New VitaBloom^® product range: microalgae combined with probiotics for green water, rotifer nutrition, and live feed enrichment

The development of microalgae products to solve larviculture challenges is essential to advance the fast-growing aquaculture sector. Combining different microalgae and probiotics is a powerful tool to improve animal nutrition and enhance biological performance, resilience to pathogens, and fish stress coping abilities. Products were used with a green water technique, rotifer cultivation, and live feed enrichment (rotifers and artemia). VitaBloom^® Green Water (VGW) was applied to Argyrosomus regius larviculture until weaning, and compared to live Nannochloropsis sp. (n=3). Larvae at 19 days post fertilization (dpf) showed a significant reduction in skeletal malformations affecting phenotypes (24%) compared to the control (50%), displaying similar survival (20dpf). Vibrionaceae (TCBS) in water also decreased (1.23Log₁₀CFU/ml vs. 1.93Log₁₀CFU/ml). The stress-inducing challenge of transportation was carried out post-weaning. Larvae cultured with VGW revealed higher survival (93.0±1.3%) compared with controls (68.2±18.3%). Rotifers were batch cultured with VitaBloom^® Rotifers+ (VR) or a commercial product (CP). VR showed a significantly reduced decantation (0.16±0.03cm) and agglomeration (0.05±0.04%) compared to controls (0.28±0.07cm and 0.5±0.4%, respectively), significantly improving rotifer growth rate (266±16.7%) and amictic females (28.8±7.5%) compared to the CP (160±13.2% and 23.3±9.8%, respectively). Rotifers and artemia were enriched with VitaBloom^® Enrich (VE) or a CP for Sparus aurata larviculture until weaning (n=4). Although there were no significant differences, larvae fed with live feed enriched with VE revealed 18.7±7.3% of larvae survival at weaning, while larvae fed with live feed enriched with the CP resulted in 15.5±7.7% survival at weaning. The synergetic effect of the three VitaBloom^® products was tested in S. aurata larviculture until weaning compared to larvae cultured with three CPs (n=3). Larvae fed with VitaBloom^® showed higher survival at weaning (11.0±2.3%) compared to controls (6.6±5.0%). These innovative, sustainable, and efficient products are essential in improving larvae survival, which constrains the productivity and growth of the vital aquaculture industry.