SELENIUM ACCUMULATION IN CAPTIVE AMERICAN KESTRELS (FALCO-SPARVERIUS)FED SELENOMETHIONINE AND NATURALLY INCORPORATED SELENIUM

Male-female pairs of kestrels were maintained for 11 weeks on diets co ntaining 5 or 9 ppm selenium (Se) (dry weight) as seleno-L-methionine, or naturally incorporated Se in the form of mammals collected at Kest erson Reservoir, CA, USA. Selenium concentrations in blood and excreta of male and female kestrels within groups were similar. Near-maximal mean Se concentrations in blood were observed after the 5th week of tr eatment in the seleno-L-methionine-treated kestrels, and an approximat ely 1:1 ratio was observed between maximal blood concentrations and di etary concentrations. All treatment groups exhibited reduction of Se c oncentration in excreta, but not in blood, to baseline values 4 weeks after treatment ended. No birds were observed to exhibit signs of gene ral illness or Se toxicity during the study.