Reproductive Physiology of the Female Blue Crab, Callinectes sapidus: Spawning Induction and Vitellogenesis

Abstract

In aquaculture, spawning is the baseline for production; therefore, the optimization of spawning conditions will directly increase production. The current study aims to optimize spawning conditions for <italic>Callinectes sapidus</italic> using environmental manipulations of photoperiod and temperature for induction while monitoring the physiological vitellogenin (VtG) levels during ovarian development and maturation. The photothermal manipulations for this study resulted in increased spawning events in 21&deg;C temperatures (compared to 11&deg;C and 15&deg;C) and complete darkness (0L:24D; compared to 8L:16D, 16L:8D, and 24L:0D) while 24L:0D and 11&deg;C suppressed spawning. When assessing the VtG levels in the hemolymph prior to, during, and after all spawning events, the VtG showed a decrease prior to spawning, and significant VtG activity was seen in 21&deg;C for all photoperiods. Overall, spawning and vitellogenesis are temperature dependent events with 67% of the females spawning in 21&deg;C. Photoperiod also has an effect on spawning, but not on vitellogenesis.