Reproductive timing in organisms can influence reproductive success and longevity, yet its long-term effects remain underexplored. This study monitored the first- and last-born offspring of Brachionus plicatilis across five generations to examine the impact of breeding timing on fertility and longevity. The last-born group produced more offspring in the F1 and F2 generations. However, the first-born group produced more offspring from the F3 generation onward, with statistically significant differences observed in the F4 generation. Survival analysis indicated no differences up to the F3 generation. However, the post-reproductive period was significantly shorter in the last group compared to the first group in the F3 and F4 generations. These findings suggest that delayed breeding timing cumulatively reduces reproductive output and lifespan, though recovery may occur in the F5 generation. This study provides valuable insights into the generational effects of breeding timing and may inform reproductive strategies in similar species.

中文翻译：

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海洋轮虫 Brachionus plicatilis 繁殖时间和生命周期参数的多代分析


生物体的繁殖时间会影响繁殖成功和寿命，但其长期影响仍未得到充分探索。这项研究监测了五代 Brachionus plicatilis 的第一个和最后一个出生的后代，以检查繁殖时间对生育能力和寿命的影响。最后一个出生的群体在 F1 和 F2 代中产生了更多的后代。然而，从 F3 代开始，长子组产生了更多的后代，在 F4 代中观察到统计学上的显着差异。生存分析表明，直到 F3 代没有差异。然而，与 F3 和 F4 代的第一组相比，最后一组的繁殖后期明显短。这些发现表明，延迟的繁殖时间会累积减少繁殖输出和寿命，尽管恢复可能会发生在 F5 代。这项研究为育种时间的世代效应提供了有价值的见解，并可能为类似物种的繁殖策略提供信息。