US – Researchers at Oregon State University have developed a new technology to deliver water-soluble nutrients to aquaculture-raised fish, oysters, clams and shrimp that will boost their growth rates and reduce the high rates of mortality that plague the industry.

According to scientists, the study on aquaculture was important because the US has a major seafood deficit, importing more than U$11 billion of seafood products annually from other countries.

Chris Langdon, a professor of fisheries at OSU’s Hatfield Marine Science Center and principal investigator on the project noted that aquaculture will be critical in the future to produce protein for the world’s growing population because many wild stocks of fish have already reached their peak levels of sustainable harvest.

“We’re having some success by packaging water-soluble nutrients into liposomes that we use to enrich the live feeds – for example, brine shrimp – or put inside of food pellets,” Langdon said.

“The next step is to expand the project and look at how it affects different fish species, and whether we can make it cost-effective.”

The key to the preliminary success by the OSU scientists, which include post-doctoral researcher Matt Hawkyard, lies in the production of liposomes, which are tiny vesicles, or bubbles, made out of the same material as a cell membrane.

These liposomes are very efficient in containing nutrients, and other products, despite their small size, which over the past five to six years, OSU researchers have incorporated liposomes that are filled with nutrients.

“We also can fill the liposomes with other substances, such as growth-promoting agents, vaccines, or vitamins to boost the animals’ immune systems and reduce stress,” Langdon added.

“In addition to aquaculture for food species, there is a potentially huge opportunity to improve the survival and health of ornamental fish for the aquarium industry that is worth billions of dollars.”

Langdon and Hawkyard are working with the Hubbs-SeaWorld Research Institute in San Diego to broaden the scope of their study, focusing on improving growth rates and reducing losses in California yellowtail, sea bass and ornamental fish.