Meagre is one of the Mediterranean region most important aquaculture species due to its impressive growth in captivity compared to other farmed fish species. One of the most challenging bottlenecks to reduce meagre larvae production costs is early weaning protocols. Two feeding protocols were developed for meagre considering the reducing of Artemia period during early weaning. Growth, survival and aspects of digestive physiology were studied during the first 25 days.
Two early weaning strategies were tested, that used microdiets from mouth opening (2 days post hatching – DAH) until 30 DPH . First strategy rotifers were used between 2 and 10 DAH and no Artemia was used ( MDROT); Second strategy rotifers, were used between 2 and 10 DAH, and Artemia was used between 8 and 17 DAH ( MDART). These strategies were compared with the standard feeding protocol (CTRL) used at EPPO, that consist in feeding rotifers from mouth opening until 10 DAH, introduce microdiet at 8 DAH to be used until 30 DAH, whereas Artemia is introduced at 8 DAH and used until 22 DAH. Rotifers, grown on w3Yeast 60 (Bernaqua, Belgium), and Artemia (Instar II) (SepArtTechnology™, INVE) were both enriched with Red pepper™.. WINFAST microdiets from SPAROS, Lda (Olhão, Portugal) were used in the experiment
Fish samples were collected along experimental period for biometry, survival, histology and quantification of digestive enzymes actitivies.
The larvae length growth and dry weight of CTRL were significantly (p < 0.05) increased by the time than MDART and MDROT. The 30 DAH larvae survival %. recoded no significant (p >0.05) differnces between all treatments. The 30 DAH larvae recoded highest significant (p < 0.05) length growth performance results except 25 DAH was significantly (p < 0.05) higher than 30 DAH in specific growth rate.
Fish larvae digestive physiology was negatively affected by the weaning strateagies when compared to control strategy. Fish larvae development status at each sampling was manily responsible for the observed differences.