Photoperiod in the sea urchin aquaculture of Arbacia dufresnii (Echinodermata: Echinidea): Its efects on gametes production and maturity

SEPÚLVEDA, LUCAS ROBERTO; FERNANDEZ, JIMENA PÍA; MERCEDES VERA PIOMBO; CHAAR, FLORENCIA; RUBILAR PANASIUK, CYNTHIA TAMARA

REVISTA DE BIOLOGÃA TROPICAL

REVISTA DE BIOLOGÃA TROPICAL

Lugar: Turrialba; Año: 2020

Photoperiod in the sea urchin aquaculture of Arbacia dufresnii (Echinodermata: Echinoidea): Its effect on gamete production and maturityIntroduction: Photoperiods are, together with temperature and food availability, one of the main stimulus in the development of gametogenesis in a wide variety of species. Objetive: The objetive of this study was to evaluate the effect of the photoperiod on the production of mature gametes in Arbacia dufresnii in a closed recirculating aquaculture system (RAS) to determine the optimum photoperiod to achieve a novel aquaculture focus in producing gametes with a high concentration of pigments, to be used for biotechnological purposes. Methods: An experiment was carried out with three different light-dark regimes. The treatments consisted of constant light (24 h light), neutral photoperiod (12L:12D) and constant darkness (24 h darkness). Twenty females were used in each treatment. All females were induced to spawn at the beginning of the experiment. After 30 days, ten randomly selected females from each treatment were induced to spawn. At the end of the experiment, after 60 days, spawning was induced in the remaining females in each treatment. The gametes were collected in filtered seawater, fixed in a Davidson solution, quantified and measured per individual in triplicate in a Sedgewick-Rafter chamber. To determine maturation, fertilization success was evaluated after 30 minutes of fertilization. The percentage of fertiliszed eggs was calculated. Results: Our results showed that in the aquaculture system, in only two month mature gametes were obtain and in 12L:12D light regime there were 10 times more amount of gametes that the produced by wild sea urchins at the spawning period. We also found that with the greater exposure to light, a lower number of mature gametes was produced. Conclusions: This study suggests the viability of the production of mature gametes in a short period of time in Arbacia dufresnii.