February 15-18, 2009 Washington State Convention Center Seattle ...

EVALUATION OF SOLVENT EXTRACTED, DEHULLED SOYBEAN MEAL FED IN
PRACTICAL DIETS TO LARGEMOUTH BASS Micropterus salmoides
William DeBoer*, Jeffery Weber, Bruce Cooper and Paul Brown
Department of Forestry and Natural Resources
Purdue University
West Lafayette, IN 47907 USA
wdeboer@purdue.edu
The purpose of this study was to evaluate the effects of graded levels of soybean meal in practical diets fed to largemouth bass
Micropterus salmoides. Solvent extracted, dehulled soybean meal was substituted into the diets for an isonitrogenous amount
of fish meal. Soybean meal concentrations were in increments of 10% of the diet and ranged from 0 to 60 %. Ten fish were
stocked into each of 21 tanks and held at 25 o C. Triplicate groups were randomly assigned one of seven different dietary treatments.
Each tank was fed to satiation twice daily for 8 weaeks. At the end of the study, fish were euthanized, and serum,
muscle, liver, and intestines from three fish per tank were collected and immediately flash frozen in liquid nitrogen and stored
in a -80 o C freezer. The corresponding tissue and serum samples were then used for metabolomic profiling. Additional intestine
samples were preserved in 10% neutral buffered formalin for histological examination.
Mean consumption of diet 1 (0% SBM) was significantly higher than diet 4 (30% SBM). There were no other significant differences
among consumption values. Weight gain of fish fed diets 2 and 3 (10 and 20% SBM respectively) were significantly
higher than in fish fed diet 4 (30 % SBM), but there were no other significant difference among treatments. Hepatosomatic
index of fish fed diet 2 (10% SBM) was significantly higher than fish fed diet 4 (30% SBM) and diet 5 (40% SBM). Feed
conversion ratio, specific growth rate, and visceral fat index were not statistically significant among treatments. Results of the
data indicate that largemouth bass can tolerate high levels of soybean meal in practical diets.