జర్నల్ ఆఫ్ ఆక్వాకల్చర్ రీసెర్చ్ & డెవలప్‌మెంట్

నైరూప్య

Effect of Temperatures on the Embryonic Development, Morphometrics and Survival of Macrobrachium Idella Idella (Hilgendorf, 1898)

Soundarapandian P, Dinakaran GK and Varadharajan D

The development of M. idella idella eggs incubated at four different temperatures (26, 30, 33 and 36°C). An increase in major axis length was evident at 26, 30, 33 and 36°C. However at 36°C, size variation increased with developmental stages, indicating abnormalities until 192 h, after which total mortality was observed. A distinct change in morphometric parameters (major half axis, minor half axis, area and perimeter) was demonstrated at higher temperatures, irrespective of the developmental duration of eggs. Length of hatched embryos increased with increasing incubation temperatures. Therefore a rapid rate of increase of major half axis and early hatching was observed at 33°C. The larva hatched first in 33°C (241 hrs) then followed by 30°C (265 hrs) and 26°C (302 hrs). In 36°C (182 h) there was total mortality during embryonic development so there was no hatching.