Gama-Flores José Luis, Huidobro-Salas María Elena, Sarma S S S, Nandini S
Carrera de Biología, National Autonomous University of Mexico, Tlalnepantla, State of Mexico, Mexico.
Laboratory of Aquatic Zoology, Division of Research and Postgraduate Studies, National Autonomous University of Mexico, Los Reyes, Tlalnepantla, State of Mexico, Mexico.
Dose Response. 2017 Aug 18;15(3):1559325817723732. doi: 10.1177/1559325817723732. eCollection 2017 Jul-Sep.
In this study, we quantified intergenerational, demographic variability of subjected to cadmium stress. Exposure of to cadmium (0.2, 0.3, and 0.4 mg/L as CdCl) through 4 consecutive generations revealed changes in demographic responses not only in survivorship variables but also in reproductive parameters. Long-term demographic responses varied differently, depending on the demographic trait and the concentration of heavy metal in the medium. With the exception of generation time, all life history traits were significantly and adversely influenced due to increase in Cd concentrations. The average life span of varied up to 40% depending on Cd level and the generation of exposure. The highest gross reproductive rates were recorded in controls, while the lowest (∼30% less) were recorded at the highest Cd level. Survival-weighted net reproductive rates were reduced by nearly 50% due to Cd toxicity. The rate of population increase per day of was also significantly affected (∼25%) by Cd as compared to controls. This cladoceran showed a dose-response to Cd toxicity with a significance in both magnitude and frequency of offspring production.
在本研究中，我们量化了镉胁迫下的代际人口统计学变异性。通过连续4代将（某种生物）暴露于镉（以CdCl计为0.2、0.3和0.4 mg/L）中，发现不仅生存变量，而且生殖参数的人口统计学响应都发生了变化。长期人口统计学响应因人口统计学特征和培养基中重金属浓度的不同而有所差异。除世代时间外，所有生活史特征均因镉浓度的增加而受到显著的不利影响。（某种生物）的平均寿命根据镉水平和暴露世代的不同而变化高达40%。最高的总生殖率记录在对照组中，而最低的（低约30%）记录在最高镉水平组。由于镉毒性，生存加权净生殖率降低了近50%。与对照组相比，（某种生物）每天的种群增长率也受到镉的显著影响（约25%）。这种枝角类动物对镉毒性表现出剂量反应，在后代产生的数量和频率上都具有显著性。
