Feed made from combination of soybean meal and invasive carp meal provides protein for carnivorous aquaculture species without depleting scarcer resources.
COMBINING soybean meal with fish meal made from invasive Asian carp produces a more nutritious, sustainable and economical option for feeding some farm-raised fish, according to recent Southern Illinois University (SIU) research.
Both laboratory and on-farm feeding trial research, funded by the Illinois soybean checkoff, showed that species like hybrid striped bass and largemouth bass can effectively digest greater amounts of soybean meal when blended with meal derived from Asian carp.
"The research may solve several challenges for midwestern fisheries and the aquaculture industry," said Jesse Trushenski, associate professor at the SIU Center for Fisheries Aquaculture & Aquatic Sciences in Carbondale, Ill. "The fish diets we studied use meal from Asian carp, an invasive fish that is spreading and disrupting ecosystems in the Mississippi River Basin. Blending carp meal and soybean meal allowed us to use larger amounts of soybean meal. These diets offer a local alternative to marine-based fish meal."
Aquaculture is an expanding industry that demands protein and needs to develop alternate feed sources, according to Trushenski.
The growing scarcity of wild anchovies and sardines increases the costs of marine-based fish meal and affects ocean ecosystems. Soybean meal is a proven, renewable alternative, but using just soybean meal in place of fish meal affects the growth and health of some carnivorous species, SIU said.
"Previous SIU research established Asian carp meal as equal to or better than marine-based fish meal in aquaculture diets and helped set standards for using soybean meal in aquaculture," Trushenski explained. "We took our understanding of protein for carnivorous fish feed a step further by demonstrating synergies between local protein sources: soybeans and invasive fish."
The research trial formulations used 25% soybean meal and 18% Asian carp meal — proteins readily available in the Midwest. A new carp rendering plant in Grafton, Ill., will boost the availability of Asian carp meal and demonstrates the ripple effect this solution can have on rural economies.
"Cost-effective carp meal is good news for soybean meal demand in aquaculture," Illinois Soybean Assn. director Duane Dahlman said. "This SIU research proves that the two ingredients can be used together in a nutritious fish feed blend for key species.
"Using Asian carp benefits commercial fishing, and carp meal production creates jobs," Dahlman added. "Plus, feeding local soybean meal and carp meal can improve profitability for fisheries and farmers. All of these industries are based in rural areas that benefit from income, jobs and strengthened tax bases."