Artificial maturation and larval production of the limpet Patella aspera Roding, 1798 (Patellogastropoda, Mollusca): Enhancing fertilization success of oocytes using NaOH-alkalinized seawater

摘要

Patella aspera is a valuable limpet species native from the Macaronesian Region, which commercial exploitation is regulated due to overfishing. Aquaculture production of the species has the potential to be a sustainable alternative to the exploitation of this natural resource. This is the first study of the larval production of P. aspera with oocytes obtained from dissected gonads and artificially matured using NaOH-alkalinized seawater. An artificial maturation experiment obtained the higher ratio of matured oocytes employing alkalinized seawater at pH 9.0 and 9.5 from 3 to 5 h. In vitro experiments combined similar artificial maturation conditions: pH 9 and 9.5 (plus pH 8 as control) during 1:30, 3:00 and 4:00 h; with three fertilization times (1:30, 3:00 and 24:00 h) to determine the combination of factors leading to higher larval production. Results show increased larval production, ranging from 50% to 75% total fertilized oocytes, using alkalinized baths at pH 9 from 3 to 4 h, followed by 24 h fertilization time at 19 +/- 1 degrees C. The present methodology ensures the production of P. aspera larvae, a mandatory step for further studies focused on the larviculture and aquaculture production of this limpet species.