The goal of our research is to further understand the relationship between the brine shrimp, Artemia franciscana, and the cestode tapeworms that infect them. The cestode cysts are ingested by brine shrimp, which serve as the intermediate host until the infected brine shrimp are consumed by their final host, Great Salt Lake water birds. The current method for determining the number of infected brine shrimp in different areas of the lake is limited to dissecting individual shrimp and searching for minute cysts under a microscope. Our goals are to develop a new, DNA-based method for quantifying the number of infected brine shrimp that is both more accurate and faster. and to provide an initial molecular phylogeny of the cestodes that infect the brine shrimp of Great Salt Lake.
We collected brine shrimp from three locations around the lake (Antelope Island, Black Rock State Park/State Marina, and the Spiral Jetty) over the span of several years. We then used PCR and gel electrophoresis to amplify and analyze a region of the cestode rRNA genes from DNA samples purified from individual brine shrimp as a marker for cestode infection. Our preliminary results indicate that the PCR method is working and accurately distinguishing between cestode-infected and uninfected brine shrimp. We have also detected differences in infection rates in different locations in Great Salt Lake. Also, our preliminary phylogenetic analysis of rRNA gene sequences places the Great Salt Lake brine shrimp infecting cestodes in the family of Hymenolepididae.