2006 Annual Report
The research to be undertaken is aligned with National Program 106-Aquaculture and addresses the goals of genetic improvement, reproduction and early development, and growth, development and nutrition. Specifically, we address: Genetic improvement: traditional animal breeding, broodstock development, germplasm preservation, molecular genetics to address improvement of growth rates, feed efficiency, survival, disease resistance, and product quality; conservation and utilization of important aquatic germplasm for use by producers. Reproduction and early development: improvement of systems to enhance reproductive efficiency. Growth, development and nutrition: elucidate factors affecting growth rates, feed conversion and feed formulations and feeding strategies to reduce dependence on marine fish-based protein in aquaculture diets.
Aquaculture producers and the public will benefit from improved productivity of superior strains rainbow trout being developed, and the reduced environmental impact of fish with greater efficiency. Additionally, this research supports the integration of selective breeding with identification of the genes contributing to variation in the traits. Improved integration of traditional breeding practices with molecular genetic information will speed improvement resulting in a supply of healthy foods that are produced more efficiently.
Objective 2: a. Evaluate in vivo effects of growth hormone (GH) secretogogues on GH release in rainbow trout b. Assess the use of GH secretogogues to alter feeding in rainbow trout and develop methods to measure feed efficiency and genetic variation in feed efficiency c. Determine association between stress responsiveness (plasma cortisol following a crowding stress), and disease resistance to Yersinia ruckeri
Objective 3: a. Define pressure treatment protocols for induction of tetraploidy (4N) in four lines of rainbow trout and produce several 4N families of rainbow trout by crossing 1st generation 4N parents b. Produce several 3N families by crossing 4N X 2N parents and compare to normal diploids for viability and growth
Year 2 (FY2006): Objective 1. a. Production of broodyear 2006, estimate genetic and phenotypic correlations between growth and Flavobacterium resistance b. Estimate the proportion of total variation due to genotype x environmental effects and screen families for genotype x diet interaction c. Test transgenic fish for disease resistance, identify muscle specific promoter d. Cryopreserve milt from NCCCWA and transgenic fish
Objective 2. a. Evaluate in vivo effects of growth hormone (GH) secretogogues on GH release in rainbow trout b. Contrast endocrine response to fasting and re-feeding to identify hormones and genes that regulate feeding and growth, and determine the relationship between feed efficiency of individuals and their full-sib families c. Determine association between stress response (plasma cortisol following a crowding stress) and response to ACTH d. Identify ovarian genes altered in response to follicle recruitment after unilateral ovariectomy, and Identify changes in expression of growth factors during ovarian development
Objective 3. a. Produce four 4N families from five selected NCCCWA families and make ten 2nd generation 4N families of even-year lines with defined genetic backgrounds b. Evaluate production traits of (1) 3Ns from crosses, (2) 3Ns from pressure treatment and (3) 2Ns, all from even-year lines and of similar genetic background and compare stress response of 2N and 3N animals
Year 3 (FY2007): Objective 1. a. Produce BY 2007 germplasm through selective breeding and estimate genetic parameters for quality traits, and evaluate realized heritability for growth b. Estimate the proportion of total variation due to GxE effects for reproductive traits and estimate the proportion of total variation due to genotype x diet effects on growth c. Test transgenic fish for disease resistance, breed transgenic lines to homozygosity d. Produce >10 all female families with sex reversed males
Objective 2. a. Determine effects of sex steroids on pituitary responsiveness to GH secretogogues b. Determine effect of GH secretogogue-supplemented feed on growth, feed intake and efficiency and longitudinal evaluation of feed efficiency over time c. Determine heritability of stress responsiveness (plasma cortisol following a crowding stress)
a. Make ten 2nd generation 4N families of odd-year lines with defined genetic
b. Evaluate production traits of.
