Consequently, identifying the optimum stocking density for a species may be critical factor is affecting growth and feed intake in cages. Increasing stocking density results in stress which leads to enhanced energy requirements causing reduced growth and food utilization. Stocking density is a major factor that affects fish growth under farmed conditions. Its quality features include an attractive body shape for selling as whole fish, a good processing yield and nutritional value, low fillet fat, excellent taste and firm texture, which distinguish meagre as a highly marketable fish species. This species is characterized by domestication ability, high tolerance to wide ranges of salinity (5% - 39‰) and temperature (13˚C - 28˚C) and exhibits high growth rates reaching 1.2 kg in less than 2 years. Meagre (Argyrosomus regius) become the world’s largest sciaenid fish that is widely distributed along the eastern Atlantic coast, including the Mediterranean sea as reported by. From the above results and the economic information of the study, it can be concluded that stocking density of 50 fish/m 3 of meagre exhibited the highest net profit and would seem to be the most desirable density in the system studied. Fish body composition% of moisture, protein, fat and ash were significantly (P ≤ 0.01) influenced by stocking density.
Harvest and production estimates increased with increasing stocking density. The best at the lowest stocking density, while, the total production and net production exhibited significantly the opposite trend. The results revealed that, mean final weight (g/fish), gain in weight, SGR (%per day), feed conversion ratio, protein efficiency ratio and total feed intake (g/fish) were significantly (P ≤ 0.01) influenced. Nine cages 24 m 3 each (4 × 6 × 1.5 m, long, width and height) were stocked with either 1200, 36 fish for each cage to give a stocking rate of 50, 150, and 250 fish/m 3 respectively and fish fed daily, slightly in excess of satiation to eliminate the possibility of food supply being a limiting factor to growth. A 10-week rearing trial was conducted in cages with average initial weight of 9.15 ± 0.2 g/fish and average initial length of 9.2 ± 0.02 cm/fish of meagre, Argyrosomus regius, to examine the effect of three stocking density on growth performances, production traits, feed utilization and body composition.
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