Comparative serum fatty acid profiles of captive and free-ranging cheetahs (Acinonyx jubatus) in Namibia

Cheetahs (Acinonyx jubatus) are highly specialised large felids, currently listed as vulnerable on the IUCN red data list. In captivity, they are known to suffer from a range of chronic non-infectious diseases. Although low heterozygosity and the stress of captivity have been suggested as possible causal factors, recent studies have started to focus on the contribution of potential dietary factors in the pathogenesis of these diseases. Fatty acids are an important component of the diet, not only providing a source of metabolisable energy, but serving other important functions in hormone production, cellular signalling as well as providing structural components in biological membranes. To develop a better understanding of lipid metabolism in cheetahs, we compared the total serum fatty acid profiles of 35 captive cheetahs to those of 43 free-ranging individuals in Namibia using gas chromatograph mass spectrometry. The unsaturated fatty acid concentrations differed most remarkably between the groups, with all of the polyunsaturated and monounsaturated fatty acids, except arachidonic acid and hypogeic acid, detected at significantly lower concentrations in the serum of the free-ranging animals. The influence of age and sex on the individual fatty acid concentrations was less notable. This study represents the first evaluation of the serum fatty acids of free-ranging cheetahs, providing critical information on the normal fatty acid profiles of free-living, healthy individuals of this species. The results raise several important questions about the potential impact of dietary fatty acid composition on the health of cheetahs in captivity.

猎豹（Acinonyx jubatus）为高度专业化的大型猫科动物，目前被列入国际自然保护联盟红色名录中的易危物种。在人工饲养环境下，猎豹常患多种慢性非传染性疾病。尽管低异质性及圈养压力被视为可能的致病因素，但近期研究开始关注潜在饮食因素对这些疾病发病机制的影响。脂肪酸是饮食中的重要组成部分，不仅提供可代谢的能量来源，而且在激素生成、细胞信号传导以及生物膜的结构成分中发挥其他重要作用。为了更好地理解猎豹的脂质代谢，我们利用气相色谱质谱法，将35只圈养猎豹的总血清脂肪酸谱与43只在纳米比亚自由奔跑的个体进行了比较。不饱和脂肪酸在两组之间的浓度差异最为显著，除花生四烯酸和地衣酸外，所有多不饱和和单不饱和脂肪酸在自由奔跑动物血清中的浓度均显著降低。年龄和性别对个体脂肪酸浓度的影响并不显著。本研究首次评估了自由奔跑猎豹的血清脂肪酸，为该物种自由生活、健康个体的正常脂肪酸谱提供了关键信息。研究结果引发了对饮食中脂肪酸组成对圈养猎豹健康潜在影响的几个重要问题。