大鸨生殖系统形态结构初步研究

Histological Structure of Reproductive Systems of Great Bustard(Otis tarda)

通过对7只不同年龄♂♀体大鸨生殖系统的形态结构解剖发现:大鸨雄性生殖系统由睾丸、附睾、输精管和交配器组成,无真正的阴茎,而具有阴茎体。睾丸一对,黑色、长形、豆状,右侧在前,左侧睾丸略大于右侧。大鸨睾丸从孵化出壳到性成熟无颜色变化,只是体积和重量增长。附睾在幼年时不明显,而在成体发情期时显著,呈前端较大的纺锤形。输精管外观为半透明、黑色弯曲的线状,沿输尿管向后延伸至泄殖腔壁形成突起,即输精管乳头;雌性生殖系统由卵巢和输卵管组成。卵巢和输卵管仅左侧正常发育,右侧输卵管退化为—短白色盲管。左卵巢因卵泡发育而呈葡萄串状。左输卵管在性未成熟时为一直形细管,性发育成熟后有较多弯曲,管径也增大,可分为漏斗部、壶腹部、峡部、子宫和阴道5部分。

Reproductive systems of seven great bustards, males and females, of different ages were studied histologically.The male reproductive system was composed of testis, epididymis, vas deferens and copulatory apparatus, no genuine phallus, but only a phalluslike organ; testis： a pair, long, black, bean- like; right one in the front, smaller than the left one; no change in color from hatching to sexual mature, increase in volume and weight only; epididymis not noticeable in infancy, becoming visible in adulthood, during estrus; spindle- formed with the front enlarged; vas deferens black in color, semi- wansparent and curly linear, stretching back along ureter to the wall of cloaca, forming a protrusion, known as papillar ductus deferens.Female reproductive system was composed of ovary and oviduct, only the one on the left side developed nortnaUy, the left degenerated into a white, short caecum; the left ovary developed like a cluster of grapes due to growth of follicles; the left oviduct was a tiny tube before sexual maturation, when matured, developed into five parts： infundibulum, ampulla, isthmus, uterus and vagina.