Staining and resin embedding of wholeDaphniasamples for micro-CT imaging

Abstract

Abstract Micro-CT imaging is a powerful tool for generating high resolution, isotropic three-dimensional datasets of whole, small model organisms that are useful for qualitative and quantitative analysis. D. magna , one of the most common ecological model organisms used for toxicity testing and evaluation of environmental stressors, could benefit from this imaging method for enhancing whole-organism phenotype assessment. This protocol details the steps involved in Daphnia sample preparation for micro-CT imaging: euthanasia, fixation, staining, and resin embedding. The resulting 3D reconstructions of samples imaged using synchrotron micro-CT revealed histological (microanatomic) features of organ systems, tissues, and cells in the context of the entire organism at sub-micron resolution. 3D histology and renderings enabled by this imaging method could contribute to morphometric analysis of any tissue or organ system for both descriptive and hypothesis testing studies.