Shimamoto Tatsuki
Department of Veterinary Nursing and Technology, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-8602, Japan.
Gen Comp Endocrinol. 2022 Jan 15;316:113944. doi: 10.1016/j.ygcen.2021.113944. Epub 2021 Nov 24.
In various mammalian species, there has been an increase in the use of hair cortisol analysis to evaluate long-term stress. This trend is because of some advantages relative to the standard tools, such as hormone analysis using blood, urine, or feces. Here, I carried out assay validation and adrenocorticotrophic hormone (ACTH) challenge to measure long-term stress in Pallas's squirrel Callosciurus erythraeus. In addition, I investigated the effects of sex, body condition, season, and reproductive conditions on hair cortisol concentrations (HCC) in free-living individuals. The assay validation was reported in this study. Hair cortisol concentrations in squirrels given repeated ACTH injections were significantly higher than those that received a single-ACTH injection and a saline injection. I found a negative effect of body condition on adult HCC. In contrast, body condition had a positive effect on HCC in juveniles. I found no effects of other factors in either adult or juvenile squirrels. Furthermore, although I investigated whether reproductive conditions, such as pregnancy, lactation, and non-breeding in females or testis size in males, affected HCC, I found that there were no effects of reproductive conditions. This study validated the assay and utility of hair cortisol analysis to assess long-term stress, and continuous investigation of the relationship between HCC and fitness is important for determining whether hair cortisol analysis is a reliable method for estimating population health in Pallas's squirrels.
在各种哺乳动物物种中，使用毛发皮质醇分析来评估长期应激的情况有所增加。这种趋势是由于相对于标准工具（如使用血液、尿液或粪便进行激素分析）具有一些优势。在此，我对赤腹松鼠（Callosciurus erythraeus）进行了检测验证和促肾上腺皮质激素（ACTH）激发试验以测量长期应激。此外，我研究了性别、身体状况、季节和繁殖状况对自由生活个体毛发皮质醇浓度（HCC）的影响。本研究报告了检测验证情况。多次注射ACTH的松鼠的毛发皮质醇浓度显著高于单次注射ACTH和注射生理盐水的松鼠。我发现身体状况对成年松鼠的HCC有负面影响。相比之下，身体状况对幼年松鼠的HCC有正面影响。我发现其他因素对成年或幼年松鼠的HCC均无影响。我还研究了繁殖状况，如雌性的怀孕、哺乳和非繁殖状态或雄性的睾丸大小是否会影响HCC，但发现繁殖状况并无影响。本研究验证了毛发皮质醇分析评估长期应激的检测方法及实用性，持续研究HCC与健康状况之间的关系对于确定毛发皮质醇分析是否是评估赤腹松鼠种群健康的可靠方法至关重要。
