Master of Science (MS)


Renewable Natural Resources

Document Type



Profitability of aquaculture enterprises worldwide has been affected by rising fish meal prices. Plant proteins are promising replacements for fish meal because of their lower cost and worldwide availability. The goal of this research was to provide nutritional information for the development of all-plant diets for Florida pompano by evaluating growth of fish fed soy-based, fish-meal-free diets and assessing the nutritional value of several plant protein sources. In the first experiment, juvenile Florida pompano were fed five, soy-based, fish-meal-free diets containing graded levels of soybean meal (SBM, or M) at 0, 20, 25, 30, or 35%, with the remaining protein provided by soy protein concentrate (SPC, or C) at 59, 46, 43, 39, or 36%, respectively. These diets were compared to a control diet that contained equal levels (30%) of SBM and SPC in combination with 10% menhaden fish meal. Weight gain of fish fed the control diet (ten times initial weight) was significantly higher than gain of fish fed M0/C59, M20/C46, or M35/C36 diets, but was not different (P > 0.05) from fish fed the M25/C43 or M30/C39 diets. No apparent trends in whole-body composition of pompano were found. Differences in growth appeared to be due to decreased feed intake related to palatability of some diets. Results indicated that fish-meal-free diets that contained 25-30% SBM and 39-43% SPC were as effective as a diet of similar composition containing 10% menhaden fish meal. The second experiment determined apparent digestibility coefficients (ADCs) for canola meal (CM), corn gluten meal (CGM), and distiller’s dried grains with solubles (DDGS). A reference diet and test diets containing 70% reference diet mixture and 30% test ingredient (CM, CGM, or DDGS) were used following typical methods for digestibility trials. Apparent crude protein digestibility of CGM (57.2%) was significantly higher than DDGS (20.6%) but similar to CM (38.6%). Apparent energy digestibility of DDGS (30.7%) was significantly lower than CGM (57.1%) but significantly higher than CM (21.3%). The reference diet formulation was hypothesized to be an additional factor that can influence the calculation of ADCs, in addition to the chemical and physical attributes of the test ingredient.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Reigh, Robert