aims to review the studies carried out on
the use of plant products on fish aquaculture and their biological effects on fish such as growth promoter,
immunostimulant, antibacterial and anti-parasitic. It also intends to evaluate the current state of the art, the
methods used and the problems encountered in their application to the aquaculture industry.