Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA 92521, USA.
Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA 92521, USA; Neuroscience Graduate Program, University of California, Riverside, CA 92521, USA.
Behav Processes. 2024 Aug;220:105060. doi: 10.1016/j.beproc.2024.105060. Epub 2024 Jun 22.
In many biparental mammals, such as California mice (Peromyscus californicus), fathers display affiliative behavior toward unfamiliar infants whereas reproductively naïve adult males show highly variable responses. Sources of this variability are not well understood, but evidence suggests that stress can either enhance or inhibit alloparental care. We evaluated immediate and delayed effects of acute stress on pup-directed behavior in adult virgin male California mice. Mice underwent three 10-minute tests with unfamiliar pups at 48-hour intervals. Stressed mice (N=22) received a subcutaneous oil injection immediately before tests 1 and 2, whereas controls (N=22) were left undisturbed. In controls, but not stressed mice, latency to approach the pup decreased and duration of alloparental behavior increased across the three tests. At each time point, stressed males were less likely than controls to perform alloparental behavior. Controls spent significantly more time performing alloparental behavior than stressed mice in tests 1 and 2 but not in test 3. Pup-directed aggression did not differ between the groups at any time point. These findings suggest that acute stress can both inhibit alloparental behavior in the short term and prevent the increase in alloparental behavior that typically occurs with repeated exposure to pups in virgin male California mice.
在许多双亲哺乳动物中，如加利福尼亚鼠（Peromyscus californicus），父亲会对陌生的幼崽表现出亲昵的行为，而没有繁殖经验的成年雄性则表现出高度可变的反应。这种变异性的来源尚不清楚，但有证据表明，压力既可以增强也可以抑制代际照顾。我们评估了急性应激对成年雄性加利福尼亚鼠幼崽行为的即时和延迟影响。雄性老鼠在 48 小时的间隔内接受了三次 10 分钟的陌生幼崽测试。应激组（N=22）在测试 1 和 2 前立即接受皮下油注射，而对照组（N=22）则不受干扰。在对照组中，但不是应激组中，雄性老鼠接近幼崽的潜伏期减少，代际行为的持续时间在三次测试中增加。在每个时间点，应激雄性比对照组更不可能表现出代际行为。对照组在测试 1 和 2 中比应激组花费更多的时间来表现代际行为，但在测试 3 中则不然。在任何时间点，两组的幼崽定向攻击都没有差异。这些发现表明，急性应激既可以在短期内抑制代际行为，又可以防止在没有繁殖经验的加利福尼亚雄性老鼠中，反复接触幼崽时通常会出现的代际行为增加。
