Effect of photoperiod on the embryonic development of obscure puffer (takifugu obscurus)

Abstract

The effect of photoperiod on development and hatchmg success of the obscure puffer (Takifugn obscurus) was studied by determining total hatch, total mortality, viability of newly hatched larvae 24 h post-hatch, and time to 50% hatch for embryos incubated at four photoperiod regimes: 24L:0D, 12L: 12D, 0L:24D, and natural photoperiod. The results indicated that total hatch, total mortality, and viability of newly hatched larvae were not significantly different among photoperiod treatments (P>0.05). However, time to 50% hatch decreased with increasing length of photoperiod. Hatching time for embryos incubated under continuous light was significantly shorter than the other three treatments (P < 0.05). © 2004, Copyright Taylor & Francis Group, LLC.