Sex determination by ultrasonography prior to artificial breeding of the pufferfish Arothron manilensis (Tetraodontiformes, Tetraodontidae).

Artificial breeding was induced in the pufferfish Arothron manilensis following ultrasonographic sex determination. Hormonal treatment of mature male and female specimens followed the collection (and measurement) of fully developed eggs by cannulation. Fertilized eggs (0.85 ± 0.02 mm diameter) were spherical, demersal and individually adhesive. Hatching occurred 5 days after fertilization, larvae being 2.23 ± 0.15 mm in total length and 2.08 ± 0.14 mm in notochord length. The larvae had all died within 14 days of hatching. To improve artificial breeding techniques for A. manilensis, it is necessary to determine more appropriate timing for hormone injection, as well as feeding nutrient-enhanced SS type Brachionus sp. to newly hatched larvae.