Meeting Abstract
Handling of animals is conditional when performing experiments. When using stress-related gene transcription as a molecular marker in stress studies, it is important to consider handling in order to potentially contribute to optimal experimental design. Acartia tonsa is a well-studied calanoid copepod concerning basic physiological and ecotoxicological responses besides argued as a relevant live feed for fish larvae in the aquaculture sector. In order to create optimal experimental designs for transcriptional analysis on A. tonsa it is important to know the potential effect caused by handling on stress-related genes. Nauplii and adult individuals of A. tonsa were placed on a plankton filter up to 10 minutes to represent a typical handling situation. As a positive stress control, a salinity shock (from a regulator salinity of 35 to 5) for up to 10 minutes was used. The negative stress control consisted of non-handled individuals. The copepods were stained with neutral red in order to examine mortality caused by handling. Nauplii survival percentage was close to 100% after 10 min of handling, while the adults exhibited a survival of just 45-61% with the same treatment. Since the adults are more sensitive towards handling, we decided to focus on the adults solely in the following gene transcriptional analysis. For the transcriptome analysis (RNAseq) individuals of A. tonsa were grown from eggs to adults in culture flasks at optimal conditions in order to avoid any handling or stress. The aim of this study is to create awareness of the potential handling effects in studies involving transcriptional gene analysis. We want to examine the effects in the calanoid copepod, A. tonsa, and identify genes involved in handling stress.
