1a. Objectives (from AD-416)
The objectives of this cooperative research project are to: (1) Determine nutrient requirements of target aquatic species and develop viable diet formulations as a foundation for commercial industry development; (2) Identify and characterize regionally based plant and animal co-products as ingredients for aquatic feeds; and, (3) Develop commercially-applicable ingredient and feed processing techniques that optimize economic potential and limit waste.
1b. Approach (from AD-416)
Research will utilize tank and laboratory based trials to define key dietary requirements of Pacific white shrimp and marine fish of local interest (Pacific threadfin and amberjack); and, with PBARC, utilize molecular methods to identify expression sequences applicable to selective breeding and/or genetic modification. Efforts will also target novel and value-added regional plant and animal feedstuffs and waste-stream co-products from the biofuels and rendering industries in diets for target species. This project will also determine nutrient content, functional properties, nutrient digestibility, and attractability of potential ingredients and, with PBARC, identify and overcome anti-nutritional properties of novel ingredients through selective breeding and/or genetic modification. In addition, scale-up grinding, mixing, agglomeration, pre-conditioning, and post-conditioning methods applicable to commercial feed milling operations will be developed. Formerly 5320-31000-007-03G (8/2008). Documents SCA with Oceanic Institute.
3. Progress Report
Because of the limited information concerning the amino acid requirements of the targeted species of Pacific white shrimp (Litopenaeus vannamei) and the marine fish species, Pacific threadfin (Polydactylus sexfilis) and longfin amberjack (Seriola rivoliana), one of our objectives in this project is to define these species amino requirements. Ongoing discussion and cooperation among scientists at the Oceanic Institute (OI), Texas A & M University (TAMU) and the USDA-ARS Pacific Basin Agricultural Research Center (PBARC) have been working, and planning research trials to define these amino acid requirements where diets can be formulated with optimum amino acid profiles for maximum feed efficiency and animal performance. Our collaborative efforts with researchers at TAMU have continued in defining the amino acid methionine requirements of the Pacific white shrimp Litopenaeus vannamei using protein-bound (manufactured at OI) and crystalline sources for determining the requirements for Litopenaeus vannamei. Two studies at TAMU were conducted simultaneously in their recirculation system to evaluate apparent methionine requirement of juvenile Pacific white shrimp. A soy protein-based diet was formulated to be adequate in digestible essential amino acid concentrations with the exception of methionine. Dose-response diets were prepared using a basal diet (25% CP) supplemented with either covalently-bound (Study 1) or crystalline (Study 2) L-methionine. Results showed no significant difference (P>0.05) in survival of shrimp fed dietary treatments within studies. The result in Study 1 (covalently-attached supplementation) an estimated methionine requirement level of 0.45% was suggested. The result in Study 2 (crystalline supplementation), a methionine requirement level of 0.66% was suggested. A publication of the study is in progress; ESTIMATION OF APPARENT METHIONINE REQUIREMENT OF THE PACIFIC WHITE SHRIMP, Litopenaeus vannamei, USING PROTEIN-BOUND AND CRYSTALLINE SOURCES. A validation trial is being conducted at the Oceanic Institute, where a similar set of diets were made with the covalently-bound and crystalline L-methionine and being tested at the Oceanic Institute’s indoor clean flow through system. Our collaborative efforts with researchers at TAMU also included defining the amino acid lysine requirements of the marine fish Moi, Pacific threadfin (Polydactylus sexfilis). A collaborator at TAMU sent us a mash of an amino acid (AA) test diet comprising a combination of red drum muscle and free amino acids (FAA). Results, TAMU red drum muscle and FAA diet is not suitable for this work because of the poor growth and survival. However a similar diet made at OI of Pacific threadfin (moi) muscle with AA diet provided better survival, and growth than the TAMU red drum muscle AA diet. This finding will be used to formulate a series of diets based on the use of moi muscle and FAA with graded levels of lysine. This project is monitored through meetings, conference calls, email communication, and on-site visits.