FISH MEAL AS A POTENTIAL END USE OF INVASIVE ASIAN CARP FROM THE ILLINOIS RIVER

Author

John Cory Bowzer, Southern Illinois University CarbondaleFollow

Date of Award

8-1-2014

Degree Name

Doctor of Philosophy

Department

Zoology

First Advisor

Trushenski, Jesse

Abstract

Subsidized harvest of invasive silver carp Hypopthalmichthys molitrix and bighead carp H. nobilis (collectively referred to as Asian carp) from the Illinois River have been initiated in an effort to control their populations. However, market-driven control strategies have been suggested in an effort to reduce or eliminate the need for subsidies. Given that Asian carp are not a favored food fish in the U.S. and exporting to Asian markets is currently not economically feasible, industrial applications such as fish meal production have been explored. Fish meal production to support aquafeed manufacturing is potentially a high-value, high-volume market which is essential to a market-driven approach. However, the nutrient composition of Asian carp as a raw material from the Illinois River needs to be evaluated as well as the nutrient digestibility and production performance of a rendered Asian carp fish meal product to fully assess its suitability for use in aquafeeds. To determine the suitability of Asian carp to support aquafeed manufacturing, we evaluated seasonal and geographical differences in Asian carp harvested from the Illinois River, performed standard digestibility trials with hybrid striped bass and rainbow trout, and assessed production performance through standard feeding trials with hybrid striped bass, rainbow trout, and cobia. Results indicate slight geographical and seasonal variation in body composition, though both species represent protein-dense raw materials suitable for fish meal production. Additionally, Asian carp fish meal is a highly digestible feedstuff that closely resembles the nutrient content of traditional menhaden fish meal sources, although it is slightly less digestible. Production performance of fish fed practical Asian carp fish meal based diets was similar to those that used menhaden fish meal. Overall, Asian carp fish meal appears to be a highly-digestible, nutrient-dense ingredient suitable for inclusion in aquafeeds. Therefore, rendering Asian carp into fish meal appears to be a viable market-driven approach to help control Asian carp populations.