Abstract：
Different tissues are used for stable isotope analysis in cetacean investigations. However, variation in the isotopic composition of tissues with different turnover rates has been reported for cetaceans. To better understand stable carbon and nitrogen isotopes (δ13C and δ15N) in skin compared to other tissues, this study assessed the isotopic variation among the liver, muscle, and skin of Guiana dolphins (Sotalia guianensis), as well as the influence of sex on these variations. No differences were found in δ13C among male tissues, but females showed lower values in the liver compared to muscle and skin. Differences in δ15N were observed among all tissues, with different variation patterns for males and females. Four females were distinguished from males and other females by their 13C depletion in all tissues and δ15N variation pattern. We conclude that skin and muscle may be equivalent in δ13C values for Guiana dolphins. The multiple-tissue analysis brings new insights into their feeding ecology and provides background for stable isotope analysis using non-destructive sampling techniques in small cetaceans.
摘要：
在鲸类研究中，不同的组织用于稳定同位素分析。然而,已经报道了鲸目动物具有不同转换率的组织同位素组成的变化。为了更好地了解与其他组织相比，皮肤中稳定的碳和氮同位素（δ13C和δ15N），这项研究评估了肝脏的同位素变异，肌肉，和圭亚那海豚（Sotaliaguianensis）的皮肤，以及性别对这些变化的影响。在雄性组织中没有发现δ13C的差异，但女性的肝脏价值低于肌肉和皮肤。在所有组织中观察到δ15N的差异，男性和女性的变异模式不同。四只雌性与雄性和其他雌性的区别在于它们在所有组织中的13C消耗和δ15N变异模式。我们得出的结论是，圭亚那海豚的皮肤和肌肉的δ13C值可能相等。多组织分析为它们的摄食生态学带来了新的见解，并为在小型鲸目动物中使用非破坏性采样技术进行稳定同位素分析提供了背景。
