Oral vaccines for fish

By TPN/Lusa, in News, Health & Environment · 24-04-2021 08:37:00 · 2 Comments

Researchers from the Interdisciplinary Center for Marine and Environmental Research (CIIMAR) have developed oral vaccines for aquaculture fish that, incorporated in the food, prevent the occurrence of bacterial diseases.

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”.

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The fish farming industry needs radical environmental reform. Bacterial infections are almost exclusively caused by the overcrowding of fish in tanks. Fish were never meant to be industrially farmed; our unnatural demand for cheaper and cheaper food (having almost exhausted wild stocks in the sea through decades of unrestricted overfishing), means that we subject these creatures to conditions that make them (and potentially us) very sick. We know that feeding livestock of any kind antibiotics and other chemicals has a knock-on effect - sometimes very dangerous, when it accumulates in the human body. Farmed fish are already subjected to chemicals to prevent sealice/mites on their scales and other problems due to overcrowding. Unless there are longterm studies of the effects of such vaccines/chemicals, I suggest we all avoid eating these force-fed, overcrowded, diseased and chemically bombarded captives.

By Judith Carol Irwin from Beiras on 25-04-2021 12:25

When will man learn to leave nature alone.
Vaccinated the global population from a virus with a death rate of 0.7% of those infected and now lets go vaccinate fish.
What's wrong with man ?
When will we wake up to this joke on humanity ?

By Roger Bellamy from Lisbon on 24-04-2021 05:31
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