The study conducted by researchers from the Aquaculture Research Group (GIA) at the ULPGC university institute, in collaboration with scientists from the Italian university, under the direction of Dr. Félix Acosta Arbelo, confirms that the probiotic Bacillus velezensis D-18 helps sea bass to better resist disease and reduces the need for antibiotics
This scientific finding increases survival rates and improves the intestinal health of this marine species, serving as a clear example of applied science for safer aquaculture in the service of marine conservation and sustainable production
An international team of researchers from the Aquaculture Research Group (GIA) at the ECOAQUA University Institute of the University of Las Palmas de Gran Canaria (ULPGC) and the University of Bologna (Italy) has demonstrated that the probiotic Bacillus velezensis D-18 significantly improves the health and survival of European sea bass (Dicentrarchus labrax) against the emerging pathogen Vibrio harveyi, one of the most problematic bacteria for Mediterranean aquaculture.
The study, led by Professor of Animal Health in Aquaculture, Dr. Félix Acosta Arbelo, entitled 'Effects of Bacillus Velezensis D-18 on Health Status of European Seabass (Dicentrarchus labrax) Experimentally Challenged with Vibrio harveyi', has recently been published in the prestigious scientific journal ‘Probiotics and Antimicrobial Proteins (Springer Nature)’, representing a key advance in the search for sustainable alternatives to the use of antibiotics in aquaculture.
Proven protective effect
During the trial, the fish were fed for 30 days with a diet supplemented with the probiotic Bacillus velezensis D-18, previously isolated and characterized by the GIA group team. The animals were then experimentally exposed to Vibrio harveyi.
The results of the research were conclusive. On the one hand, survival increased from 27% to 50% in fish that received the probiotic. In addition, histological improvements were observed in the intestinal mucosa, including a larger villous area and an increase in the number of goblet cells.
Giorgia Bignami at the facilities of the Specialized Aquaculture and Biotechnology Service (SABE) of the IU-ECOAQUA at the ULPGC. One of the infrastructures of excellence within the European AQUAEXCEL 3.0 project.
On the other hand, the antibacterial activity of the serum increased significantly in the supplemented fish after infection.
Likewise, analysis of the intestinal microbiome and environmental biofilm showed stability in microbial composition, indicating that the probiotic does not negatively alter the bacterial ecosystem of the fish or the tank.
A real alternative to the use of antibiotics
Dr. Félix Acosta Arbelo highlighted that “the results confirm the potential of Bacillus velezensis D-18 as an effective preventive tool against emerging pathogens in aquaculture, contributing to reducing dependence on antibiotics and promoting more sustainable production systems.”
The study reinforces the strategic line of the GIA group of the ECOAQUA Institute of the ULPGC and the University of Bologna in the development of biotechnological solutions applied to aquaculture health, in line with the sustainability objectives promoted by the Food and Agriculture Organization (FAO) of the UN (United Nations Food and Agriculture Organization) and the ‘Blue Transformation’.
Dr. Luis Monzón Atienza at the facilities of the Specialized Aquaculture and Biotechnology Service (SABE) of the IU-ECOAQUA at the ULPGC.
European benchmark and international collaboration
The work was carried out by a multidisciplinary team from both institutions, combining expertise in microbiology, immunology, histology, and microbiome analysis. The collaboration reinforces the position of the GIA at the ECOAQUA University Institute of the ULPGC as a European benchmark in applied aquaculture research.
Facilities of the PCMT at the ULPGC.
This research was carried out under the auspices of the European project AQUAEXCEL 3.0, which promotes excellence in European aquaculture, integrating 40 infrastructures of excellence for innovative research with transnational access.
In addition to Félix Acosta Arbelo, the study involved the participation of researchers from the ECOAQUA GIA group Luis Monzón Atienza, Antonio Gómez Mercader, and Pedro Luis Castro Alonso, as well as Giorgia Bignami, Daniela Leuzzi, Daniel Scicchitano, Marco Candela, Andrea Gustinelli, Mouna Jlidi, Perla Tedesco, and María Letizia Fioravanti from the University of Bologna.