de Matos André Silva, Kugelmeier Tatiana, Guimarães Diva Anelie de Araújo, da Silva Klena Sarges Marruaz
Instituto de Ciência e Tecnologia em Biomodelos, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil.
Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brasil.
Anim Reprod. 2022 Apr 22;19(1):e20210068. doi: 10.1590/1984-3143-AR2021-0068. eCollection 2022.
Lab animals, such as Guinea pigs (), are crucial for scientific development, as they play an important role in the development and quality control chain of vaccines and drugs distributed by the Brazilian public health system. Investigating their biological and physiological parameters is fundamental to raise and keep these animals, so the handling of the facilities that hold them can be updated whenever new information comes up, with the well-being of the animals and alignment with the 3 Rs in mind. In the search for understanding reproductive aspects of Guinea pigs, the present study had the main goal of studying puberty by means of estrous cycle analysis in short-haired Guinea pigs. Guinea pigs have a vaginal occlusive membrane that covers the vaginal orifice. Its rupture takes place gradually and naturally, moments before labor and during estrus. The present study followed 42 females as for the presentation of the vaginal occlusive membrane. Once the membranes ruptured spontaneously, a swab was collected to study vaginal cytology. Membrane rupture was observed in 39 females; six females showed membrane rupture with less than 21 days of age (17 to 21 days). Twenty-three females were characterized as being in estrus due to cytology showing a prevalence of anucleated superficial cells. One of these females was younger than 21 days old. The opening of the vaginal occlusive membrane took place most frequently in intervals between 17 and 18 days, and the membrane remained open between one and three consecutive days. It was possible to follow three cycles of membrane opening on six females. The present study showed the need to adapt handling guidelines for kept in research animal facilities. The early age of puberty imposes the need of separate the female daughters from their fathers at 16 days old.
实验动物，如豚鼠，对科学发展至关重要，因为它们在巴西公共卫生系统分发的疫苗和药物的研发及质量控制链中发挥着重要作用。研究它们的生物学和生理学参数对于饲养和维持这些动物至关重要，这样在有新信息出现时，饲养它们的设施的管理就能得到更新，同时要考虑到动物的福祉并符合3R原则。在探索豚鼠生殖方面的过程中，本研究的主要目标是通过对短毛豚鼠发情周期的分析来研究青春期。豚鼠有一层阴道闭锁膜覆盖阴道口。它的破裂在分娩前和发情期时会逐渐自然发生。本研究跟踪了42只雌性豚鼠阴道闭锁膜的情况。一旦膜自发破裂，就采集拭子来研究阴道细胞学。在39只雌性豚鼠中观察到膜破裂；6只雌性豚鼠在21日龄以下（17至21天）时膜破裂。23只雌性豚鼠因细胞学显示无核表层细胞占优势而被判定处于发情期。其中一只雌性豚鼠年龄小于21天。阴道闭锁膜的开口最常发生在17至18天的间隔内，且膜连续开放一至三天。有可能跟踪6只雌性豚鼠的三个膜开口周期。本研究表明需要调整研究动物设施中豚鼠的饲养指南。青春期的早期到来使得有必要在雌性豚鼠16日龄时将其与父亲分开。
