Investigating Susceptibility of Tadpoles to ranavirus (FV3) with Exposure to Polychlorinated Biphenyl
Victoria Angeles ’20, Chicago, Illinois
Amphibian populations have declined dramatically in many areas of the world, and environmental pollution is one factor implicated in these declines. The polychlorinated biphenyl-126 (PCB-126) is a legacy environmental pollutant known to cause immune disruption, which could lead to increased vulnerability to disease. We tested whether Lithobates pipiens tadpoles exposed to polychlorinated biphenyl (PCB-126) would have increased susceptibility to a ranavirus, Frog Virus 3 (FV3). As an indicator of susceptibility, we measured morphometrics of exposed tadpoles, because infected tadpoles would have to allocate energy to fighting the infection instead of growth. We predicted that the growth of the tadpoles would decrease if exposed to both PCB and FV3. Additionally, we needed to determine whether or not the tadpoles were actually infected with the ranavirus. We extracted DNA from the kidneys of preserved tadpoles and used polymerase chain reaction (PCR) and gel electrophoresis to identify FV3 DNA in the kidneys. There were no differences in any growth parameters or organ mass ratios measured between our PCB-treated and PCB + FV3-treated tadpoles. However, there was a change in intestinal length compared to control for PCB + FV3 treated tadpoles. As the amount of FV3 virus increased, there was a decrease in intestinal length for both control and PCB. We also only found FV3 DNA in three of our FV3-exposed tadpoles. At this time, we are unable to conclude whether or not PCB exposure increased tadpole susceptibility to FV3.