A defatted microalgae meal (Haematococcus pluvialis) as a partial protein source to replace fishmeal for feeding juvenile yellow perch Perca flavescens

Authors: JIANG, M. - University Of Wisconsin; ZHAO, H. - University Of Wisconsin; ZHAI, S. - University Of Wisconsin; Shepherd, Brian; WEN, H. - University Of Wisconsin; DENG, D. - University Of Wisconsin

Submitted to: Journal of Applied Phycology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/12/2018
Publication Date: 8/30/2018
Publication URL: http://handle.nal.usda.gov/10113/6364951
Citation: Jiang, M., Zhao, H., Zhai, S., Shepherd, B.S., Wen, H., Deng, D.F. 2019. A defatted microalgae meal (Haematococcus pluvialis) as a partial protein source to replace fishmeal for feeding juvenile yellow perch Perca flavescens. Journal of Applied Phycology. 31:1197–1205. https://doi.org/10.1007/s10811-018-1610-3.
DOI: https://doi.org/10.1007/s10811-018-1610-3

Interpretive Summary: Alternative protein and lipid sources are urgently required to make aquafeeds sustainable and affordable as a means to reduce reliance on traditional fish-meals and fish oils for the aquaculture industry. As opposed to terrestrial plant protein sources, seaweeds possess dispensable and indispensable amino acids, as well as micronutrients such as vitamins and minerals, which are required for proper animal development and growth. In addition to being a possible protein source, cell wall components of seaweeds also possess pre-biotic components that may also benefit production performance in finfish and shellfish fed such protein sources. The initial objective of this study was to investigate the potential of a co-product, defatted microalgae meal (DMM), as a feed ingredient for yellow perch (Perca flavescens). Substitution of fishmeal was accomplished using a 1:1 mixture of DMM and soy protein isolate (SPI) to replace 25, 50 or 75% of fishmeal in a yellow perch diet. Replacement of 25% fishmeal with the combined mixture had no adverse effect on the growth performance, nutrient composition or serum biochemical indexes compared with fish fed a standard control diet. Also, fish fed the algae meal supplemented diets showed improved pigmentation in their pelvic fins. Results of this study indicates that DMM, when blended with SPI, can be used to replace 25% of the fishmeal in a standard test diet while maintaining performance of yellow perch. Additional studies will evaluate whether use of DMM can improve immune functions in yellow perch and rainbow trout.

Technical Abstract: The objective of this study was to investigate the potential of a co-product, defatted microalgae meal (Haematococcus pluvialis), as a feed ingredient for yellow perch (Perca flavescens). A mixture of the ingredient combining the algae meal and soy protein isolate (at a ratio of 1:1) was added to the control diet at levels of 10, 20, or 30%to replace 25, 50, or 75%of fishmeal in a control diet. Yellow perch (initial body weight, 13.1 ± 1.6 g; 30 fish/tank; n = 3 tanks) were fed the test diets for 8 weeks in an indoor system with flow-through water at 22 °C. The results showed that replacement of 25% fishmeal with the combined mixture had no adverse effect on the growth performance, proximate composition, and serum biochemical indexes compared with the control diet (P > 0.05). However, fish fed the diets with 50 or 75% fish meal replacement were shown to have significantly reduced growth compared to fish fed the control diet or the diet with 25% fish meal replaced (P < 0.05). Increased use of the combined ingredient to replace 50% fishmeal in the current formulations may have led to nutrient imbalance such as amino acids, or minerals in the test diets. Supplementation of limited nutrients into the defatted algae meal may potentially increase the potential of the byproduct used as a feed ingredient. This needs to be investigated in future study. Results of this study indicate that the defatted microalgae meal blended with soy protein isolate can be used to (10% of the diet) replace 25%of the fish meal in the test diet without compromising the performance of yellow perch under current testing conditions.