岩扇贝幼贝滤食率的基础研究

Fundamental research on filter-feeding rate of juvenile rock scallop

为了解岩扇贝Crassadoma gigantea幼贝的摄食率,采用静水法研究了在不同温度（6、10、14、18、22℃）、体质量（小、中、大3种规格）、饵料（新月菱形藻Nitzschia closterium、湛江等边金藻Isochrysis zhanjiangensis、亚心形扁藻Platymonas subcordiformis、小球藻Chlorella vulgaris）和饵料浓度（15×104、30×104、45×104、60×104、75×104cells/m L）条件下岩扇贝的滤食率及其昼夜节律。结果表明：温度、体质量、饵料种类和饵料浓度对岩扇贝幼贝滤食率有显著或极显著影响（P〈0.05或P〈0.01）;在试验温度和体质量范围内,幼贝单位体质量的滤食率均随温度和体质量的增加而增大;幼贝对4种单胞藻的滤食率±次为新月菱形藻〉湛江等边金藻〉亚心形扁藻〉小球藻,且对4种单胞藻的滤食率有显著性或极显著性差异（P〈0.05或P〈0.01）;当新月菱形藻浓度为30×104cells/m L时,幼贝的滤食率达到最大,极显著高于其他饵料浓度组（P〈0.01）;幼贝的滤食率存在显著的昼夜变化（P〈0.05）,一天中存在一个滤食高峰时段,即17：00~21：00[40.161×108cells/（g·h）],且显著高于其他时段（P〈0.05）,存在两个低峰时段,即9：00~13：00[32.496×108cells/（g·h）]和1：00~5：00[29.934×108cells/（g·h）],均显著低于其他时段（P〈0.05）。研究表明,岩扇贝的适温范围及对饵料的适应性较广,可作为中国重要扇贝引进品种加以培养。

The filter-feeding rate and feeding rhythm of juvenile rock scallop Crassadoma gigantea with various body weight（ dry software weight） of 0. 005 g（S ）,0.012 g（M） and 0. 026 g（L ） were studied under different al-gae including Nitzschia closterium, Isochrysis zhanjiangensis, Platymonas subcordiformis,and Chlorella vulgaris,at concentration of （ 15℃×104,30×104,45×104,60×104,and 75×104 cells/mL） and water temperatures of 6 ,1 0,14, 18 益,and 22 益 in order to understand the filter-feeding rate of juvenile rock scallop by a hydrostatic method. It was found that there were significant or very significant effects of temperature,body weight,alga species,and alga concentration on the filter-feeding rate of juvenile rock scallop （ P〈0. 05 or P〈0. 01）. The filter-feeding rate per unit body weight of juvenile rock scallop was shown to increase with warming temperature and increase in body weight within the test temperature range （ 6 -22℃）. The filter-feeding rate order of the scallop fed the four unicel-lular algae was expressed as N. closterium〉I. zhanjiangensis〉P. subcordiformis〉C. vulgaris,with significant or very significant differences among the four unicellular algae （ P 〈0.05 or P 〈0.01）. The maximum filter-feeding rate per unit body weight was observed at N. closterium concentration of 30×104 cellmL,significantly higher than those in other groups（ P 〈0. 01）. There were significant diurnal variation in filter-feeding rate （ P〈0.05） ,with peak at 17：00-21：00 [40. 161×108 cell（g·h）],significantly higher than those in other time（P 〈0.05） ,and two low values at 9：00-13：00 [32.496×108 cells/（g h）] ,and 1：00-5：00 [29. 934×108 cells/（g·h ） ] ,significant lower than thos in other time（ P〈0. 05）. The findings indicate that rock scallop is suitable for induction and culturedue to wide suitable water temperature range and food items.