Astudillo David, Rosas Jesús, Velásquez Aidé, Cabrera Tomas, Maneiro Carlos
Escuela de Ciencias Aplicadas del Mar, Universidad de Oriente Núicleo de Nueva Esparta, Boca del Rio, Estado Nueva Esparta, Venezuela.
Rev Biol Trop. 2005 Dec;53 Suppl 3:337-44.
Thirty sexually mature sea urchins (Echinometra lucunter; diameter 45.8 +/- 17.5 mm) were collected at Macanao, Margarita Island, Venezuela (11 degrees 48'29" N / 64 degrees 13'10" W). They were injected potassium chloride (50 M) directly into the celomic cavity. After two minutes 90% spawned (17 females and 10 males), the others never spawned. Fertilization was 87.0 +/- 12.6% (1:100 oocytes/sperm) at 29 +/- 2 degrees C. The fertile eggs were placed in three treatment gropsu with nine containers (18 liters; 2 eggs/ml) each, all with bottom aeration. Treatments were: Chaetoceros gracilis; Isochrysis galbana, and a mixture of both microalgae (respectively: 20 000 and 60,000 cell/ml for each microalgae, 1:1 for the mixture). Salinity, pH, temperature and larval survival were determinated daily. The study ended when the post-metamorphic phase was completed. The embryonic development time was 16.3 +/- 0.2 h until the prism stage at pH 8.4 +/- 0.1; 38 +/- 1 psu and 28 +/- 1.4 degrees C. The two-arms larval stage was reached at 24 h: 33 min, with a total length of 190 +/- 16.3 microm fed on C. gracilis, 152 +/- 19.0 microm with I. galbana and 182.4 +/- 14.1 microm with the mixture. The larvae next to metamorphosis reabsorbed the arms and had the characteristic shape of juvenile urchins at 12 days with 670.2 +/- 22.2 microm fed on C. gracilis, 665 +/- 12.1 microm fed on I. galbana and 670 +/- 14.1 microm fed on the mixture. The accumulated survival to the juvenile stage was 14.7 +/- 3.8% when fed on C. gracilis, higher than the other treatments (5.4 +/- 1.2; 14.0 +/- 2.6). E. lucunter is an excellent prospect to be commercially cultured because of its short embryonic (16 hours) and larval development time (12 days) and good survival rate when fed on monoculture (C. gracilis and I. galbana) or mixed diet (we recommend C. gracilis).
30只性成熟的海胆（Echinometra lucunter；直径45.8±17.5毫米）在委内瑞拉玛格丽塔岛的马卡瑙采集（北纬11度48分29秒/西经64度13分10秒）。将氯化钾（50M）直接注入它们的体腔。两分钟后，90%的海胆产卵（17只雌性和10只雄性），其他的则从未产卵。在29±2摄氏度下，受精率为87.0±12.6%（卵母细胞/精子比例为1:100）。将可育卵放入三个处理组，每组九个容器（18升；每毫升2个卵），均有底部曝气。处理方式为：纤细角毛藻；等鞭金藻，以及两种微藻的混合物（每种微藻分别为20000和60000个细胞/毫升，混合物比例为1:1）。每天测定盐度、pH值、温度和幼体存活率。当变态后阶段完成时，研究结束。在pH值8.4±0.1、盐度38±1 psu和温度28±1.4摄氏度的条件下，直到棱柱期的胚胎发育时间为16.3±0.2小时。在24小时33分钟时达到双臂幼体阶段，以纤细角毛藻为食时总长度为190±16.3微米，以等鞭金藻为食时为152±19.0微米，以混合物为食时为182.4±14.1微米。接近变态的幼体吸收了臂部，在12天时具有幼海胆的特征形状，以纤细角毛藻为食时为670.2±22.2微米，以等鞭金藻为食时为665±12.1微米，以混合物为食时为670±14.1微米。以纤细角毛藻为食时，幼体阶段的累积存活率为14.7±3.8%，高于其他处理组（5.4±1.2；14.0±2.6）。由于其胚胎发育时间短（16小时）和幼体发育时间短（12天），并且在以单一培养（纤细角毛藻和等鞭金藻）或混合饲料（我们推荐纤细角毛藻）为食时具有良好的存活率，Echinometra lucunter是商业养殖的一个极佳选择。
