ABSTRACT

The photoperiod regulates the growth and development of many animals. We conducted experiments and studied the effect of the photoperiod on the growth and development of the larvae and young of two amphibian species Rana temporaria and Xenopus laevis. We studied photoperiods: constant absence of light – 0 h light/24 h darkness (0L/24D), 8 h light/16 h darkness (8L/16D), 12 h light/12 h darkness (12L/12D), 16 h light/8 h dark (16L/8D), and round-the-clock lighting (24L/0D). We found out that the size of the Rana temporaria tadpoles was the highest with photoperiods 24L/0D, 16L/8D, 12L/12D. A decrease in the parameters was observed in the absence of light and the photoperiod 8L/16D. The pace of development began to differ after the 10th day of the experiment. The development was slower with the photoperiod 0L/24D. The highest percentage of tadpoles’ mortality was observed in total darkness (0L/24D), the lowest percentage was observed in the photoperiod 16L/8D. The photoperiod had no effect on the Xenopus laevis young. The mechanisms of the photoperiod’s effect on the larval development and growth of amphibians are discussed.

摘要

光周期调节许多动物的生长和发育。我们进行了实验，研究了光周期对两种两栖动物林蛙和非洲爪蟾幼虫生长发育的影响。我们研究了光周期：持续缺光 – 0 小时光照/24 小时黑暗 (0L/24D)、8 小时光照/16 小时黑暗 (8L/16D)、12 小时光照/12 小时黑暗 (12L/12D)、16 小时亮/8 小时暗 (16L/8D) 和全天候照明 (24L/0D)。我们发现林蛙的大小蝌蚪最高，光周期为24L/0D、16L/8D、12L/12D。在没有光和光周期为 8L/16D 的情况下观察到参数下降。实验的第 10 天后，发展的速度开始不同。光周期为0L/24D时显影较慢。在完全黑暗 (0L/24D) 中观察到的蝌蚪死亡率百分比最高，在光周期 16L/8D 中观察到的百分比最低。光周期对年轻的非洲爪蟾没有影响。讨论了光周期对两栖动物幼虫发育和生长的影响机制。