Hatching of embryos in the estuarine crab Sesarma haematocheir is highly synchronized with nocturnal high tide and completes within 1 hr among all embryos incubated by the female. This highly synchronized hatching is induced by a "Hatching-Program Inducing Factor (HPIF)" released from the female. To further define the cues involved in synchronized hatching, experiments were designed to characterize this factor and to determine possible sites of release and temporal release patterns using strategies involving isolation of egg masses, perfusion, and ablation experiments on fully developed embryos that had not yet entered the hatching program. Embryo transplantations indicate that not only HPIF may be released from the branchial chamber, but that it is extraordinarily unstable, and loses activity within 15 min, which frustrates further attempts at characterization. Nevertheless, with regard to temporal release patterns, it was established that HPIF activity was detected during short periods over three consecutive nights prior to release of larvae. This activity did not explain the gated response of embryo release in this crab, which might correspond with circatidal larval release events in the field.
|Number of pages||13|
|Journal||Journal of Experimental Zoology Part A: Comparative Experimental Biology|
|Publication status||Published - Jun 1 2006|
ASJC Scopus subject areas
- Animal Science and Zoology