Geology topics

P. Sharp

Publications and source records attributed to P. Sharp.

3 recordsLinked to original sources

USGS1996

Exposure of wild waterfowl to Mycoplasma anatis

We developed an ELISA procedure to assess the presence of M. Anatis-specific serum antibody in ducks. Sera from exposed and unexposed Pekin ducks (Anas platyrhynchos) were used to standardize tile ELISA and to establish reference ranges to classify ELISA results as exposed or not exposed. We conducted serological surveys of female waterfowl in the central and eastern United States between 1988 and 1992 to assess the frequency of exposure in wild waterfowl. Adult breeding mallards (Anas platyrhynchos), wintering mallards, and black ducks (Anas rubripes) had high prevalences of exposure to M. Anatis (25% to >80%). In comparison, none of the breeding adult canvasbacks (Aythya valisineria) had serum antibody levels indicating exposure. Approximately 50% of the juvenile mallards and black ducks were exposed to M. Anatis by 8 months of age, indicating high transmission rates among wild birds.

Journal of Wildlife Diseases↗

USGS1995

Effects of Mycoplasma anatis and cold stress on hatching success and growth of mallard ducklings

We inoculated game-farm mallard ( Anas platyrhynchos ) eggs and 1-day-old birds with Mycoplasma anatis to determine its effect on hatching success and growth rates of ducklings. Inoculations of eggs reduced hatching success, hatchling size, and duckling growth rates, compared to controls. Intratracheal inoculations of 1-day-old birds did not affect growth rates. Hatchlings and 1-day-old ducklings grew much slower for the first 7 to 10 days when raised at 17 to 19 C, compared to controls raised at 30 to 35 C. The effect of cold stress on growth was greater than the effect of M. anatis infection; we found no synergistic effects between cold stress and M. anatis infection.

North Dakota↗

USGS1995

The occurrence of mycoplasmas in selected wild North American waterfowl

We determined the prevalence of mycoplasma infection in breeding mallard ( Anas platyrhynchos ) and canvasback ( Aythya valisineria ) hens and their broods from the central United States (1988 to 1990); and wintering American black duck ( Anas rubripes ) and mallard hens from the eastern United States (1990 to 1993). Mycoplasmas were isolated by culturing tracheal swabs from 656 live birds and tissue samples from 112 dead waterfowl. Nine (18%) of 51 mycoplasma isolates were identified as Mycoplasma anatis ; M. anatis was recovered from four mallards, a black duck, and a gadwall ( Anas strepera ) duckling. Nineteen (37%) of 51 mycoplasma isolates were identified as Mycoplasma cloacale ; these isolates were obtained from mallard, canvasback, and black duck adults, and from a mallard duckling. Additional unspeciated mycoplasmas were isolated from mallards, black ducks, and one canvasback.

Journal of Wildlife Diseases↗