Screening of enzyme activity for assessing the condition of larvae in the seven-band grouper Epinephelus septemfasciatus and devil stinger Inimicus japonicus

Abstract

Abstract:We conducted screening tests whether enzyme activity is applicable as a biomarker for assessing the physiological condition of marine fish larvae. Two trials of rearing experiments until 5 days after hatching (DAH) of the seven-band grouper Epinephelus septemfasciatus and one trial until 10 DAH of devil stinger Inimicus japonicus were conducted using three different rearing-tank proportions (shallow tank, S; intermediate tank, I; and deep tank, D) with water volume of 100 L at an aeration rate of 50 mL/min. We determined survival, surface death, growth and enzyme activities (trypsin, esterase and alkaline phosphatase). Two species exhibited their highest survival and lowest surface death in D tank. Significant and negative correlation between survival on 5 DAH and alkaline phosphatase activity on 0 DAH was found in the seven-band grouper. The same correlation was found between survival on 10 DAH, and trypsin and alkaline phosphatase activity on 1 DAH in devil stinger. We concluded that particular enzymes activity is candidate for assessing the conditions of marine fish larvae.

Feeding effect of selenium enriched rotifers on larval growth and development in red sea bream Pagrus major

“…Fertilized fish eggs of red sea bream Pagrus major were obtained from a local fish farmer in this study. Eggs were transferred into 100-L polycarbonate tanks at eggs/L following the procedure of Ruttanapornvareesakul et al, 2010. In each feeding regime, four polycarbonate tanks containing 100 L of 34-ppt artificial sea water with each type of Chlorella (non-or Se-fortified one) at 5×10 5 cells/mL, were prepared with aeration at a rate of 50 mL/min.…”

Application of the minute monogonont rotifer proales similis de Beauchamp in larval rearing of seven-band grouper epinephelus septemfasciatus

“…The tryptic enzyme activity of seven-band grouper larvae was measured using a methods that followed that of Ruttanapornvareesakul et al (2010) with slight modifications of Ueberschar (1995) and Araujo et al, (2001). Five larvae were sampled Arg-MCA) using a repeating pipet and syringe tip (Nichimate Stepper), and then were vortexed well using a tube mixer (Ms1 Minishacker, Kika Works (Asia) Sdn.…”