Submitted to: International Symposium on Genetics in Aquaculture
Publication Type: Abstract Only
Publication Acceptance Date: 5/15/2006
Publication Date: 6/26/2006
Citation: 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.
Technical Abstract: The USDA/ARS National Center for Cool and Cold Water Aquaculture (NCCCWA) is developing improved germplasm for rainbow trout through a family based selective breeding program for faster growth and enhanced resistance to bacterial coldwater disease. Increasing concerns over potential negative environmental impacts, and increasing demand for marine proteins as feed ingredients have prompted examination of alternate diet formulations for aquaculture. There is a question whether fish that perform best on traditional fishmeal-based diets will perform best using these alternate diets. To investigate genotype x diet interactions two practical diets, one with and one without soybean meal, were fed to 33 families of rapidly growing juvenile rainbow trout for two months. Each of 33 families was reared in quadruplicate tanks, two replicates were fed each diet. Growth, growth rate and feed conversion ratio (FCR) were determined for each replicate. The main sources of variation were family (genotype), diet and genotype x diet. Preliminary analysis showed that growth, growth rate and FCR were significantly better on the diet without soybean meal and that genotype had highly significant effects. The genotype x diet interaction was statistically significant only for FCR. This work contributes a study using practical diets to the accumulating evidence suggesting that growth performance is not strongly affected by genotype x diet interaction on alternate diets.