PDF(Pubmed)
Abstract：
The dietary habits of seals play a pivotal role in shaping management and administration policies, especially in regions with potential interactions with fisheries. Previous studies have utilized various methods, including traditional approaches, to predict seal diets by retrieving indigestible prey parts, such as calcified structures, from intestines, feces, and stomach contents. Additionally, methods evaluating nitrogen and stable isotopes of carbon have been employed. The metabolomics approach, capable of quantifying small-scale molecules in biofluids, holds promise for specifying dietary exposures and estimating disease risk. This study aimed to assess the diet composition of five seal species-Arctocephalus pusillus pusillus, Lobodon carcinophaga, Ommatophoca rossii, and Arctocephalus tropicalis 1 and 2-by analyzing stomach and colon contents collected from stranded dead seals at various locations. Metabolite concentrations in the seal stomach and colon contents were determined using Nuclear Magnetic Resonance Spectroscopy. Among the colon and stomach contents, 29 known and 8 unknown metabolites were identified. Four metabolites (alanine, fumarate, lactate, and proline) from stomach contents and one metabolite (alanine) from colon contents showed no significant differences between seal species (p>0.05). This suggests that traces of these metabolites in the stomach and colon contents may be produced by the seals\' gut microbiome or derived from other animals, possibly indicating reliance on fish caught at sea. Despite this insight, the cause of death for stranded seals remains unclear. The study highlights the need for specific and reliable biomarkers to precisely indicate dietary exposures across seal populations. Additionally, there is a call for the development of relevant metabolite and disease interaction networks to explore disease-related metabolites in seals. Ultimately, the metabolomic method employed in this study reveals potential metabolites in the stomach and colon contents of these seal species.
摘要：
海豹的饮食习惯在制定管理和行政政策中起着举足轻重的作用，特别是在与渔业有潜在互动的地区。以前的研究已经使用了各种方法，包括传统方法，通过检索不可消化的猎物来预测海豹的饮食，如钙化结构，从肠道，粪便,和胃内容物。此外,评估氮和碳的稳定同位素的方法已被采用。代谢组学方法，能够量化生物流体中的小尺度分子，有希望指定饮食暴露和估计疾病风险。本研究旨在评估五种海豹的饮食组成————————————————————————————————————————————————————————————————————————————————————————洛博顿癌，Ommatophocarossii,通过分析从不同位置的死海豹中收集的胃和结肠内容物，以及热带牛头蛇1和2。使用核磁共振波谱法测定密封胃和结肠内容物中的代谢物浓度。在结肠和胃内容物中，鉴定出29种已知代谢物和8种未知代谢物。四种代谢物（丙氨酸，富马酸盐,乳酸，和脯氨酸）来自胃内容物和来自结肠内容物的一种代谢物（丙氨酸）在海豹物种之间没有显着差异（p>0.05）。这表明胃和结肠内容物中这些代谢物的痕迹可能由海豹肠道微生物组产生或来自其他动物，可能表明依赖在海上捕获的鱼。尽管有这样的见解，滞留海豹的死因尚不清楚。该研究强调需要特异性和可靠的生物标志物来准确指示海豹种群的饮食暴露。此外,人们呼吁开发相关代谢物和疾病相互作用网络，以探索海豹中与疾病相关的代谢物。最终,本研究中使用的代谢组学方法揭示了这些海豹的胃和结肠内容物中潜在的代谢产物。
