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Algae as functional ingredients in Senegalese sole microdiets Maria Morais, Diogo Peixoto Daniel Afonso, Helena Abreu, Joana Silva, João Navalho, Wilson Pinto, Benjamin Costas, Ana Gonçalves, SPAROS, CIIMAR, Algaplus, Allmicroalgae - Natural Products S.A., Necton S.A., GreenCoLab
Figure 1. a) Nannochloropsis sp. cells. Photo: Allmicroalgae. b) Dried Gracilaria gracilis. Photo: AlgaPlus.
Algae as functional ingredients for fish larvae Micro- and macro-algae are rich sources of bioactive compounds that can influence fish growth, nutrient utilization, resistance to diseases and, as a natural source of antioxidants, have beneficial effects in overall health (Sáez et al., 2020; Sharma et al., 2019). In addition to these factors, their nutritional composition and sustainable nature have made them great candidates for alternative feed additives in fish diets. Fish larvae and other early stages of development are more susceptible to oxidative stress due to their high metabolic rate associated with very fast growth and other factors (Sharma et al., 2019). This leads to pressure on fish fitness and may cause high mortalities due to larvae´s limited capacity to respond to daily challenges derived from a complex environment and dietary changes. Here, the application of algae as a feed ingredient may have a positive influence on larvae’s early resistance, immune capacity and physiologic output.
Hatchery Feed & Management Vol 8 Issue 3 2020
Within the goal of a constant search for new alternative and sustainable ingredients for optimal fish health and performance the VALORMAR project has developed and tested new microdiets that may innovate the hatchery feeds market, bringing to the table diets that not only increase sustainable standards in a cost efficient manner but also have the potential to benefit fish development in the long term, resulting in more robust fish.
Micro- and macro- algae blends increase sole post-larvae performance A trial was performed to assess if the inclusion of algae blends (Fig. 1) had a positive effect on fish growth, immune and oxidative response on weaned post-larvae of Senegalese sole (Solea senegalensis). Larvae were reared in a recirculating system from 15 to 63 days after hatching (DAH), using an initial density of 3,000 larvae/m2. After weaning (27 and 28 DAH), co-feeding with Artemia and a commercial diet, 34 DAH post-