Chen Wenting, Liu Xiaotong, Zhu Qifei, Liu Junjie, Ullah Abd, Liu Yihong, Wei Jinjin, Khan Muhammad Zahoor, Wang Changfa
College of Agriculture and Biology, Liaocheng University, Liaocheng 252000, China.
Vet Sci. 2025 Sep 1;12(9):846. doi: 10.3390/vetsci12090846.
Chestnuts are keratinized skin structures found on equine limbs, but their characteristics in donkeys remain poorly understood. This study aimed to characterize chestnut morphology and histology in Dezhou donkeys and examine correlations with phenotypic traits.
A cross-sectional study was conducted on 347 Dezhou donkeys (0.3-15 years, 79-419 kg). Chestnut dimensions were measured using precision calipers, and correlations were analyzed with age, body weight, limb measurements, and thoracolumbar vertebral counts. Histological analysis compared chestnut tissue with adjacent normal skin using standard H&E staining protocols.
Donkeys exclusively possessed chestnuts on forelimbs, predominantly showing regular geometric configurations. Histologically, chestnut tissue exhibited marked hyperkeratosis (>30 cellular layers vs. 4-6 in normal skin), widespread melanocyte distribution throughout the epidermis, and complete absence of cutaneous appendages. In group A, strong positive correlations were observed between chestnut width and age (r = +0.527, < 0.01), body weight (r = +0.538, < 0.01), and limb measurements (r > +0.589 < 0.01). No significant correlations existed with vertebral numbers. In group B Dezhou donkeys older than 2 years, the length and width of the forelimb chestnuts showed the strongest significant correlation with right forelimb measurements, while no significant correlations were observed with other variables (age, body weight, and hindlimb measurements).
Chestnuts in Dezhou donkeys represent specialized integumentary structures with unique histological features and strong correlations with somatic development. These findings support their potential utility as biometric markers for individual identification and indicate coordinated developmental regulation with overall growth patterns.
蹄叉是马属动物四肢上的角质化皮肤结构，但对驴蹄叉的特征了解甚少。本研究旨在描述德州驴蹄叉的形态和组织学特征，并探讨其与表型性状的相关性。
对347头德州驴（0.3 - 15岁，体重79 - 419千克）进行横断面研究。使用精密卡尺测量蹄叉尺寸，并分析其与年龄、体重、肢体测量值和胸腰椎计数的相关性。组织学分析采用标准苏木精 - 伊红染色方案，将蹄叉组织与相邻正常皮肤进行比较。
驴仅在前肢有蹄叉，主要呈现规则的几何形态。组织学上，蹄叉组织表现出明显的角化过度（>30个细胞层，而正常皮肤为4 - 6层），黑色素细胞广泛分布于整个表皮，且完全没有皮肤附属器。在A组中，蹄叉宽度与年龄（r = +0.527，P < 0.01）、体重（r = +0.538，P < 0.01）和肢体测量值（r > +0.589，P < 0.01）之间存在强正相关。与椎体数量无显著相关性。在B组2岁以上的德州驴中，前肢蹄叉的长度和宽度与右前肢测量值的相关性最强，而与其他变量（年龄、体重和后肢测量值）无显著相关性。
德州驴的蹄叉代表具有独特组织学特征且与躯体发育密切相关的特殊皮肤结构。这些发现支持了它们作为个体识别生物标志物的潜在用途，并表明其与整体生长模式存在协调的发育调控关系。
