|BERG, LEVI - West Virginia University|
|GATRELL, STEPHANIE - West Virginia University|
|GRIMMETT, JUANITA - West Virginia University|
|Leeds, Timothy - Tim|
|Weber, Gregory - Greg|
|KLANDORF, HILLAR - West Virginia University|
|TURK, PHILIP - West Virginia University|
|SEMMENS, KENNETH - West Virginia University|
|BLEMINGS, KENNETH - West Virginia University|
Submitted to: Federation of American Societies for Experimental Biology Conference
Publication Type: Abstract Only
Publication Acceptance Date: 1/15/2012
Publication Date: 4/4/2012
Citation: Berg, L., Gatrell, S., Cleveland, B.M., Grimmett, J., Leeds, T.D., Weber, G.M., Klandorf, H., Turk, P., Semmens, K., Blemings, K. 2012. Effect of genetics and feeding strategies on growth of rainbow trout. Federation of American Societies for Experimental Biology Conference. 125.
Technical Abstract: The effects of both selective breeding for increased growth and feeding strategy on growth performance and indices of protein degradation were determined in rainbow trout. For 24 weeks, control and growth-selected fish were fed either to satiation or limit-fed at 90-95% of the feeding rate required to reach maximal growth. The length and weight of 1600 fish were measured every 6 weeks. At the end of the study there was an interaction (p<0.05) between feeding strategy and selective breeding for both length and weight. The least squares means ± standard error of the means for weight of satiation/control, limit-fed/control, satiation/selected and limit-fed/selected fish were 371 +\- 6, 350 +\- 4, 544 +\- 24, and 426 +\- 16 grams and for length 299 +\- 2, 291 +\- 2, 347 +\- 2 and 330 +\- 2 mm, respectively. mRNA expression of four components of the ubiquitin/proteasome machinery was decreased (p<0.05) by an average of 17% in white muscle in growth-selected fish. Caspase 3 and caspase 9 expression was also decreased in growth-selected fish (P<0.05) by an average of 18%. No effect of feeding strategy was observed for proteolytic gene expression and no differences in plasma insulin-like growth factor-I were detected due to feeding strategy or selective breeding. These data suggest that a reduced capacity for muscle protein degradation is a mechanism that contributes to increased weight gain in rainbow trout selectively bred for faster growth.