New approach to fish feed

Fish as human food present a unique problem. The protein they provide is high quality and low in fat. People all over the world enjoy fish as a staple of their diet. Unfortunately, the demand for fish has overtaxed natural populations. Regulation has been successful in some areas (Alaskan salmon), yet failed miserably in others (Mediterranean tuna). The big question is: how can humans continue to enjoy eating fish but avoid the extinction of popular species?
Aquaculture is one solution. Farming has been especially successful with vegetarian fish like tilapia and catfish, because they can be fed grain based meal. It hasn’t been as sucessful with carnivorous fish because they require a high protein meal that is typically made from smaller fish like anchovies. Overfishing of the smaller fish has negative effects on wild ecosystems. Researchers at Mississippi State may have found the solution. Feed made from insects contains high quality protein and is cheap to produce. Excerpts from the press release are below the cut.

Aquaculture, the commercial production of seafood in managed ponds or tanks, currently supplies about 46 percent of all seafood consumed in the world today. The United Nations’ Food and Agriculture Organization predicts that commercially grown supplies will rise to 75 percent of consumption in the next 20 years.
“The supply of wild-caught fish has really been flat since the late 1980s, and those stocks have little chance of regaining their past levels because of pollution, overfishing and other factors affecting commercial fishing,” Papadoyianis said. “Aquaculture is left to bridge the widening gap, and we have to be sustainable in all aspects of our industry.”
More than 25 percent of all fish harvested today are used for fish meal, and the majority of fish meal is used to produce other fish, he said. These baitfish stocks, such as anchovies, menhaden and herring, are exploited, and growing scarcer as time goes on. The result is an ever-tightening supply situation, which has caused sharp price increases over the last year. This trend is expected to worsen.
“The first phase of the research was the selection of insect species with high amounts of protein that can be economically produced by the millions,” Davis said.
By early fall the species were selected and feeding trials began with hybrid striped bass supplied by Neptune.
The feeding trials are being conducted by MAFES scientist Lou D’Abramo, who is comparing feed pellets made with fish meal to pellets produced from insects. Both were commercially produced and look identical.
“The early trial results indicate the fish have no real preference for one over the other,” D’Abramo said. “In the wild, fish do come to the surface to feed on dragonflies and other insects, so it makes sense that they will eat pellets made from insects.”
D’Abramo is also studying weight gain and other factors that will determine whether the insect-based diet is acceptable for commercial fish production.
The next phase of the research was conducted at MSU’s Garrison Sensory Evaluation Laboratory to determine whether an insect diet affects the taste, texture or other qualities of the fish.
“Our evaluation of the samples of hybrid striped bass from the feeding trail indicated no difference in appearance, flavor or texture of the fish grown on the insect-based diet and those grown on the fish meal diet,” said Patti Coggins, director of the sensory evaluation lab. “The only difference we found was that the fillets from the fish raised on the insect diet did not have a strong ‘fishy’ smell.”
With research pointing to the potential success of insect-based diets in fish production, Papadoyianis is looking ahead to the next step in the process — construction of a pilot insect-rearing facility to test growing, harvesting and processing methods.
“We’ve already had inquiries from all over the world about this,” Papadoyianis said. “Our vision is to have insect production facilities in all of the geographical regions with major commercial aquaculture industries in order to reduce freight costs. That will require researching the use of local insect species, nutrition and production methods, so we envision a long-term relationship with Mississippi State University.”

I’ve always said that algae and fungi would be the final solution to hunger problems as we move into the future. I may have to add insects to the list!

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