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

Abstract

The determination of exogenous enzyme contributions in live food is important in larval feeding. This study investigated the potential inhibitory effects and contributions of live foods used from 3 to 32 days after hatching (DAH) on protease activities of meagre (Argyrosomus regius) larvae (ML), using in vitro techniques. Enriched rotifer (R), Artemia nauplii (A0), and Artemia metanauplii (A1) were tested. The highest values of protease activities of ML were determined to occur at 7 DAH for the years 2013 and 2014. The lowest values were observed at 15 DAH in 2013 and at 20 DAH in 2014. Protease activities of R, A0, and A1 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. This situation was related to the inadequacy of protease contributions of live feeds , despite the highest protease value of larvae at 7 DAH (p < 0.05). The positive contributions of A1 live food on the protease activities of ML were significant (p < 0.05). The inhibitory effects and positive contributions of live foods on the survival and growth rates of ML should be taken into account for future studies considering the larvae of ML and other marine fish.

The Effect of Feeding with Chironomid and Artemia on Fatty Acids and Amino Acids Profiles in Persian Sturgeon (Acipenser persicus) Larvae

“…These findings underscore the significant effect of live foods on the FA composition of Persian sturgeon larvae. The nutritional performance of fish larvae in utilizing live food is influenced by several factors, including the biochemical composition of the live food [25,26]. The FA composition of larval body, when exposed to different live food sources, depends on both the profile of the live food and the fish's ability to digest and absorb these nutrients [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27].…”

“…The content of AA, especially EAA, is crucial for fish health and growth. The EAA composition in fish carcasses serves as an appropriate indicator to estimate and determine the nutritional requirements of fish [19][20][21][22][23][24][25][26][27][28][29][31][32][33][34][35][36][37][38][39][40]. The content and composition of AA in fish body depends on factors, such as nutrition, age, and season [41,42].…”

“…Since fish larvae are unable to synthesize EAA [43,44], they must obtain EAA through exogenous feeding. Differences in the AA content of food can cause a change in the AA composition of the larvae [18][19][20][21][22][23][24][25][26][27][28][29][31][32][33][34][35][36][37][38][39][40][41][42][43][44].…”

The changes in Alkaline, Neutral and Acid Protease Activities of Artemia Enriched with Commercial Emulsion and Different Additive Combinations

“…This information about the digestive physiology of larvae is important for the utilization of microdiets in the digestive system. According to the mentioned data, protease activities are indicators for determining the digestive ability of larvae (Diken, Demir & Naz, 2019).…”

“…Until now, protease activities of Artemia were determined in pH 8.0-8.5 substrate (Naz, 2008;Naz et al, 2011;Naz & Yufera, 2012;Haközü, 2014;Diken, Demir & Naz, 2016a;Diken, Demir & Naz, 2016b;Diken, Demir & Naz, 2019) except for Garcia-Ortega et al (1998) and Yenmis & Naz (2019). There is no available combined study on protease activities (alkaline, neutral and acid) and the biochemical compositions of Artemia enriched with the commercial emulsion (Red Algamac (RA)) and different additive combinations such as GroBiotic-A (GA), and Spirulina (SP).…”