Myotis nigricans is an important species of insectivorous bat from the Vespertilionidae family, which is endemic of the Neotropics. Despite its wide distribution, no detailed study of the reproduction is found for this species. Thus, the aim of the present study was to evaluate and characterize morphological and morphometric variations of the female reproductive organs of M. nigricans during its different reproductive phases. Twenty adult females were collected, divided into four (4) sample groups, according to the reproductive status (nonreproductive, initial and advanced pregnancy and lactating), and submitted to anatomical, histological and morphometric analyses. The results demonstrated that the female reproductive organs of M. nigricans were composed of the ovaries, the uterus, the uterine tubes and the vagina, in addition to the mammary glands. The ovaries present a great number of interstitial glands and a small but persistent corpus luteum. Ovulation is simple, unilateral and non-preferential, possibly alternated in successive ovulations and may be sequential with the occurrence of postpartum estrus. The uterus is bicornuate, implantation is fundic and the placenta is chorioallantoic, discoidal and hemochorial. The vaginal epithelium is weakly keratinized and shows great disorganization during the periods of pregnancy and lactation.

中文翻译：

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vespertilionid bat nigricans 雌性生殖器官在不同生殖阶段的形态生理变化

Myotis nigricans 是一种重要的食虫蝙蝠，属于 Vespertilionidae 科，是新热带地区的特有种。尽管分布广泛，但没有对该物种的繁殖进行详细研究。因此，本研究的目的是评估和表征 M. nigricans 雌性生殖器官在其不同生殖阶段的形态学和形态学变化。收集了 20 名成年女性，根据生殖状态（非生殖、初始和晚期妊娠和哺乳期）分为四 (4) 个样本组，并进行解剖学、组织学和形态测量分析。结果表明，M. nigricans 的雌性生殖器官由卵巢、子宫、输卵管和阴道组成，除了乳腺。卵巢有大量的间质腺体和小而持久的黄体。排卵是简单的、单侧的和非优先的，可能在连续的排卵中交替出现，并且可能与产后发情的发生依次发生。子宫是双角的，着床是基部的，胎盘是尿囊绒毛膜、盘状和血绒毛膜。阴道上皮角质化较弱，在怀孕和哺乳期间表现出很大的紊乱。植入是胃底的，胎盘是尿囊绒毛膜、盘状和血绒毛膜。阴道上皮角质化较弱，在怀孕和哺乳期间表现出很大的紊乱。植入是胃底的，胎盘是尿囊绒毛膜、盘状和血绒毛膜。阴道上皮角质化较弱，在怀孕和哺乳期间表现出很大的紊乱。