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USGS · 5221062

Reproduction in eastern screech-owls fed selenium

Stanley N. Wiemeyer·David J. Hoffman
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Abstract

Raptors are occasionally exposed to excessive selenium from contaminated prey, but the effects of this exposure on reproduction are unknown. Therefore, we fed captive eastern screech-owls ( Otus asio ) diets containing 0, 4.4, or 13.2 ppm (wet wt) added selenium in the form of seleno-DL-methionine. Adult mass at sacrifice and reproductive success of birds receiving 13.2 ppm selenium were depressed ( P < 0.05) relative to controls. Parents given 4.4 ppm selenium produced no malformed nestlings, but femur lengths of young were shorter ( P = 0.015) than those of controls. Liver biochemistries indicative of oxidative stress were affected ( P < 0.05) in 5-day-old nestlings from parents fed 4.4 ppm selenium and included a 19% increase in glutathione peroxidase activity, a 43% increase in the ratio of oxidized glutathione (GSSG) to reduced glutathione (GSH), and a 17% increase in lipid peroxidation. Based on reproductive effects relative to dietary exposure, sensitivity of eastern screech-owls to selenium was similar to that of black-crowned night-herons ( Nycticorax nycticorax ) but less than that of mallards ( Anas platyrhynchos ).

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BibTeXRIS

Stanley N. Wiemeyer, David J. Hoffman. 1996. Reproduction in eastern screech-owls fed selenium. https://doi.org/10.2307/3802232

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