Nutritional characteristics of the potential aquaculture feed species Boekelovia hooglandii

Abstract

There are a variety of factors to be considered when choosing a particular species of microalgae for aquaculture feed, including growth rate, cell size, nutritional composition, digestibility and pigmentation. A good example of a microalga that fits these criteria is the chrysophyte Boekelovia hooglandii. This study investigates the growth rate and nutritional profile [protein, lipid (34 fatty acids), carbohydrate, and pigment (7 pigments)] of B. hooglandii to assess suitability as a feed. This study also identifies the peak concentrations and correlations among nutritional constituents. Under the tested conditions B. hooglandii exhibited a relatively high biomass productivity of 0.52gL−1day−1 dry weight (dw), in comparison with reported growth rates for three commonly used aquaculture feed algae, Isochrysis galbana (0.16gL−1day−1 dw), Tetraselmis suecica (0.27gL−1day−1 dw), and Pavlova sp. (0.28gL−1day−1 dw). In addition, the proportion of lipid, protein, and carbohydrate in the algal biomass on days 35 and 63 is suitable for bivalve larvae and juvenile oysters, respectively. A notable correlation identified in this study was between percent protein and growth rate (r=0.934, p=0.020), which highlights the nutritional changes occurring during culturing. As a consequence of the relatively high biomass and nutritional profile, B. hooglandii appears to be a suitable candidate as aquaculture feed for bivalve larvae and juvenile oysters. Statement of relevanceIdentified an algal species with high growth & ideal nutrients for oyster feed that is significantly greater in growth when compared to other commonly used species.