Location: Cool and Cold Water Aquaculture Research2015 Annual Report
1. Improved growth performance in rainbow trout would enhance industrial trout production. ARS researchers at Leetown, West Virginia, selected a pedigreed rainbow trout line for improved growth performance over five generations and achieved an average improvement of approximately 13% per generation in body weight at both 9 and 13 months of age. The line was also characterized for genetic control of an array of production, fillet quality, and reproductive traits. Ultrasound was verified as a non-invasive approach to characterize carcass composition and quality traits. Favorable results from efforts with the largest domestic producer of rainbow trout to improve fillet yield in their population. Results have led to ongoing, large-scale field trials to provide further characterization of its performance in production settings in anticipation of its industry release and an ongoing collaboration with the largest domestic producer of rainbow trout to improve fillet yield in their population.
2. Phytoestrogens are plant-derived isoflavones that may affect growth performance of rainbow trout. Phytoestrogen content of aquafeeds is increasing due to higher inclusion levels of soy and other legumes rich in these compounds. It is unknown whether phytoestrogens affect growth-related processes in a manner similar to the catabolic effects of estradiol. ARS researchers in Leetown, West Virginia, conducted a series of in vitro and in vivo studies to determine effects of phytoestrogens on metabolic and physiological mechanisms in rainbow trout. Results indicated that genistein, the phytoestrogen of greatest abundance in soy, increases protein degradation and reduces protein synthesis and cell proliferation in cells from white muscle. Furthermore, when injected into fish, genistein affected expression of genes related to growth and protein and lipid metabolism in a manner similar to estradiol, supporting that these compounds negatively affect growth performance, however results suggested that at low levels of genistein may be beneficial for muscle growth. Collectively, these results suggest that dietary phytoestrogens affect rainbow trout growth performance, although whether the response is positive or negative may be concentration dependent.
Cleveland, B.M., Weber, G.M. 2014. Effects of sex steroids on expression of genes regulating growth-related mechanisms in rainbow trout (Oncorhynchus mykiss). General and Comparative Endocrinology. DOI:10.1016/j.ygcen.2014.11.018.
Sieliez, I., Dias, K., Cleveland, B.M. 2014. Contribution of the autophagy-lysosomal and ubiquitin-proteasomal proteolytic systems to total proteolysis in rainbow trout (Oncorhynchus mykiss) myotubes. American Journal of Physiology - Regulatory Integrative & Comparative Physiology. 307(11):R1330-R1337. DOI: 10.1152/ajpregu.00370.2014.
Manor, M.L., Weber, G.M., Cleveland, B.M., Yao, J., Kenney, P. 2015. Expression of genes associated with fatty acid metabolism during maturation in diploid and triploid female rainbow trout. Aquaculture. 435:178-186.
Cleveland, B.M., Manor, M.L. 2015. Effects of phytoestrogens on growth-related and lipogenic genes in rainbow trout (Oncorhynchus mykiss). Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology. 170:28-37. DOI: 10.1016/j.cbpc.2015.02.001.
Weber, G.M., Davidson, J.W., Kenney, P.B., Good, C.M., Manor, M.L., Welsh, C., Aussanasuwannakul, A., Summerfelt, S.T. 2015. Changes in sex steroids, growth hormone, and insulin-like growth factor-I during ovarian development in Rainbow Trout cultured within a recirculating system with 24-hour Light. North American Journal of Aquaculture. 77:186-194. DOI: 10.1080/15222055.2014.987933.
Manor, M.L., Cleveland, B.M., Weber, G.M., Kenney, P. 2014. Effects of feeding level and sexual maturation on fatty acid metabolism gene expression in muscle, liver, and visceral adipose tissue of diploid and triploid rainbow trout, Oncorhynchus mykiss. Comparative Biochemistry and Physiology. 179:17-26.
Ma, H., Weber, G.M., Hostuttler, M.A., Wei, H., Wang, L., Yao, J. 2015. MicroRNA expression profiles from eggs of different qualities associated with post-ovulatory ageing in rainbow trout (Oncorhynchus mykiss). Biomed Central (BMC) Genomics. 16(201).1-9. DOI: 10.1186/s12864-015-1400-0.
Weber, G.M., Hostuttler, M.A., Semmens, K.J., Beers, B.A. 2015. Induction and viability of tetraploids in brook trout (Salvelinus fontinalis). Canadian Journal of Fisheries and Aquatic Sciences. DOI: 10.1139/cjfas-2014-0536.
Good, C., Weber, G.M., May, T., Davidson, J., Summerfelt, S. 2015. Reduced photoperiod (18 h light vs 24 h light) during first-year rearing associated with increased early male maturation in Atlantic salmon Salmo salar cultured in a freshwater recirculation aquaculture system. Aquaculture Research. DOI: 10.1111/are.12741.
Liu, S., Vallejo, R.L., Gao, G., Palti, Y., Weber, G.M., Hernandez, A., Rexroad III, C.E. 2015. Identification of single nucleotide polymorphism markers associated with cortisol response to crowding in Rainbow Trout. Marine Biotechnology. DOI: 10.1007\s10126-015-9621-4.