Oxidative stress is considered the main physiological mechanism involved in short- and long-term life histories, operating through the progressive deterioration of tissues, with consequences in the reproductive performance, growth patterns, aging, and survival. Besides, the Antarctic Peninsula environmental change, registered in the last decades, makes essential the antioxidant status knowledge of fauna and flora to optimize current management plans to protect Antarctic wildlife. Therefore, the present study aimed to investigate the differences between the oxidant-antioxidant status in adults and chicks´ blood of the skuas Stercorarius antarcticus and Stercorarius maccormicki. Through spectrophotometric techniques, the enzyme activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione S-transferase (GST) as well as the level of total glutathione (TG), total protein (TP), lipid peroxidation (LPO), and protein oxidation (PO) were measured. The adults of both species showed higher TG levels than the chicks. S. antarcticus adults were characterized by showing high GST activity and the highest total protein (TP) levels. Instead, S. maccormicki adults showed high levels of oxidative damage (PO and LPO) and high CAT activity. On the other hand, the chicks of both species were typified by the augmented SOD activity compared to those registered in adults. In turn, S. maccormicki chicks had increased GPx activity. Considering the multiple factors that affect the antioxidant status of both skua species, the information reported, herein, is a first promising dataset that would allow giving reference values for them.

中文翻译：

---

来自南极洲 25 de Mayo (King George) 岛波特半岛的 Stercorarius maccormicki 和 Stercorarius antarcticus 的血液抗氧化状态

氧化应激被认为是涉及短期和长期生活史的主要生理机制，通过组织的逐渐退化起作用，对生殖性能、生长模式、衰老和存活产生影响。此外，在过去几十年中记录的南极半岛环境变化使得动植物的抗氧化状态知识必不可少，以优化当前保护南极野生动物的管理计划。因此，本研究旨在调查 Stercorarius antarcticus 和 Stercorarius maccormicki 的成虫和雏鸡血液中氧化-抗氧化状态之间的差异。通过分光光度技术，超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx）、和谷胱甘肽 S-转移酶 (GST) 以及总谷胱甘肽 (TG)、总蛋白 (TP)、脂质过氧化 (LPO) 和蛋白氧化 (PO) 的水平进行了测量。两个物种的成虫都显示出比雏鸡更高的 TG 水平。S. antarcticus 成虫的特点是表现出高 GST 活性和最高的总蛋白 (TP) 水平。相反，S. maccormicki 成虫表现出高水平的氧化损伤（PO 和 LPO）和高 CAT 活性。另一方面，与成年注册的那些相比，这两个物种的小鸡都具有增强的 SOD 活性。反过来，S. maccormicki 雏鸡的 GPx 活性增加。考虑到影响这两种贼鸥物种抗氧化状态的多种因素，本文报告的信息是第一个有希望的数据集，可以为它们提供参考值。