Barros M S, Morais D B, Araújo M R, Carvalho T F, Matta S L P, Pinheiro E C, Freitas M B
Ecophysiology Laboratory, Department of Animal Biology, Federal University of Viçosa, CEP 36570-000ViçosaMG, Brazil.
Braz J Biol. 2013 Aug;73(3):629-35. doi: 10.1590/S1519-69842013000300022.
Seasonal variation is a key factor regulating energy metabolism and reproduction in several mammals, including bats. This study aimed to track seasonal changes in the energy reserves of the insectivorous bat Molossus molossus associated with its reproductive cycle. Adult males were collected during the four neotropical annual seasons in Viçosa - MG, Brazil. Blood and tissues were collected for metabolic analysis and testes were removed for histology and morphometry. Our results show that liver and breast muscle glycogen concentrations were significantly lower in winter. The adiposity index was significantly higher in the fall compared to winter and spring. Seminiferous tubules were greater in diameter in animals captured in fall and winter, indicating a higher investment in spermatic production during these seasons. The percentage of Leydig cells was higher in summer compared to fall and winter. We suggest that M. molossus presents a type of seasonal reproduction with two peaks of testicular activity: one in fall, with higher sperm production (spermatogenesis), and another in summer, with higher hormone production (steroidogenesis). The metabolic pattern may be associated with reproductive events, especially due to the highest fat storage observed in the fall, which coincides with the further development of the seminiferous tubules.
季节变化是调节包括蝙蝠在内的多种哺乳动物能量代谢和繁殖的关键因素。本研究旨在追踪食虫蝙蝠皱唇犬吻蝠能量储备的季节性变化及其与繁殖周期的关系。在巴西米纳斯吉拉斯州维索萨的四个新热带年季节期间收集成年雄性蝙蝠。采集血液和组织进行代谢分析，并摘除睾丸进行组织学和形态测量。我们的结果表明，冬季肝脏和胸肌糖原浓度显著降低。秋季的肥胖指数显著高于冬季和春季。秋季和冬季捕获的动物的生精小管直径更大，表明在这些季节对精子产生的投入更高。夏季的莱迪希细胞百分比高于秋季和冬季。我们认为，皱唇犬吻蝠呈现出一种季节性繁殖类型，睾丸活动有两个高峰：一个在秋季，精子产生量较高（精子发生），另一个在夏季，激素产生量较高（类固醇生成）。代谢模式可能与生殖事件有关，特别是由于秋季观察到的最高脂肪储存量与生精小管的进一步发育相吻合。
