The Inhibitory Effects and Positive Contributions of Live Foods on Protease Activities of Meagre, Argyrosomus regius (Asso 1801) Larvae in vitro Assay

The aim of this study was to gather preliminary data about the potential inhibitory effects and contributions of live foods used from 3 to 32 days after hatching (DAH) in routine feeding protocols on protease activities of meagre, Argyrosomus regius (Asso 1801) larvae, using in vitro techniques. Enriched rotifer, Artemia nauplii and Artemia metanauplii were tested in the present study. The highest values of protease activities of meagre larvae at 7 DAH in 2013 and 2014 years were established. The lowest values at 15 DAH in 2013 and at 20 DAH in 2014 were observed. Protease activities of enriched rotifer, Artemia nauplii, and Artemia metanauplii were 21.76±0.31, 36.00±1.48–29.33±0.93, and 416.44±19.7–403.53±11.85 U/mg protein, respectively (p< 0.05). The highest inhibitions of live foods were observed at 7 DAH. The positive contributions of live food Artemia metanauplii’s on protease activities of meagre larvae were significant (p< 0.05). The inhibitory effects and positive contributions of live foods on survival and growth rates of meagre larvae, should be taken into account in meagre and other marine fish larvae’s future studies. Cysteine protease activities of Artemia sp. should be investigated to provide the higher growth and survival ratio from the feeding protocols used in marine fish larvae.