Cottonseed could feed trout industry. (Update).
The Ohio State University natural resource researchers recently replaced fish meal protein with cottonseed meal protein in up to 100 percent of male and female rainbow trout's diet. They report finding no difference in growth using the new feed over the old during a nearly three-year test period.
"Organic labeling of some fish species is a hot issue right now," says project researcher Konrad Dabrowski. "... cottonseed meal is an acceptable form of feed in organically raising fish since the main ingredient is plant-based."
"Fish meal costs about $550 a ton, while cottonseed meal is S120 a ton," Dabrowski says. "Food is 50 percent of all costs in aquaculture."
He adds that some species, such as salmon, eat up to 5 pounds of protein for each 1 pound of protein gained.
One limitation that makes using cottonseed meal a challenge is the presence of gossypol, a natural toxin found in the cotton plant for preventing insect damage. Gossypol produces toxic effects in fish species such as tilapia. Rainbow trout is one of the few fish that shows resistance to the toxin.
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|Publication:||Resource: Engineering & Technology for a Sustainable World|
|Article Type:||Brief Article|
|Date:||Feb 1, 2002|
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