Meeting Abstract
P2.36 Wednesday, Jan. 5 Assessment of development and immune status of northern leopard frogs (Rana pipiens) following polybrominated diphenyl ether (PBDE) exposure CARY, TL*; ORTIZ-SANTALIESTRA, ME; SCHMIDT, ND; KARASOV, WH; University of Wisconsin, Madison; University of Wisconsin, Madison; University of Wisconsin, Madison; University of Wisconsin, Madison tcary@wisc.edu
Polybrominated diphenyl ethers (PBDEs), a class of flame retardants, are peristant, bioaccumlative compounds found in biota worldwide. Concern regarding potential toxicity of PBDEs has spurred research to assess possible sublethal effects including those on growth, development and immune status. We tested for chronic effects of environmentally relevant dietary levels (0-634 ng/g) of PBDEs in frogs throughout larval development. Beginning at the free-swimming stage, Rana pipiens tadpoles were exposed to a technical PBDE mixture (DE-71) through metamorphic climax. Growth and development were delayed in all but the highest treatment. Time to metamorphic climax was on average delayed 22-36 days in DE-71 treatments compared to the control. Gross reproductive development was not significantly altered by DE-71, however, sex ratios were skewed in the lowest treatment with twice as many females as expected based on a 50:50 proportion. Inflammatory response was characterized by quantifying neutrophil recruitment from the vasculature into the tissues, and by measuring phagocytic activity using fluorescently-labeled 1µm beads. Neither leukocyte counts nor phagocytic activity were significantly different across treatment groups. A trend toward more highly phagocytic cells (i.e., cells that phyagocytosed more than 10 beads) was seen in the highest PBDE treatment group. From these data it appears that larval PBDE exposure may not have a strong influence on juvenile R. pipiens innate immune function. Adaptive immunity will also be considered, and results of treated frogs to produce specific antibodies measured by enzyme-linked immunosorbent assay will be forthcoming. Supported by UW Sea Grant Institute, NOAA, NA16RG2257/project R/EH-2.
