A New Perspective on Mental Health Assessment in Laboratory Animals: Stress Response Monitoring Based on Hair Characteristics

doi:10.12300/j.issn.1674-5817.2025.166

Abstract

Abstract:

The mental health management of laboratory animals is a critical factor in ensuring the reliability of scientific research data. However, due to the subtle nature of mental state alterations and the limitations of current assessment methods, the mental health of laboratory animals is often overlooked by researchers. Therefore, there is an urgent need to explore a new, objective, simple, and practical method for evaluating mental health. Stress, as a primary factor inducing alterations in the mental state of animals, can influence experimental results across multiple research fields through the neuroendocrine-immune network. This paper first elucidates the necessity of mental health management in laboratory animals from three perspectives: factors contributing to stress, neural mechanisms of stress, and research areas affected by stress. It highlights that excluding animals with abnormal mental states before experiments can enhance the efficiency and reproducibility of biomedical studies. Second, this paper briefly summarizes existing methods for assessing the health of laboratory animals, pointing out that approaches such as behavioral tests and metabolomics have many limitations in evaluating stress responses. Existing methods struggle to meet the demand for simple, objective, and non-invasive assessment methods in animal management. Therefore, this paper focuses on hair, a biological sample with the advantages of cumulative information and non-invasive collection, and systematically describes the theoretical basis and technological advances in using hair characteristics as indicators of stress responses from three perspectives: hair traits, the levels of substances in hair, and artificial intelligence (AI). It proposes and supports an innovative technical pathway that combines hair traits with AI-based image analysis, with the aim of offering an improved solution for non-invasive and objective stress assessment, while providing theoretical support for improving the health management system of laboratory animals.

Key words: Laboratory animals, Mental health management, Stress, Hair, Artificial intelligence

CLC Number:

Q95-33

LI Hongman,CHEN Yutong,SHI Yingpei,et al. A New Perspective on Mental Health Assessment in Laboratory Animals: Stress Response Monitoring Based on Hair Characteristics[J]. Laboratory Animal and Comparative Medicine, 2026, 46(4): 553-563. DOI: 10.12300/j.issn.1674-5817.2025.166.

Figures/Tables 3

References 67

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参数 Parameters		表现 Manifestations	相关机制 Related mechanisms	参考文献 References
毛发性状 Hair characteristics	颜色	变白	黑素细胞干细胞耗竭	[49]
	数量	减少	毛发提前进入休止期并脱落	[42]
	粗细	变细	抑制毛囊干细胞活性，新生毛发变细	[45]
	质地	干燥、脆弱、易断	皮脂合成减少、角蛋白交联断裂、鳞片脱落	[50]
毛发物质含量 Levels of substances in hair	皮质酮	含量升高	降解透明质酸、蛋白聚糖等毛囊内关键物质	[45]
	角蛋白	表达减少	毛发强度和弹性降低	[50]
	促炎因子	表达增加	毛囊退化、抑制毛发生长	[51]
	生长因子	表达减少	毛发生长减缓	[52]
	代谢物质	代谢物谱改变	糖代谢、氨基酸代谢等代谢途径发生改变	[48]
	微量元素	含量减少	结构蛋白、黑色素合成障碍	[53]

参数 Parameters		表现 Manifestations	相关机制 Related mechanisms	参考文献 References
毛发性状 Hair characteristics	颜色	变白	黑素细胞干细胞耗竭	[49]
	数量	减少	毛发提前进入休止期并脱落	[42]
	粗细	变细	抑制毛囊干细胞活性，新生毛发变细	[45]
	质地	干燥、脆弱、易断	皮脂合成减少、角蛋白交联断裂、鳞片脱落	[50]
毛发物质含量 Levels of substances in hair	皮质酮	含量升高	降解透明质酸、蛋白聚糖等毛囊内关键物质	[45]
	角蛋白	表达减少	毛发强度和弹性降低	[50]
	促炎因子	表达增加	毛囊退化、抑制毛发生长	[51]
	生长因子	表达减少	毛发生长减缓	[52]
	代谢物质	代谢物谱改变	糖代谢、氨基酸代谢等代谢途径发生改变	[48]
	微量元素	含量减少	结构蛋白、黑色素合成障碍	[53]