Bioaccumulation and chronic toxicity of dietary l-selenomethionine in juvenile white sturgeon ( Acipenser transmontanus)

• Published in: Aquatic toxicology 2006-10, Vol.79 (4), p.401-409
• Main Authors: Tashjian, Diran H., Teh, Swee J., Sogomonyan, Arutyun, Hung, Silas S.O.
• Format: Article
• Language: English
• Subjects: Acipenser; Acipenser transmontanus; Agnatha. Pisces; animal behavior; Animal Feed - analysis; animal growth; Animal, plant and microbial ecology; Animals; Applied ecology; Behavior, Animal - drug effects; bioaccumulation; Biological and medical sciences; Body Composition - drug effects; dietary exposure; Dietary Supplements - toxicity; Ecotoxicology, biological effects of pollution; Fishes - metabolism; Fishes - physiology; Fundamental and applied biological sciences. Psychology; General aspects; Growth - drug effects; Histopathology; Kidney - drug effects; kidneys; Liver - drug effects; mortality; Motor Activity - drug effects; Selenium; Selenomethionine; Selenomethionine - administration & dosage; Selenomethionine - pharmacokinetics; Selenomethionine - toxicity; sturgeon; Survival Analysis; Swimming; Swimming activity; Time Factors; Toxicity; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution; water pollution; White sturgeon
• ISSN: 0166-445X; 1879-1514
• DOI: 10.1016/j.aquatox.2006.07.008

An 8-week growth trial was conducted to determine the sensitivity of white sturgeon ( Acipenser transmontanus) to the toxicological effects of elevated dietary selenium (Se). Juvenile white sturgeon were fed diets supplemented with Se in the form of l-selenomethionine (SeMet), resulting in dietary concentrations of 0.4, 9.6, 20.5, 41.7, 89.8, and 191.1 μg Se/g diet on a dry weight basis. Effects of dietary SeMet on survival, swimming activity, growth, whole-body proximate composition, tissue Se concentrations, and histopathology were determined. Sturgeon survival among treatment groups did not differ significantly with a mean survival rate of 99 ± 0.43% across all groups. A significant decrease ( p < 0.05) in swimming activity and growth rate was observed in sturgeon fed at or above 41.7 μg Se/g diet. Dietary SeMet concentrations were negatively correlated with whole-body protein and lipid content, but positively correlated with ash and moisture content. Selenium accumulated in the kidney, muscle, liver, gill, and plasma tissues in a dose-dependent manner. Histopathological alterations in the liver and kidney were observed in sturgeon fed above 20.5 μg Se/g diet. The threshold dietary Se toxicity concentration for white sturgeon was estimated to lie between 10 and 20 μg Se/g diet based on the histopathological alterations in the kidney. Research examining the consequences of elevated dietary Se concentrations on more sensitive life stages and the interactive effects of Se with other chemical or physical stressors are needed in order to determine if dietary threshold should be lowered to minimize the potential impacts of Se on white sturgeon in the San Francisco Bay-Delta.