Aquaculture system changes influence soybean use

Filtration systems may support greater soybean meal use in aquaculture feeds.

Recent research results examined how combined ultrafiltration (UF) and reverse osmosis (RO) technologies in a recirculating aquaculture system (RAS) can increase soy protein use in aquaculture feeds, according to an announcement from the Soy Aquaculture Alliance (SAA).

During the 2018 study conducted by SAA and Prairie AquaTech LLC, two separate feeding trials were conducted using tank-based RAS and rainbow trout.

"Our hope when working with Prairie AquaTech on this research was to understand how various system changes can impact diet reactions in farm-raised fish," SAA executive director Andy Tauer said. "We know there are lots of new technologies out there, and if we can find a way to increase soybean meal based on a system change, then our research funds are well spent."

The first trial assessed fish at increasing densities using conventional water technologies with a diet of 13% fish meal and no soybean meal. The second trial utilized UF/RO systems with a diet of very high soybean meal concentration (40%).

According to the announcement, results showed that, when paired with UF/RO systems, diets that included soybean meal increased trialed fish bodyweight and reduced mortalities. In future trials, diets containing 20% soybean meal are hypothesized to yield more consistent average bodyweight compared to fish meal, SAA suggested.

"Prairie AquaTech was happy with these results, and we believe there is value to trial varying inclusion rates and see an even greater return on investment," Tauer added.

SAA works to create new opportunities for soybean farmers within the growing domestic aquaculture market. SAA funds programs and research that increase the utilization of U.S. soybeans in the diets of fish and shrimp through affiliations with academic and private researchers and industry leaders.