Effects of salinity and temperature on survival, growth, and energy budget of juvenile Litopenaeus vannamei

A 4x4 factorial experiment was conducted to determine the effects of salinity (0.2 parts per thousand, 11 parts per thousand, 21 parts per thousand, and 31 parts per thousand.) and temperature (20 degrees C, 24 degrees C, 28 degrees C, and 32 degrees C) on survival, growth, and energy budget of juvenile Litopenaeus vannamei with the initial wet body weight of 0.274-0.283 g. The experiment lasted for 5 wk. The results showed that all shrimp survived at 11 parts per thousand, 21 parts per thousand, and 31 parts per thousand, irrespective of temperature; at 0.2 parts per thousand, survival decreased with increasing temperature from 20 degrees C to 28 degrees C, then plateaued at 32 degrees C. At all levels of temperature with increases of salinity within the range tested, specific growth rate or food consumption gradually increased, reaching the maximum value and thereafter declined. At 0.2 parts per thousand, specific growth rate, food consumption, or apparent digestibility coefficient exhibited an increasing trend from 22 degrees C, reaching the maximum value at 28 degrees C, then showed a decline up to 32 degrees C with increasing temperature, whereas at salinities of 11 parts per thousand, 21 parts per thousand, and 31 parts per thousand; specific growth rate, food consumption, or apparent digestibility coefficient exhibited an increasing trend. By contrast, feed efficiency generally decreased in response to increasing temperature within the salinity range tested.