Turnover of stable isotopes due to growth and metabolism in zebrafish, Danio rerio

Stable isotope ratios of carbon (13C/12C), nitrogen (15N/14N) and sulfur (34S/ 32S) in animal tissues can be used as tracers of the nutrient sources of organisms' diets and determining trophic interactions in ecosystems. The rate at which an organism takes up the isotopic signature of its food is correlated with its growth rate and/or metabolism. Hence unless baseline isotopic turnover rates are known, the isotopic signature of a consumer may lead to misinterpretation of predator-prey relationships. Laboratory studies provide isotopic turnover rates of organisms under controlled conditions, which serve as models for understanding the rates at which organisms in the field isotopically incorporate new diets. This study examines the isotopic turnover rates of carbon, nitrogen and sulfur in response to a dietary switch in zebrafish. At the observed turnover rate, the turnover half times of carbon, nitrogen and sulfur would be approximately 55, 147 and 60 days, respectively.