ABSTRACT
We compared the benefits of using extruded feed (EF), against pelleted feed (PF) to guide cage culture investments in Great Lakes. Three out of six cages in the same farm had fish that were fed EF and the other half, belonging to a different farm had fish that were fed PF. The diets were similar in crude protein, lipid and energy content. However, the fiber content in PF was 4 times higher than that of EF. The fish fed on EF grew better (438.0 ± 7.4 g) than the fish fed on PF (220.8 ± 2.9 g). The cost of production for EF was about 26% lower than for PF, primarily because of better feed utilization. The load of P and N for PF diet was 59% and 29% higher, respectively, than when EF was used. Therefore, EF feed delivered better economic gains with lower environmental impact than PF feed.
Acknowledgments
This study was funded by the GRO Fisheries Training Programme, a UNESCO Category 2 Centre in Iceland in collaboration with Kenya Marine and Fisheries Research Institute (KMFRI). Helgi Thorarensen was a visiting scholar at the University of South Eastern Norway while working on the manuscript. We thank Dr. Linda May, UKCEH, for improving the English of the manuscript.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Ethical approval
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed by the authors.