Submitted to: Book of Abstracts Aquaculture America
Publication Type: Abstract Only
Publication Acceptance Date: November 25, 2009
Publication Date: March 1, 2010
Citation: Rawles, S.D., Lochmann, R., Sink, T., Barrows, F., Bechtel, P.J. 2010. Partial replacement of menhaden oil with Alaskan pollack viceral meal in striped bass Morone saxatilis and sunshine bass M. chrysops X M. saxatilis diets [abstract]. Book of Abstracts Aquaculture America 2010. p.815. Technical Abstract: The recovery of waste by-products from the Alaskan fishery and use in fish feeds can potentially reduce pressure on fish harvested for animal feed applications. However, little data exist evaluating these by-products in moronid diets. Striped bass and sunshine bass growth, body composition, and immunological parameters were assessed after feeding diets containing 15% lipid from menhaden fish oil (MFO), a 3:1 mix of lipid from MFO and Alaskan Pollack visceral meal (APVM25) or a 1:1 mixture of lipid from MFO and APVM (APVM50). Sunshine bass (55 + or - 0.8 g) and striped bass (87 + or - 2.4 g) were randomly stocked in round 600-L fiberglass tanks supplied with constant aeration and flow-through well water in a 2 (taxa) x 3 (lipids) factorial design with N = 3 replicates per treatment. Fish were fed twice daily to apparent satiation for 11 wks and daily intake was recorded. Fish were weighed biweekly to compare growth trajectories of fish of different initial size using the relationship loge Gw = a – b loge Wm, where Gw is specific growth rate (SGR) and Wm is the mean within-tank fish weight during the trial. Most responses, including composition indices, were indifferent to changes in dietary lipid but differed by taxa. Final weights (Wf) of striped bass were greater than those of the hybrids, while gain as a percent of initial weight and SGR were greater in the hybrid, due to the smaller size of hybrids at stocking. However, overall growth trajectories were not different among taxa. Interaction of taxa and lipid were evident in average daily feed intake (ADI), feed efficiency (FE), lysozyme and alternative complement activities (ACH50). Fish consumed slighter more MFO diet than diets containing APVM in both taxa; however, this was offset by decreased FE of the MFO diet. The data suggest that APVM is a good choice for partial replacement of MFO in moronid diets.