Factors affecting intensive larval rearing of striped mullet, Mugil cephalus

Abstract

Experiments were conducted on larvae of Mugil cephalus to determine onset of feeding, temporal changes in food selectivity, initial stocking density of larvae, rotifers and phytoplankton, and the effectiveness of enriching food organisms. Larvae were observed to possess rotifers in their gut at 70 h posthatch. A significant ( P < 0.01) difference in total length was detected between fed and unfed larvae by 84 h posthatch. All unfed larvae were dead 192 h after hatching. It was concluded that rotifers should be offered on Day 2 for proper propagation. Analysis of first-feeding larvae indicated that gut composition mirrors the food found in the water column. Larger food types predominated in the gut of older fish. Larvae fed enriched Artemia resulted in significantly higher growth ( P < 0.05) over those fed non-enriched Artemia or rotifers. Initial larval stocking densities were inversely correlated with survival ( r = −0.58, P < 0.01). Optimal initial stocking density was 10–20 larvae/l, 5–10 rotifers/ml, and phytoplankton at 500–700×10 3 cells/ml.