Abstract

Development, growth and survival were evaluated for larvae of the fighting conch Strombus pugilis under two different photoperiods with three replicates with light phases of O light (0/24 L) and 241ight (24/24 L) per day. Temperature with light phases of O light (0/24 L) and 24light (24/24 L) per day. Temperature culture was 29:1: 1 "C. The veligers were reared at a density of 200 larvae per litre. Larvae were fed Tetraselmis suecica at a concentration of 1,000 cells.ml-l. Proboscis appeared at 17 days in the pholoperiod 24/24 L with 36% while in the larvae 0/24 this characteristic appeared for first time at 19 days with 26%. The veliger were competent for metamorphosis between 26 lo 29 days for photoperiod 24/24 L and between 28 lo 31 days for photoperiod 0/24 L. Photoperiod 24/24 L had a negative effect on survival, lo hatching a settlement, it was significantly lower under 24/24 L with 13% whilst 0/24 L was 44%. Effect of photoperiod was observed too, in the growth, larval growth averaged 22.56 and 29.56 pm/day, respectively.

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