BLERTATurani*,VALBONA ALIKO
Department of Biology, Faculty of Natural Sciences, University of Tirana, Tirana, Albania
*Correspondence author: E-mail: blertaturani@yahoo.com
Abstract
The temperature is a determining factor for the successful development of the larvae in amphibians. The plasticity during metamorphosis is important especially in populations of amphibians living in Mediterranean climate zones with high temperatures and relatively low precipitations, were the risk of pond desiccation is high. To study the effect of water temperature on the embryonal and larval development of in-vitro reproduced Albanian water frog, Pelophylax shqipericus, two batches of approximately 100±20 eggs (stage 14-16, Gosner) were raised in the laboratory at four different temperature regimes (30C, 170C, 200C and 250C), with 12:12 photoperiod. To follow the process of metamorphosis, three important key events were evaluated: budding of the hind limbs (stage 1), the formation of the anterior (stage 2) and posterior limbs (stage 3), and the reduction and disappearance of the tail (stage 4). Development time and stage were strongly affected by temperature variation. The results showed a lengthening of development time with decreasing temperatures and a better survival rate of P. shqipericus with high temperatures. Values of temperature of 190C-200C resulted to be optimal for larval development, while very low temperatures (t=30C) and very high ones (t=250C) strongly impede larval development. These results demonstrate that temperature is one of the most important factors that strongly affects the success of embryonic and larval development of P. shqipericus reproduced in-vitro.Since the Albanian water frog, is a native and an endangered species whose known populations are currently in decline, its successful in-vitro reproduction will contribute to conservation of the specimen.
Keywords: Pelophylax shqipericus, in vitro reproduction, development, temperature.
