EFFECTS OF DIETARY SELENIUM ON THE HEALTH AND SURVIVAL OF WINTERING LESSER SCAUP

• Main Author: Brady, Caroline M.
• Format: Text
• Language: unknown
• Published: Scholarship@Western 2009
• Subjects: Scaup; contaminants; Se; selenium; staging; wintering; health; survival; greater scaup
• Online Access: https://ir.lib.uwo.ca/digitizedtheses/3968; https://ir.lib.uwo.ca/context/digitizedtheses/article/7792/viewcontent/2023_02_25_Effects_of_Selenium_on_Health_and_Survival_of_Lesser_Scaup_OCR__2_.pdf

The acquisition and accumulation of selenium (Se) in the Lower Great Lakes (LGL) could be contributing to the continental decline of lesser and greater scaup (Aytha qffinis, A. marila). I exposed lesser scaup to background (0.8 ¿¿g/g), moderate (8.1 jUg/g) and high (20.7 jug/g) levels of dietary Se, measured survival rates and several indices of health in relation to hepatic Se concentrations. There was 100% survival of scaup exposed to Se for 10-weeks (staging duration) but birds in the high treatment group had lower lipid reserves. There was 93% survival after 23-weeks (wintering duration), but no differences among treatment groups in body composition or body mass. There were no effects of Se on indices of oxidative stress and cell- mediated immunity, but immuno-stimulatory effects on antibody production. Elevated Se in scaup on the LGL do not likely impact overall health and survival, and future research efforts should focus on alternative hypotheses for the scaup decline.