中国超细毛羊(甘肃型)胎儿皮肤毛囊发育及其形态结构

Study on Fetal Skin Hair Follicle Development and Morphology of China Super-Fine Merino (Gansu Type)

【目的】探究中国超细毛羊(甘肃型)毛囊的组织结构与毛囊形态发生过程,为超细毛羊毛囊发育的分子调控机制研究奠定组织学基础。【方法】采用冰冻组织切片技术制作横切、纵切切片,在显微镜下观测照相。【结果】中国超细毛羊(甘肃型)毛囊结构包括连接组织鞘、外根鞘、内根鞘、毛干和毛球部。在胎龄87 d时初级毛囊发生形成毛芽,在初级毛囊基底部可见次级毛囊的囊泡结构。胎龄102 d时次级毛囊开始再分化。到胎龄138 d时,初级毛囊基本发育成熟。胎龄87—147 d,初级毛囊密度随胎龄增长逐渐降低,次级毛囊密度随胎龄增长逐渐升高,在胎龄102—117 d时次级毛囊增长迅速,在胎龄117 d时达到最大值(232.8±12.44)个/mm2,胎龄126 d时次级毛囊/初级毛囊比值达到最大值9.96。【结论】在胎龄84 d时初级毛囊开始发生,胎龄87 d时次级毛囊开始发生,胎龄102 d时在原始次级毛囊颈部隆突部开始再分化出再分化次级毛囊,胎龄108 d时原始次级毛囊大量再分化,胎龄138 d时大部分初级毛囊和部分次级毛囊发育成熟;次级毛囊再分化是影响毛囊密度的最主要因素,它能有效地增加毛囊密度,提高羊毛细度。

[ Objective ] This study aims to research the organizational structure of China Super-Fine Merino hair follicles and hair follicle morphogenesis process, which will lay a histological basis for molecular regulation mechanism of Super-fine Merino hair follicle development. [Method] Tissue frozen section was conducted by embryonic skin of China Super-Fine Merino and the results were taken photography under a microscope. [Result] Results showed that the follicle structure of Super-fine Merino sheep consists of connective tissue sheath, outer root sheath, inner root sheath, hair shaft and hair bulb sections, as other mammals. Primary hair follicle occurred on 87th day of fetal period, vesicle structure of the secondary follicle could be found at the bottom of the primary hair follicle. At gestational 138 d, the primary basic hair follicle was mature. From gestational 87 d to 147 d, the density of primary follicle was gradually decreased and the density of secondary follicle was increased as the gestational age growing, meanwhile the density of primary follicle reached its maximum value （232.8±12.44） （per mm^2） at gestational 117 d. The gestationalSecondary Follicles to Primary Follicles ratio （S/P ratio） reached the maximum （9.96） at gestational age 126 d. [Conclusion] Primary follicles began to occur at 84 d of gestational age, and secondary hair follicle began to occur at 87 d of gestational age, gestational age 102 d in the original the secondary follicles neck bulge began regeneration to secondary-derived follicles, most of primary follicles and some of secondary hair follicle had matured. The differentiation of secondary hair follicle is a key factor which affected the density of hair follicle; it can effectively increase the density of hair follicle and improve the quality of the wool.