Year 4 (FY 2008): Objective 1. a. Produce BY 2008 germplasm through selective breeding and estimate correlations with quality traits and evaluate realized heritability for Flavobacterium resistance b. Estimate the proportion of total variation due to genotype x diet effects on reproduction c. Test anti-microbial peptide (AMP) transgenic fish for disease resistance and amplify disease resistant transgenic lines to introgress 10 crosses into a Leetown line d. Produce >30 all female families with sex reversed males
Objective 2. a. Evaluate variation in endocrine measures of growth and associations with growth performance in brood year 2006 fish b. Determine if fish selected for an improved stress response to crowding, also exhibit an improved stress response to a temperature or salinity stress c. Evaluate growth factors, identified from studies in 2006, for their ability to affect ovarian development
Objective 3. a. Make ten 3rd generation 4N families of even-year lines with defined genetic backgrounds b. Determine the combination of 4N and 2N parental lines that yield superior 3N offspring for commercial production c. Analyze advanced generations of 4N fish for changes in gene content/frequency and chromosomal make-up
Year 5 (FY 2009): Objective 1. a. Produce BY 2009 germplasm through selective breeding and estimate correlations with quality traits and evaluate realized heritability for Flavobacterium resistance b. Estimate the proportion of total variation due to genotype x diet effects on reproduction c. Test AMP transgenic fish for disease resistance and amplify disease resistant transgenic lines to introgress 10 crosses into a Leetown line d. Produce >70 all female families with sex reversed males
Objective 2. a. Evaluate variation in endocrine measures of growth and associations with growth performance in brood year 2008 fish b. Identify QTL for stress responsiveness c. Identify genes and hormones in eggs that affect egg quality
Objective 3. a. Make ten 3rd generation 4N families of odd-year lines with defined genetic backgrounds b. Identify 4N rainbow trout lines to be released and tested under commercial conditions c. Define the genetic stability/volatility of different 4N lines of fish and evaluate commercial applicability
Genotype x diet interactions in rainbow trout families NP106 Genetic improvement action plan item b. Selective breeding for commercially important traits. Over two years more than 30 families of NCCCWA rainbow trout were raised at the University of Idaho, Hagerman Fish Culture Experiment Station on two diets, one high in soybean meal and the other without soybean meal, to test the genotype x diet interaction. There were significant genetic and diet effects on feed intake, growth rate and feed efficiency, but the genotype x diet interaction effect was not important. This suggests that the fish selected for growth on today’s typical diets will be the best performers on diets of tomorrow if they incorporate higher levels of plant protein sources. This will encourage improvement of today’s lines of fish for better performance in the future
Additionally, this report documents research conducted under a specific cooperative agreement between ARS and University of Idaho (1930-31000-007-04S, Evaluation of Selected Rainbow Trout Lines Fed Grain Based Diets Under Farm Scale Conditions). Fish from 33 genetic groups were evaluated at the University of Idaho, Hagerman facility. Each genetic group was divided into 4 replicate tanks and fed either a control diet high in fishmeal content or a diet high in protein from soybeal meal. Family and diet effects were large, however the effects of family x diet were mostly small. The most important family x diet interaction effect was for feed efficiency.
A reimbursable agreement was established for ARS scientist Brian Shepherd’s funding through the CSREES NRI program grant (1930-31000-007-02R Innovative approaches to growth enhancement in teleosts). Work under this agreement has was begun, and tools for quantifying growth axis hormones and neuropeptides were developed and validated. When Brian Shepherd moved to Wisconsin, the agreement was terminated (on Dec. 31, 2005) and moved with him.
2) Silverstein J.T. 2006. One fish, two fish, red fish and three blue fish. The Fish Line-Colorado Aquaculture Newsletter 18(2):5-6. log# 194251
3) Silverstein J.T., Palti Y, Vallejo R, Welch T, and Wiens G, 2006. Cracking the code: Selecting for resistance against bacterial cold-water disease. US Trout Farmers' Association Newsletter, Trout Talk: Fall 2006 log# 198916
Silverstein, J. Cryopreservation activities and needs at the National Center for Cool and Cold Water Aquaculture. Aquaculture America Conference. Aquaculture America Book of Abstracts 2006, pg 287.
Silverstein, J., Hardy, R., Casten, M., Barrows, F. 2006. Genotype diet interactions in rainbow trout families fed diets with and without high levels of soybean meal inclusion. International Symposium on Genetics in Aquaculture. p. 97.
Silverstein, J. 2006. Producing all female rainbow trout: do neomales affect the growth of their sibilings?. Aquaculture America Conference February 13, 2006, Las Vegas, NV.
Silverstein, J. 2006. Relationships among feed intake, feed efficiency and growth in juvenile rainbow trout (Oncorhynchus mykiss). North American Journal of Aquaculture.68:168-175.
Silverstein, J., Brazil, B.L., Salem, M.S., Cox, M.K., Blemings, K.P., Yao, J. 2006. Ammonia excretion as an indicator of growth efficiency. Aquaculture America Conference. Aquaculture America Book of Abstracts. Pg. 285.
Silverstein, J., Weber, G.M., Rexroad Iii, C.E., Vallejo, R.L. 2006. Genetics and genomics-intregration of breeding and molecular genetics programs. Meeting Abstract. Presented at BARD sponsored workshop on Aquaculture Genetics in Eilat, Israel, Feb 20-23, 2006.
Gahr, S.A., Weber, G.M., Rexroad III, C.E. 2006. Fasting and refeeding effects the expression of the inhibitor of dna binding (id)genes in rainbow trout (Oncorhynchus mykiss) muscle. Comparative Biochemistry and Physiology. 144:472-477.
Higgins, A., Silverstein, J., Engles, J., Wilson, M., Rexroad III, C.E., Blemmings, K. 2006. Starvation induced alterations in hepatic lysine metabolism in different families of rainbow trout (Oncorhynchus mykiss). Fish Physiology and Biochemistry Journal. 31(1):33-44.
Lankford, S.E., Weber, G.M. 2006. Associations between plasma growth hormone, insulin-like growth factor-1 and cortisol, with stress responsiveness and growth performance in a selective breeding program for rainbow trout (oncorhychus mykiss). North American Journal of Aquaculture 68, 151-159.
Palti, Y., Silverstein, J., Wieman, H., Phillips, J.G., Barrows, F.T., Parsons, J. 2005. Evaluation of family growth response to fish meal and gluten-based diets in rainbow trout (oncorhynchus mykiss). Aquaculture. 255 (1-4):548-556.
Lankford, S.E., Weber, G.M. 2006. Potential roles of intraovarian growth factors during follicle maturation in rainbow trout (Oncorhynchus mykiss). Meeting Abstract.