Ontogeny of the feeding apparatus of hatchery-reared white margined sole, Dagetichthys marginatus (Soleidae): implications for cultivation

摘要

P>The aim of this study was to describe the ontogeny of the feeding apparatus of hatchery-reared Dagetichthys marginatus and to discuss development in relation to generalized early development in (flat)fish and the potential influence of reproduction and/or rearing practices used. Fertilized eggs were obtained from hormone-induced wild females of the white margined sole, D. marginatus. Subsequent larvae were reared until shortly after metamorphosis between 35 and 45 dah (days-after-hatching) when mortalities occurred. At 4 dah a small maxilla and two paired branchial arches appeared. Metamorphosis was completed at 22 dah while the left/migrating eye still remained in its initial position at 31 dah. Based on the likely disadvantages for survival it is assumed that the observed development indicates underdevelopment rather than an evolutionary adaptation. The influence of reproduction and rearing practices used on development and mortalities are discussed.