Cooperative Fish and Wildlife Research Units Program: Oregon
Education, Research and Technical Assistance for Managing Our Natural Resources

Schuster, C.J., T. Kreul, E. Al-Samarrie, J.T. Peterson, J.L. Sanders, M.L. Kent. Progression of infection and detection of Pseudoloma neurophilia in zebrafish Danio rerio Hamilton by PCR and histology. Journal of Fish Diseases


Pseudoloma neurophilia is an important threat to the zebrafish (Danio rerio) model, as it is the most common infectious agent found in research facilities. This parasite can cause clinical disease, but more importantly is a causative agent of non-protocol induced variation in research utilizing zebrafish as an animal model. In this study, we tracked the progression of infection using PCR and histological diagnostic tests. The first experiment compared the application of diagnostic tools for detection of P. neurophilia and showed that whole-body analysis by qPCR (WB-qPCR) can be a standardized process and is comparable to previously published assays using neural tissue. We also evaluated the course of infection in experimentally infected fish, revealing that WB-qPCR is much more sensitive than histology. the parasite was detectable as early as 4 days post exposure (dpe) with WB-qPCR, whereas it was undetected by histology until 92 dpe. In this study, we also added a second slide for histologic analyses, and this increased detection in our combined data set from experiments from 24% to 26%.