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11.
Ocean acidification leads to changes in physiological and immune responses of bivalves, but the eff ect on the immune enzyme activities of the Manila clam, R uditapes philippinarum, when the pH is lower than the normal value has not been studied in detail. In this study, experiments were conducted to determine how pH(7.4, 7.7, 8.0) affects the immune enzyme activities in the gill and hemocytes of the Manila clam. Membrane stability and phagocytosis increased with decrease of pH from 8.0 to 7.7 and then decreased at pH 7.4. The total protein content in the hemocytes and gills decreased with decreasing pH. Lysozyme content in the hemocytes increased with decreasing pH, and the diff erences were significant among the different pH groups(P 0.05). Adenosine triphosphatase activity at pH 7.4 was significantly higher than in the other two groups, but no significant diff erence was observed between pH 7.7 and 8.0. Catalase activity decreased from pH 8.0 to 7.7 and then increased at pH 7.4, and the dif ferences were significant among the experimental groups( P 0.05). These findings provide valuable information about the immune response of R. philippinarum to reduced water pH and insights for future research investigating exposure of bivalves to elevated CO_2 conditions.  相似文献   
12.
Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wild population were used. Shell width (X1), shell height (X2), umbo-callus height (X3), body width (X4), operculum length (X5), operculum width (X6), body weight (Y1) and soft-tissue weight (Y2) were measured, and the correlation coefficient matrix calculated. Morphological traits were used as independent variables and weight traits as dependent variables for path coefficient analysis. Path coefficients, correlation indices and determination coefficients were also determined. Results indicate that the correlation coefficients associated with each morphological and weight trait were all highly significant (P〈0.01). After deleting redundant independent variables, the following optimum multiple regression equations were obtained using stepwise multiple regression analysis: Y1=-29.317+0.362X2+0.349X4+ 1.190)(5 for body weight; and Y2=-17.292+0.166X1+0.171X2+0.703X5, for soft-tissue weight. Operculum height had the highest positive direct correlation with both body weight and soft-tissue weight, which was in accordance with the test results obtained from determinate coefficient analysis. The indication of high genetic correlations between weight traits and morphological traits will provide valuable information for G. reiniana breeding programs.  相似文献   
13.
Based on stable isotope analysis, we characterized the dietary regime of the Manila clam Ruditapes philippinarum inhabiting intertidal areas along the Liaodong Peninsula, Northern China. Samples, including particulate organic matter (POM; n =30), benthic microalgae (BMI; n =30) and R. philippinarum (n =60), were collected from six sampling sites displaying the same ecological conditions. Of the two primary food sources, POM was more depleted in δ 13C (?20.61‰ to ?22.89‰) than BMI was (?13.90‰ to ?16.66‰). With respect to 15N, BMI was more enriched (2.90‰ to 4.07‰) than POM was (4.13‰ to 5.12‰). The δ 13C values of R. philippinarum ranged from ?18.78‰ to ?19.35‰ and the δ 15N values from 7.96‰ to 8.63‰, which were intermediate between the POM and BMI values. In a two-source isotope mixing model, we estimated the relative contributions of POM and BMI to the diet of R. philippinarum to be 74.2% and 25.8%, respectively. We conclude that R. philippinarum feeds mainly on POM, and BMI is also an important supplemental food source in intertidal areas.  相似文献   
14.
于2009年8月以菲律宾蛤仔海洋橙品系的全同胞子一代和子二代上选10%的个体作为亲本,通过建立近交组合(F22、F33)、杂交组合(F23、F32)和设置对照组(C22、C33),研究了两个近交世代的杂交效应及近交效应,以提高菲律宾蛤仔海洋橙品系的表型性状。结果表明,杂交使幼虫和稚贝的生长性状得到了部分改良,但存活性状...  相似文献   
15.
以蛤仔橙色全同胞家系为材料,采用建立近交组和设置对照组的方法,进行了近交对橙色家系的生长和存活性状影响的研究。结果表明:在整个实验期间,橙色家系壳长生长都慢于对照组,除60日龄外,其它各日龄二者壳长差异显著(P<0.05);橙色家系存活率高于对照组,除360日龄外,其它各日龄二者存活率均差异显著(P<0.05)。橙色家系生长的近交衰退率范围为5.38%—26.57%,平均值为15.48%±6.44%,但存活性状在各日龄没有出现近交衰退。在330日龄时,对橙色家系的形态学性状进行正态分布检验,结果表明:近交使橙色家系内出现小型化个体。本研究为通过建立家系选育蛤仔橙色新品系的育种方法奠定了一定的理论基础。  相似文献   
16.
在实验室条件下,设置12、17、22、27和32℃五个温度梯度和12、17、22、27和32五个盐度梯度,研究了不同温度和盐度对大竹蛏(Solen grandis)耗氧排氨的影响。结果表明:随着温度的升高耗氧率先降低再逐渐升高,在温度为22℃时为最小值1.571 mg/(g·h);排氨率先降低后升高再降低,在温度17℃时为最小值0.127 mg/(g·h)。随着盐度增加耗氧率先升高后降低,在盐度22时达到最大值3.106 mg/(g·h),排氨率先降低再升高,在盐度为27时为最小值为0.145 mg/(g·h)。在盐度32时,不同温度的O:N范围是5.525~79.037。在温度12℃时,不同盐度下的O:N范围是4.378~16.755。不同温度下耗氧率Q_(10)变化范围为1.054~2.421,排氨率的Q_(10)变化范围是0.748~1.256。研究结果为进一步完善大竹蛏的人工养殖技术提供参考。  相似文献   
17.
于2008年6月,以大连野生型蛤仔为材料,采用巢式设计即1个雄性亲本与3个雌性亲本交配的方式建立了菲律宾蛤仔15个半同胞家系(A,B,…,O)和45个全同胞家系(A1,A2,A3,…,O1,O2,O3)。对各家系的壳长、壳宽、壳高、鲜重等各项指标进行了方差分析和多重比较。结果表明,3、4、5月龄,菲律宾蛤仔45个全同胞家系的表型性状具有显著差异,且各月龄的差异趋势基本一致。5月龄时,从其生长性状上看,家系F2、G2、G3表现出明显的生长优势,壳长分别提高28.43%、24.72%、30.53%,壳宽分别提高21.14%、22.3%、25.58%,壳高分别提高30.88%、26.96%、25.25%,鲜重分别提高50.00%、68.42%、44.12%。从其存活上看,家系E3的四个表型性状在全同胞家系中最小,但存活数量最多为2269粒,表现出很强的抗逆性;具有生长优势的家系F2存活个数最少仅为43粒,抗逆性相对最差。从其产量上看,家系N3、I1、E3、C1、N1、G2产量较高,分别比平均产量提高了77.8%、75.61%、75%、69.45%、53.96%、50.19%。综合以上各项指标家系G2、G3、N3、E3、I1、C1、N1可作为优良的家系育种材料,在下一步育种工作中可以利用家系选择及家系杂交的方法对7个家系进行遗传改良。  相似文献   
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