Physiologie de la Reproduction et des Comportements, UMR INRAE, CNRS, Université de Tours, IFCE, Nouzilly, France.
Centre de Biologie pour la Gestion des Populations, UMR INRAE, CIRAD, Institut Agro, IRD, Univ Montpellier, Montpellier, France.
Biol Lett. 2023 Feb;19(2):20220441. doi: 10.1098/rsbl.2022.0441. Epub 2023 Feb 22.
Most small rodent species display cyclic fluctuations in their population density. The mechanisms behind these cyclical variations are not yet clearly understood. Density-dependent effects on reproductive function could affect these population variations. The fossorial water vole ecotype, , exhibits multi-year cyclical dynamics with outbreak peaks. Here, we monitored different water vole populations over 3 years, in spring and autumn, to evaluate whether population density is related to male reproductive physiology. Our results show an effect of season and inter-annual factors on testis mass, plasmatic testosterone level, and androgen-dependent seminal vesicle mass. By contrast, population density does not affect any of these parameters, suggesting a lack of modulation of population dynamics by population density.
大多数小型啮齿动物物种的种群密度会呈现周期性波动。这些周期性变化的背后机制尚不清楚。生殖功能的密度依赖性效应可能会影响这些种群变化。穴居水鼠生态型表现出多年周期性动态，并有爆发高峰。在这里，我们在 3 年内，分春季和秋季，监测了不同的水鼠种群，以评估种群密度是否与雄性生殖生理有关。我们的研究结果表明，季节和年际因素对睾丸质量、血浆睾酮水平和雄激素依赖性精囊质量有影响。相比之下，种群密度不会影响这些参数中的任何一个，这表明种群密度对种群动态没有调节作用。
