2007 Annual Report
New funds will be used to expand Objective One of the research project plan:
1) Develop a series of trout feeds that replace fishmeal and fish oil with traditional and enhanced plant-derived ingredients. The focus should be on ingredient enhancement through biological and mechanical concentration of required nutrients for complete feed development. Expedite expanded capacity to increase select cultivars in trout feeding trials. This includes expanding strains being developed at Leetown, WV.
Dr. Keshun Liu: Objectives include;.
FY99 Program Increase $225,000 Add 1 SY for research on cereal grains & fish FY03 Program Increase $223,537 Add 1 SY FY04 Program Increase $241,566 Add 1 SY FY04 Program Increase $584,232 Add 1 SY FY05 Program Increase $111,600 Replaces 5366-21310-002-00D (12/04). FY06 Program Increase $89,100
The expression of genes and protein enzymatic activity of the three main degradation pathways in fish muscle was assessed and correlated with varying planes of nutrition. Understanding the genetic components of muscle accretion is important in determining the specific energy potential of alternative feed material in diets and selected rainbow trout. At the Hagerman Fish Culture Experiment Station in Hagerman, Idaho tissue samples were obtained from rainbow trout that were fully fed, starved for several weeks, or starved and then refed for several days and analyzed for the expression of degradation genes and for enzymatic activity. The development of markers for improved degradation profiles in fish has the potential to select for fish with significantly improved growth rates. These studies address the NP106 components of genetic improvement, Problem C. Genomic Resources and were conducted at the Hagerman Fish culture Experiment Station in collaboration with the University of Idaho.
Genetic mapping of low-phytate mutations in barley.
Phytate is the major storage form of phosphorus in grains but it is not digestible for monogastric animals including poultry, pigs, and fish which can result in a source of water polution. Phytate also binds other minerals such as iron and reduces the availability of minerals to animals. A better understanding the genetic mechanism of phytate biosynthesis will eventually improve the nutritional value of grains and reduce the impact of animal agriculture on the environment. To understand the phytate metabolic pathway, we mapped 17 additional low phytate mutations in barley. Our results indicate that at least 6 genetic loci are involved in the barley low phytate mutant collection. This research not only provides insight into the genetic study of phytate in plants, but also makes barley a better model system. These studies address the NP106 components of Growth, Development and Nutrition, Problem C, Sustainable Source of Nutrients.
Dry fractionation methods to enrich cereal grain protein
Several methods of dry fractionation were compared to determine which method or combinations of methods were best for separating barley into high protein fractions with an acceptable production yield. We found that milling followed by sieving separated fractions with varying protein contents. Yet, the method of milling significantly affected the efficiency of protein enrichment and the protein content in individual sized fractions. The abrasive milling produced sieve sized fractions with much higher variation in protein content than the impact milling. Yet, when the two methods of milling followed by sieving were compared with a single process of pearling (debranning), the later was found to be the best approach to produce barley fractions with highest protein content. Since fractions with high protein concentration tended to be low in mass, there is a need to make a balance between protein enrichment levels and mass recovery of resulting fractions. Based on data of pearled bran fractions and sieve sized fractions, it was possible to produce a combined fraction having a 50% increase in protein content with over 50% of total seed mass. These studies address the NP106 components of Growth, Development and Nutrition, Problem C, Sustainable Source of Nutrients.
Inability of methionine to preclude taurine supplementation in plant protein diets for rainbow trout.
Taurine has previously been identified as a potential limiting nutrient in plant-based diets for rainbow trout, although rainbow trout have some capacity for taurine biosynthesis from sulfur amino acid precursors. Methionine is the precursor sulfur amino acid that can economically be supplemented to animal feeds potentially more cost effectively than taurine. The experiment tested the efficacy of supplementing methionine and taurine separately and in combination on production performance of rainbow trout. Using metabolite profiling technologies this experiment determined that supplementing taurine was more efficacious in supplying taurine that the bioconversion of methionine to taurine. The impact of this research will be to further verify the need for taurine supplementation in plant-based diets for rainbow trout and continue to refine plant-based aquafeeds and reduce dependence on fish meals. These studies address the NP106 components of Growth, Development and Nutrition, Problem D. Nutrient Use and Feed Evaluation, and were conducted at the Hagerman Fish culture Experiment Station in collaboration with the University of Idaho.
Evaluation of NRC vitamin requirements in extruded trout diets based upon either fish meal or plant meal.
The recommended vitamin levels in trout diets by the NRC do not account for the effect of cooking extrusion or the primary protein source, fish meal versus plant meals. A 16 week feeding study identified vitamin E deficiency in fish meal based diets, and pantothenic acid in plant meal based diets, to be the first deficiency symptoms observed. Vitamin premixes should be adjusted for extrusion and a recommended premix was developed. This open-formula vitamin premix is being adopted in the place of outdated formulation produced by other government agencies, and its use will reduce feed costs and more adequately supply essential vitamins to rapidly growing fish. These studies address the NP106 components of Growth, Development and Nutrition, Problem D. Nutrient Use and Feed Evaluation, and were conducted at the Hagerman Fish culture Experiment Station in collaboration with the University of Idaho.
Liu, K., Peterson, K.L., Raboy, V. 2007. Comparison of the Phosphorus and Mineral Concentrations in Bran and Abraded Kernel Fractions of a Normal Barley (Hordeum vulgare) Cultivar versus Four Low Phytic Acid (lpa) Isolines. Journal of Agricultural and Food Chemistry. 55:4453-4460.
Gaylord, T.G., Teague, A.M., Barrows, F.T. 2006. Taurine supplementation of all-plant protein diets for rainbow trout oncorhynchus mykiss.. Journal of the World Aquaculture Society. 37:509-517.
Gaylord, T.G., Barrows, F., Teague, A.M., Johansen, K.A., Overturf, K.E., Shepherd, B.S. 2007. Supplementation of taurine and methionine to all-plant protein diets for rainbow trout (Omcorhynchus mykiss). Aquaculture 269:514-525.
Gatlin Iii, D., Barrows, F., Bellis, D., Brown, P., Campen, J., Dabrowski, K., Gaylord, T.G., Hardy, R.W., Herman, E.M., Hu, G., Krogdahl, A., Nelson, R., Overturf, K.E., Rust, M., Sealey, W., Skonberg, D., Souza, E.J., Stone, D., Wilson, R.F. 2007. Expanding the Utilization of Sustainable Plant Products in Aquafeeds – A Review. Aquaculture Research. 38:551-579.
Barrows, F., Stone, D.A., Hardy, R.W. 2007. The effects of extrusion conditions on the nutritional value of soybean meal for rainbow trout (Oncorhynchus mykiss. Aquaculture, Elsevier Science. v 265:244-252
Liu, K., Fu-Hung, H. 2007. Protein-Protein Interactions in high moisture-extruded meat analogs and heat-induce soy Protein Gels. Journal of the American Oil Chemists' Society. 84(8):741-748
Liu, K. 2007. Laboratory Methods to Remove Surface Layers from Cereal Grains Using a Seed Scarifier and comparison with a barley pearler.. Cereal Chemistry.84(4):407-414
Liu, K. A modified Laboratory Method to Remove Outer Layers from Cereal Grains Using a Barley Pearlier. 2007 Cereal Chemistry. 84(4):407-414.