| Present study is designed to determine the effects of stocking density, salinity, temperature, dietary protein, dietary carbohydrate, and sodium chloride on survival and growth of juvenile Litopenaeus vannamei, together with an analysis of the bioenegetic mechanisms involved. The primary results of these studies are listed below.1. The effect of stocking densities (12.04, 24.08, 48.16, 144.49, 240.81, 337.13, 433.46, 529.78, 626.11 individuals-m-2) on L vannamei: I. The survival for densities of 12.04, 24.08 and 48.16 individuals-m-2 are significantly higher than for density of 626.11 individuals-m-2 . II. The specific growth rate for densities of 12.04 and 24.08 individuals-m-2 are significantly higher as compared with other treatments.2. The effect of salinity (0.5, 5,10,15,20,25, 30 and 35%o) on L. vannamei: I. The specific growth rate, food consumption, food efficiency and absorption efficiency are highest at 20%, while the survival is highest at 35%. II. The specific growth rate, food consumption and absorption efficiency are lowest at 0.5%.3. The effect of salinity (0.2, 11, 21 and 31 %o) and temperature (20, 24, 28 and 32 C) on L. vannamei: I. All shrimps survive at 11, 21 and 31% irrespective of temperature; at 0.2%, the survival decreases with increasing temperature from 20 C to 28C, then plateaus at 32C. II. At all levels of temperature with increases of salinity within the range tested, the specific growth rate or food consumption gradually increases, reaching the maximum value, and thereafter declines. III. At 0.2%, the specific growth rate, food consumption or absorption efficiency exhibits an increasing trend from 22 C, reaching the maximum value at 28 C, then shows a decline up to 32 C with increasing temperature, while at salinities of 11, 21 and 31%, the specific growth rate, food consumption or absorption efficiency exhibits an increasing trend. IV. Food efficiency generally decreases in response to increasing temperature within the salinity range tested.4. The effect of salinity (0.2, 1, 2, 4, 8 and 16%o) and dietary carbohydrate levels (15.47, 29.15 and 41.00%) on L. vannamei: I. No shrimps survive at 0.2% at theend of the experiment irrespective of dietary carbohydrate (CBH). II. At each dietary CBH level, the specific growth rate and food consumption generally increase with increasing salinity within the range of 1-16%o. III. At 16%o groups, the specific growth rate are similar in shrimps fed 29.15% and 15.47% dietary CBH, whereas those fed 41.00% dietary CBH exhibit the significantly lower value; at 2-8%o groups, the specific growth rate in shrimps fed 29.15% dietary CBH are significantly higher as compared with other treatments; at l%o groups, the specific growth rate in shrimps fed 29.15% and 41.00% dietary CBH are not significantly different, but are significantly higher as compared with other treatment.5. The effect of temperatures (22, 27 and 32癈) and dietary carbohydrate levels (15.47, 29.15 and 41.00%) on L vannamei: I. At each dietary carbohydrate (CBH) level, the specific growth rate, food consumption and absorption efficiency generally increase, whereas food efficiency decreases with increasing temperature within the range of 22-32 C. II. At temperatures of 22, 27 and 32 C, the specific growth rate and food consumption are the highest in shrimps fed 29.15% CBH, closely followed by those fed 15.47% CBH, those fed 41.00% CBH had the lowest values.6. The effect of salinity (0.5, 8, 16 and 25%o) and dietary protein levels (26.59, 35.18 and 45.31%) on L. vannamei: I. At 0.5%o, the survival decreases with increasing dietary protein level, and grows well at salinities above 8%o. II. At three dietary protein levels, the highest specific growth rate, food consumption, gross conversion efficiency and net conversion efficiency are obtained at 8%o and 16%, which generally decrease with increased or decreased salinity. III. At 0.5%, the shrimps fed three dietary protein levels exhibit no significant differences in the specific growth rate; at 8-25%o, the...
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