| The fact that the wild Atrina pectinata had decreased sharply because of over-catching at recent years has caused a mass of attentions. In order to provide basic information for artificial reproduction and culture, the influences of salinity, temperature and the food concentration on filtration, respiration, excretion and assimilation efficiency of the animals were studied and the scope for growth (SFG) were estimated. The results were as follows:1. Within the salinity range (21-41), the filtration rate increased with the increase of salinity and reached the highest value (0.83L/g/h) at salinity 31, then decreased with the increase of salinity, and reached the minimum value (0.43 L/g/h) at 41. Both the respiration and excretion rates increased first, then decreased with the increase of salinity, and got the minimum value at 31 and the highest value at 41. The assimilation efficiencies were between 36-51.33%, and acquired the maximum value at 36, the minimum value at 41. The scope for the growth (SFG) acquired the maximum value at salinity 31, but was negative at salinity 41. The SFGs between each pair of groups had no significant difference within salinity 26-36 range, indicating that the range is best suitable for the animal.2. At lower temperature phase (18-26℃), the filtration rate increased with the increase of temperature linearly, then increased tardily, but decreased rapidly when over 30℃. Within the temperature range (18-34℃), the filtration rates were between 0.28 and 0.82 L/g/h, and reached the minimum value at 18℃and the maximum value at 26℃. The respiration rate increased swiftly at the range 18-26℃, but tardily at the range 26-34℃, and reached the minimum value (260.82μg/h/g) at 18℃and the maximum value (585.90μg/h/g) at 34℃. The excretion rate were between 108.92 and 174.58μg/h/g, increased slowly with the increase of temperature at the beginning, but increased rapidly when temperature increasing from 22 to 26℃. The assimilation efficiency increased first, and then decreased with the increase of temperature, reaching the minimum value (42.33%) at 34℃and the maximum value (52.67%) at 22℃. The SFG increased with temperature increasing, reached the maximum value at 26℃, then decreased and became negative (-1.94 J/h/g) at 34℃. There were no significant differences for SFG among the temperatures 22, 26 and 30℃, indicating that the temperature range 22-30℃is best suitable for the animal.3. Within the food concentration range (0.85-11.84 mg POM/L), the filtration rate decreased with the increase of food concentration but the ingestion rate increased. The respiration rate had the trend of increase with the food concentration increasing, and increased slowly at the lower food concentration range (0.85-3.07 mg POM/L) and higher food concentration (6.42-11.84 mg POM/L), but rapidly at the range of 3.07-6.42 mg POM/L. The excretion rate increased gradually with the increase of food concentration. The assimilation efficiency decreased slowly with the food concentration increasing from 0.85 to 1.57 mg POM/L, but decreased rapidly over 1.57 mg POM/L. The SFG increased first and decreased with the increase of food concentration, reaching the maximum value of 10.91 J/g/h at 3.07 mg POM/L and the minimum of 1.40 J/g/h at 0.85 mg POM/L, with little variation while food concentration increasing from 3.07 to 6.42 mg POM/L, indicating that the food concentration range of 3.07 - 6.42 mg POM/L is best suitable for the animal.
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