Embryonic and larval development of haliotis tuberculata coccinea reeve: an indexed micro-photographic sequence

[EN] First description of the complete embryo and larval development of the Canarian abalone (Haliotis tuberculata coccinea Reeve.) was conducted along 39 stages from fertilization to the appearance of the third tubule on the cephalic tentacles and illustrated in a microphotographic sequence. Eggs obtained by induced spawning with hydrogen peroxide from the GIA captive broodstock were stocked at a density of 10 eggs/mL and kept at 23 0.5 BC for 62 h until the formation of the third tubule. Live eggs and larvae were continuously observed on a 24 h basis at a 3400 magnification under transmitted light. At each stages, specific morphological features, illustrated by microscopic photographs, were described, as well as the time required for their apparition. Fertilized eggs diameter was 205 8 mm (mean SD), whereas length and width of larvae ready to undergo metamorphosis were 216.6 5.3 mmand 172 8.8 mm, respectively. Knowledge on the larval morphological development acquired through this study will contribute to the improvement of larval rearing techniques for this abalone species.

Morphological, histological, histochemical and behavioral aspects during early development of red porgy Pagrus pagrus L. reared in mesocosm.

[EN]The present study provides a description of the morphological, histological and histochemical development, and the ecological implications of red porgy larvae reared in mesocosm, from hatching to 30 days after hatching (DAH).

Effect of rearing techniques over, survival growth and skeletal abnormalities development in red porgy (Pagrus Pagrus) larvae

[EN] Red porgy is one of the most interested new species for Spanish and other Mediterranean countries. Although no industrial procedures for fry production has been yet developed. The aim of this work was to develop an industrial scale larval rearing protocols testing the viability of two different rearing techniques (semi-intensive vs intensive) in pilot scale facilities. The second objective was to obtain information about the contribution of rearing system to the apparition of morphological abnormalities such as lordosis, opercular deformities and upper/lower jaws shortening which are considered as quality descriptors in commercial marine fish fry production and seem to be related with larval culture conditions in early larval stages. For that purpose, two different larval rearing systems semi-intensive and intensive were compared using the same live feed enrichments. Biochemical composition of larvae, preys and commercial products was analysed. At 50 days post hatching six hundred fish per treatment was individually studied under stereoscope and abnormalities frequency recorded. At 95 days post hatching fry were soft X ray monitored as well. Survival and abnormalities frequency were similar between treatments although a better growth in terms of total length was obtained in the semi-intensive system.