Speaking to Lusa, Cláudia Serra, a researcher at the centre of the University of Porto, explained that the project, entitled ProbioVaccine, arose from the need to find solutions to one of the problems of aquaculture: "the frequent existence of bacterial diseases in fish".
"Bacterial diseases, some of which are zoonotic, are very frequent and lead to very significant economic losses because aquaculture production is affected", she said.
According to the researcher, currently, one of the “stratagems” used by the sector to prevent the bacterial disease from setting in is vaccination.
Despite being the “most effective” solution, injectable vaccination causes “complications at the logistical level”, “implies a lot of investment” and has “repercussions” in terms of fish stress.
“Most of the vaccines used in aquaculture are injectable, but from a logistical point of view it is very laborious because the fish are vaccinated one by one, it involves a lot of investment and has repercussions on the level of fish stress. Fish are very susceptible to stress and do not like to be handled, nor to be out of water”, said Cláudia Serra.
In this sense, CIIMAR researchers have developed an oral vaccine that, when incorporated into the feed, prevents the occurrence of bacterial diseases en masse.
Although oral vaccination is not “a novelty in aquaculture”, the one developed by CIIMAR was tested on zebra fish and revealed “promising results” with different pathogens, one of which observed a “reduction in mortality in the order of 50 percent”.