The effect of the photoperiod on the larval development and growth of two amphibian species (Amphibia: anura)

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.

KEYWORDS:

• Photoperiod
• growth
• development
• tadpoles
• amphibia
• Rana temporaria
• Xenopus laevis

Disclosure statement

No potential conflict of interest was reported by the author.