Developmental time table of the sea urchin Echinometra mathaei found in Talin Bay, Matuod, Lian, Batangas

• Main Authors: Badiola, Ma. Elinore V., Lipana, Bernadette L.
• Format: text
• Language: English
• Published: Animo Repository 1992
• Subjects: Sea urchins—Embryos; Biology
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/3998
• Institution: De La Salle University

This study established the developmental time table of the sea urchin species, Echinometra mathaei, under laboratory conditions of water temperature (25-26 centigrade) and salinity (30-34 ppt.) The sea urchins were allowed to spawn using the chemical induction technique described by Kobayashi (1971). Sea urchin eggs and sperms were mixed and allowed to fertilize and develop in culture beakers filled with aerated, filtered seawater. A small sample was collected every minute for ten minutes, then every ten minutes for two hours, and finally, every hour for forty-eight hours. Samples were fixed using 10 percent formaldehyde. The fixed specimens were examined under the microscope (40x) to determine percent success of attainment of the different stages of development.The study showed that fertilization in E. mathaei is attained 10 to 20 minutes after addition of the sperms to the eggs. The 4-armed pluteal larva stage was the highest developmental stage attained within the 48-hour culture period. E. mathaei attained this stage after 2220-2280 minutes.It was also observed that there is 90-100 percent rate survival of the embryo-larval culture by maintaining salinity at 30-34 ppt and temperature at 25-26 centigrade.