Effect of rearing technique over skeletal deformities incidence and osteological development in red porgy Pagrus pagrus (Linnaeus, 1758) larvae

[EN]Red porgy is a candidate species for marine aquaculture diversification.The objective of the present study was to describe the osteological development and the occurrence of skeletal deformities in Pagrus pagrus larvae in relation to the intensification of the rearing system. Fish samples were periodically collected along the development from hatching to juveniles (95days after hatching). Osteological development and the presence of skeleton abnormalities were evaluated. X-ray studies revealed a high number of fish (Semi-intensive:38.8%; Intensive:46.5 %) with skeletal deformities. No significant interaction was found on the incidence of lordosis and fused vertebrae with the rearing tecnique. However, cranial abnormalities and kyphosis incidences were significantly higher in intensive system cultured red porgy. Also, the position of fused vertebrae in this fish was located mainly in the caudal area instead of pre-hemal area for semi-intensive system reared red porgy. Present results, suggest a relationship among feeding sequence, osteological development and deformity incidence and location in red porgy larvae

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.