Abstract
Aplysia californica is widely used as an animal model of neurophysiology. Within genomic databases for Aplysia, an RNA virus in the order Nidovirales was recently discovered. Samples within the databases suggest the virus is neurotropic. No pathology associated with the virus has been identified. This thesis presents direct analysis of the virus within sampled Aplysia tissues, using Real-Time Quantitative PCR. Egg batches, young animals (<5 months), old animals (>10 months), and wild-caught animals were analyzed. All tissues sampled showed evidence of infection with only a small portion of samples qualifying as virus negative, indicating a broad tissue tropism and wide-ranging infection among hatchery and wild populations. Only two egg batches and three young animals were entirely virus negative. In old and wild animals, the abdominal and head ganglia and the heart were the most infected tissues. The I-4 muscle, anterior tentacle, and gut were the least infected tissues. This supports the virus being neurotropic. Comparing young and old animals, the viral load increased significantly with age. Nearly all eggs sampled were infected, suggesting vertical transmission as one means of infection.