Enriching Rotifers with “Premium” Microalgae. Nannochloropsis gaditana

Abstract

The nutritive quality of Nannochloropsis gaditana cultured semicontinuously with different daily renewal rates was tested as a diet for short-term enrichment of the rotifer Brachionus plicatilis. After 24 h, dramatic differences in the survival, dry weight, and biochemical composition of the rotifers depending on the renewal rate of microalgal cultures were observed. Survival after the feeding period increased with increasing renewal rates. Rotifers fed microalgae from low renewal rate, nutrient-deficient cultures showed low dry weight and organic contents very similar to those of the initial rotifers that were starved for 12 h before the start of the feeding period. On the contrary, rotifers fed nutrient-sufficient microalgal cells underwent up to twofold increases of dry weight and protein, lipid, and carbohydrate contents with regard to rotifers fed nutrient-depleted N. gaditana. Consequently, feed conversion rate decreased in these conditions, indicating a better assimilation of the microalgal biomass obtained at high renewal rates. No single microalgal biochemical parameter among those studied can explain the response of the filter feeder. Similarly to gross composition, EPA and n-3 contents in rotifers fed microalgae from nutrient-sufficient cultures were double than the contents found in rotifers fed nutrient-limited microalgae. In addition, very high positive correlations between the contents of EPA and n-3 in N. gaditana and B. plicatilis were observed. These results demonstrate that selecting the appropriate conditions of semicontinuous culture can strongly enhance the nutritional value of microalgae that is reflected in the growth and biochemical composition of the filter-feeder even in short exposure periods.

Ultrastructure and Composition of the Nannochloropsis gaditana Cell Wall

“…Several Nannochloropsis species have been studied as candidate production strains in large-scale biofuel facilities because of their hardy outdoor growth profiles and high lipid yields (4)(5)(6)(7)(8)(9). They are also producers of valuable pigments (10) and nutritive oils (11,12) and are commonly used as an aquaculture feed (13).…”

Selection of Suitable Species of Chlorella, Nannochloris, and Nannochloropsis in High- and Low-Temperature Seasons for Mass Culture of the Rotifer Brachionus plicatilis

“…Examples of commonly used microalgae and yeast include the microalgae Nannochloropsis (Fukusho, 1989;Kostopoulou and Vadstein, 2007;Ferreira et al, 2009), Chlorella (Maruyama et al, 1997;Cabrera et al, 2005;Zhou et al, 2009), and Nannochloris (Witt et al, 1981;Hur, 2001, Cho et al, 2007), and the yeasts bread yeast Saccharomyces cerevisiae (Gilberto and Mazzola, 1981;Sarma et al, 2002;Wang et al, 2009) and marine yeast Candida utilis (Kim et al, 2005).…”

Effect of Un-live Microalgal diet, Nannochloropsis oculata and Arthrospira (Spirulina) platensis, Comparing to Yeast on Population of Rotifer, Brachionus plicatilis

“…Striped mullet and milkfish fed rotifers grown on yeast have lower survival than fish fed rotifers that are grown on microalgae or a combination of microalgae and yeast. Ferreira et al, (2009) reported that Nannochloropsis sp. is widely used for rotifer production since it supports higher growth rates than baker's yeast and provides the rotifers with high amounts of EPA.…”

“…HUPArich microalgae such as Isochrysis and Pavlova contain high DHA levels and can be fed to B. plicatilis for DHA enrichment, which results in DHA/EPA ratios above 2.0 (Hemaiswarya et al, 2011). However, the nutritional value of baker's yeast (as not laborious, not time consuming and not expensive diet for rotifer) may be enhance easily by adding of marine oil enrichment, especially EPA and DHA that are needed for all marine larvae (Ferreira, et al, 2009).…”

“…Therefore, the production demand of rotifers is extremely high in order to support marine fish culture (Lind., 2014) Since Hirata and Mori (1967) introduced the use of bakers' yeast Saccharomyces cerevisiae as food for marine rotifer B. plicatilis, number of investigators, researchers and aquaculture have been used bakers' yeast as food for this species; rotifers grown in this way have also been nutritionally enriched. Moreover, oil enrichment, artificial diets, baker yeast and baker's yeast with added marine oils may be used as rotifer diets as worldwide cheap food for the production of B. plicatilis (Ferreira, et al, 2009). There are advantages and disadvantages in using each of algae and yeast in culturing rotifer (Lind., 2014).…”