Probiotics improve health of farmed European seabass

Study found significant improvements in the immune response and greater survival in challenges against Vibrio anguillarum in fish fed with probiotics.

2_Estudiante de doctorado Luis Monzon
PhD student Luis Monzón at ECOAQUA Institute
May 21, 2024

A study led by the Aquaculture Research Group (GIA), from the ECOAQUA Institute of the University of Las Palmas de Gran Canaria (ULPGC), has revealed how the use of certain probiotics (specifically, Bacillus velezensis) in European seabass leads to a significant reduction in the incidence of diseases, which translates into an improvement in productivity.

Researchers fed seabass with a diet supplemented with this probiotic to evaluate immunological parameters and perform disease challenges with common pathogens. Results showed significant improvements in the immune response of the treated fish as well as greater survival in challenges against Vibrio anguillarum.

In the first phase of the research, supplementation of the seabass diet with Bacillus velezensis strain D-18 was carried out in order to evaluate various immunological parameters. These analyses already revealed a significant improvement in all the parameters measured in the fish that received the probiotic diet, such as innate humoral and cellular mechanisms.

The scientists then subjected fish fed with and without the probiotic-supplemented diet to a challenge against Vibrio anguillarum. Researchers found greater survival against the pathogen in those fish that were fed with the probiotic, a significant increase in immunological and lytic activities, as well as an improvement in the expression of genes related to the immune response.

The study, directed by the professor in animal health, Félix Acosta, has obtained the recognition of Most relevant work of 2023 by the Aquaculture Business Association of Spain (APROMAR).


Luis Monzón-Atienza, Jimena Bravo, Álvaro Fernández-Montero, Ives Charlie-Silva, Daniel Montero, José Ramos-Vivas, Jorge Galindo-Villegas, Félix Acosta. Dietary supplementation of Bacillus velezensis improves Vibrio anguillarum clearance in European sea bass by activating essential innate immune mechanisms, Fish & Shellfish Immunology, Volume 124, 2022, Pages 244-253