2010 Annual Report
Dietary lysine requirement for Pacific threadfin: An 8 wk growth trial was conducted to estimate the Lys requirement based on growth performance. Results showed that the Lys requirement is 1.79% (5.1% protein).
Dietary methionine requirement for Pacific threadfin: Met is limiting amino acids in soy protein, which is widely used to replace fishmeal. An 8 wk feeding trial is ongoing; results will be available Sept.
Optimal dietary protein and energy for Pacific threadfin: An 8 wk growth trial, fed diets containing 25-45% protein at 2 dietary levels (10% and 14%). Diet containing 35% protein and 14% lipid showed the best growth, which was equal to a commercial feed containing 50% protein and 14% lipid.
Optimal feeding rate for juvenile Pacific threadfin: The optimal feeding rate was estimated by a 5 wk trial based on growth performance. The study found optimal feeding rate was 6% of body weight for the 3g juveniles.
Methionine requirement of Pacific white shrimp: 2 feeding trials were conducted to estimate Met requirement of shrimp using crystalline and covalent bound soy protein-Met. The trials at TAMU and OI failed to estimate Met requirement of shrimp.
Identify and characterize regionally based plant and animal co-products as ingredients for aquatic feeds.
Nutrient analyses of Island co-products: 10 island co-products from fish wastes, biofuel oil extraction and cull agricultural products were characterized as potential feed ingredients. Mineral, gross energy, amino acid, fatty acid and carotenoids were analyzed; data will be used to formulate diets.
Digestibility of Hawaiian Island co-products: 3 agricultural co-products: meat & bone meal, macadamia nut cake and spent fruit fly media were tested for their digestibility in Pacific white shrimp. Results showed the ingredients had acceptable digestibility for shrimp diets.
Determination of fatty acid and carotenoid composition for Haematococcus pluvialis and its esterified astaxanthin product (BioAstin®SCE5): The fatty acid profiles of H. pluvialis and its astaxanthin product were determined. They had a low content of docosahexaenoic and eicosapentaenoic, but high content of oleic, linoleic and palmitic acid.
In vitro digestibility of protein ingredients in diets: PH-Stat method was established to determine a quick way of in vitro digestibility of protein ingredients. Eleven protein ingredients were measured by in vivo digestibility and the results will be correlated with in vitro digestibility.
Develop commercially applicable feed processing techniques that optimize economic potential and limit waste.
Two extruder configurations were tested and two particle sizes of ingredients were evaluated for their effect on growth and feed efficiency. Growth performance was not affected by the two extruder configurations and the smaller ingredient size in shrimp feed can improve feed efficiency.
This project is monitored through meetings, conference calls, email communication, and on-site v