Characterization of the prion protein gene in axis deer () and implications for susceptibility to chronic wasting disease.

Axis deer () occur both in captivity and free-ranging populations in portions of North America, but to-date, no data exist pertaining to the species' susceptibility to CWD. We sequenced the prion protein gene () from axis deer. We then compared axis deer PrP sequences and amino acid polymorphisms to those of CWD susceptible species.

An evaluation of three sampling methods to monitor a digenetic trematode Centrocestus formosanus in a spring-fed ecosystem.

Centrocestus formosanus is a digenetic trematode from Asia that parasitizes multiple hosts and is a concern in the Comal River, Texas, USA, because of its negative effects on the endangered fountain darter Etheostoma fonticola. To determine a practical sampling method to monitor C. formosanus in the Comal River, we evaluated three sampling methods using wild-caught fish, caged fish reared in the laboratory, and cercariometry.

Misting and nitrogen fertilization of shoots of a saltmarsh grass: effects upon fungal decay of leaf blades.

We conducted a 12-week field manipulation experiment in which we raised the nitrogen availability (ammonium sulfate fertilization to roots) and/or water potential (freshwater misting) of decaying leaf blades of a saltmarsh grass (smooth cordgrass, Spartina alterniflora) in triplicate 11-m plots, and compared the manipulated plots to unmanipulated, control plots. The ascomycetous fungi that dominate cordgrass leaf decomposition processes under natural conditions exhibited a boosting (>2-fold) of living standing crop (ergosterol content) by misting at the 1 st week after tagging of senescent leaves, but afterwards, living-fungal standing crop on misted blades was equivalent to that on control blades, confirming prior evidence that Spartina fungi are well adapted to natural, irregular wetting. Misting also caused 2-fold sharper temporal declines than control in instantaneous rates of fungal production (ergosterol synthesis), 5-fold declines in density of sexual reproductive structures that were not shown by controls, and 2-fold higher rates of loss of plant organic mass.

Water potential of standing-dead shoots of an intertidal grass.

Dead stems and leaves of smooth cordgrass (Spartina alterniflora Loisel.) undergo substantial fungal decay in the standing position. We conducted a series of experiments to determine the probable range of water availabilities that cordgrass-fungal decomposers experience; we determined the effects of duration of wetting and drying, site on shoots, leaching of osmotica, and stage of decomposition on water potential (ψ) of cordgrass shoots.