PDF(Pubmed)
Abstract：
Omega-3 long-chain polyunsaturated fatty acids (n3-LCPUFAs) are produced primarily in aquatic ecosystems and are considered essential nutrients for predators given their structural role in vertebrates\' cerebral tissues. Alarmingly, with urbanization, many aquatic animals now rely on anthropogenic foods lacking n3-LCPUFAs. In this study undertaken in Newfoundland (Canada), we tested whether recent or longer term diet explains the cerebral fatty acid composition of ring-billed gulls (Larus delawarensis), a seabird that now thrives in cities. During the breeding season, cerebral levels of n3-LCPUFAs were significantly higher for gulls nesting in a natural habitat and foraging on marine food (mean ± s.d.: 32 ± 1% of total identified fatty acids) than for urban nesters exploiting rubbish (27 ± 1%). Stable isotope analysis of blood and feathers showed that urban and natural nesters shared similar diets in autumn and winter, suggesting that the difference in cerebral n3-LCPUFAs during the breeding season was owing to concomitant and transient differences in diet. We also experimentally manipulated gulls\' diets throughout incubation by supplementing them with fish oil rich in n3-LCPUFAs, a caloric control lacking n3-LCPUFAs, or nothing, and found evidence that fish oil increased urban nesters\' cerebral n3-LCPUFAs. These complementary analyses provide evidence that the brain of this seabird remains plastic during adulthood and responds to short-term dietary changes.
摘要：
Omega-3长链多不饱和脂肪酸（n3-LCPUFA）主要在水生生态系统中产生，并且由于其在脊椎动物的脑组织中的结构作用，被认为是捕食者的必需营养素。令人震惊的是,随着城市化，许多水生动物现在依赖缺乏n3-LCPUFA的人为食物。在加拿大纽芬兰进行的这项研究中，我们测试了近期或长期饮食是否可以解释环嘴海鸥（Larusdelawarensis）的大脑脂肪酸组成，一种现在在城市里生长的海鸟。在繁殖季节，在自然栖息地筑巢和在海洋食物上觅食的海鸥的大脑中n3-LCPUFA的水平明显高于利用垃圾的城市筑巢者（27±1％）。血液和羽毛的稳定同位素分析表明，城市和自然的老人在秋季和冬季有着相似的饮食，表明繁殖季节大脑n3-LCPUFA的差异是由于饮食中的伴随和短暂差异。我们还通过在整个孵化过程中补充富含n3-LCPUFA的鱼油来实验性地操纵海鸥的饮食，缺乏n3-LCPUFA的热量控制，或者什么都没有，并发现了鱼油增加城市老人大脑n3-LCPUFAs的证据。这些补充分析提供了证据，表明这种海鸟的大脑在成年期保持可塑性，并对短期饮食变化做出反应。
