The development of new microalgae products to solve current marine fish larvae production challenges in aquaculture is essential to enhance this fast-growing food production sector. The combination of different microalgae and probiotics is a powerful tool to improve animals’ nutrition and can be used as a prophylaxis to enhance biological performance, resilience to pathogens and fish stress coping abilities. Microalgae are used in green water technique, rotifer cultivation and live feed enrichment (rotifers and artemia). VitaBloom® Green Water was applied to meagre (Argyrosomus regius) larviculture until weaning in comparison to live Nannochloropsis sp. (n=3 tanks). Larvae at 19 days post fertilization (dpf) showed a significant reduction of skeletal malformations affecting phenotype (24%) compared to the control (50%), displaying similar survival (20dpf) and reduction of Vibrionaceae bacteria (TCBS) in the water (1.93Log10CFU/ml, 1.23Log10CFU/ml respectively). A stress challenge of transport was performed post-weaning, where larvae cultured with VitaBloom® Green Water revealed higher survival (93.0±1.3%) compared with control (68.2±18.3%). VitaBloom® Rotifers+ was used in rotifers cultivation in batch (3 days) compared to a commercial product. VitaBloom® Rotifers+ showed a significant reduction of product decantation (0.160±0.03cm), microalgae agglomerates abundance (0.05±0.04%) and dimensions (16.8±7.7µm) compared to control (0.280±0.07cm, 0.5±0.4% and 21.0±8.3µm respectively). VitaBloom® Rotifers+ significantly improved rotifers growth rate (266±16.7%) and amictic females (28.8±7.5%) compared to rotifers produced with a commercial product (160±13.2% and 23.3±9.8% respectively). VitaBloom® Enrich was used in gilthead seabream (Sparus aurata) larviculture until weaning, with an initial density of 76larvae/L, in comparison with a commercial enrichment product (n=4 tanks). In this experiment, green water was performed with live Nannochloropsis sp. and rotifers cultured with a standard product (PhytoBloom®Green Formula) in both treatments. Although there were no significant differences, larvae fed with enriched live feed with VitaBloom® Enrich revealed 18.7±7.3% of larvae survival at weaning and larvae fed with live feed enriched with a commercial product resulted in a 15.5±7.7% survival at weaning. The synergetic effect of the 3 VitaBloom® products was tested in S. aurata larviculture until weaning compared to larvae cultured with 3 commercial products (n=3 tanks). Larvae fed with VitaBloom® showed higher survival at weaning (11.0±2.3%) compared to control (6.6±5.0%). The development of VitaBloom® innovative, sustainable and effective microalgae solutions in powder is highly advantageous for the aquaculture industry due to the logistics simplification, displaying a balanced nutrition for fish and supporting their health. It is noteworthy, that the synergistic effect of VitaBloom® range can enhance by up to 13.4% (6064€) the nursery S. aurata sales per million larvae, boosting production in this relevant food sector.
Acknowledgements
Supported by Project Allarvae - 069971 supported by CRESC Algarve, Portugal 2020 and European Union.