Changes in the physiological performance and energy metabolism of an estuarine mysid (Mysidopsis bahia) exposed in the laboratory through a complete life cycle to the defoliant DEF

The Missing Biomarker Link: Relationships Between Effects on the Cellular Energy Allocation Biomarker of Toxicant-Stressed Daphnia Magna and Corresponding Population Characteristics

“…For TBT-Cl and LAS, the total carbohydrate content of the test organisms was affected at toxicant concentrations lower than those affecting the lipid reserves. The overall importance of the lipid or carbohydrate metabolism relative to the protein metabolism for toxicant-exposed invertebrates has been described by several researchers who demonstrated an increased O:N ratio (ratio between oxygen consumed and the nitrogen excreted) with increasing toxicant concentrations [19]. These conclusions are supported by the observations of Knowles and McKee [20], who showed that glycogen and lipid content of D. magna exposed to CdCL 2 for 4 d was affected at 2.1 g/L, whereas protein content was only affected at 4.3 g/L.…”

“…In general, the methodologies used to quantify energy budgets have been, until now, based on quantifying changes in individual energy reserve compounds such as glucose and glycogen or on changes in the energy consumption as determined by oxygen consumption and nitrogen excretion rates [19]. In general, the methodologies used to quantify energy budgets have been, until now, based on quantifying changes in individual energy reserve compounds such as glucose and glycogen or on changes in the energy consumption as determined by oxygen consumption and nitrogen excretion rates [19].…”

The missing biomarker link: Relationships between effects on the cellular energy allocation biomarker of toxicant‐stressed Daphnia magna and corresponding population characteristics

“…Several authors have used physiological energetics of aquatic organisms to quantify the energy metabolism related to their development, feeding behavior, ecological efficiency, or their response to toxic exposure. In general, the methodologies used to quantify energy budgets have been, until now, based on quantifying changes in individual energy reserve compounds such as glucose and glycogen or on changes in the energy consumption as determined by oxygen consumption and nitrogen excretion rates [19]. In the present study, results from a new biomarker are presented.…”

“…However, the same authors concluded that for chlordecone and fenvalerate, the protein content was the biochemical endpoint most predictive for effects on organismal reproduction. The overall importance of the lipid or carbohydrate metabolism relative to the protein metabolism for toxicant‐exposed invertebrates has been described by several researchers who demonstrated an increased O:N ratio (ratio between oxygen consumed and the nitrogen excreted) with increasing toxicant concentrations [19]. The observations of the present study with D. magna further corroborate the conclusions of Elendt [21], who suggested that from an energetic point of view the lipid fraction in D. magna is more important than the glycogen content.…”

From organisms to populations: Modeling aquatic toxicity data across two levels of biological organization

“…Linking organism‐level to population‐level effects is difficult when multiple organism‐level effects are occurring, and it often is difficult to discern the contributions of organism‐level effects when present in combination. For example, in life‐cycle tests using the mysid, Americamysis bahia , changes in reproduction and survival frequently are observed simultaneously, and effects occur at different magnitudes [16,17]. In such cases, decreased λ values may result from decreased survival, reproduction, or a combination of the two [8].…”