Advances in rearing techniques ofPagrus pagrus,(Linnaeus, 1758): comparison between intensive and semi-intensive larval rearing systems

Red porgy, Pagrus pagrus L., is a potential candidate for marine finfish diversification on commercial Mediterranean and Atlantic coastal aquaculture. This paper described the development of a suitable larval rearing protocol for commercial application. Red porgy eggs were reared under Intensive and Semi-intensive systems until 50 days after hatching. In addition, two different weaning protocols were tested for each rearing system. The effects of these treatments were evaluated on the growth, survival and whole-body biochemical and fatty acid composition of red porgy larvae. Significant differences in growth but not in survival at 50 days after hatching were detected in trial A for the semi-intensive and intensive rearing system (23.5 ± 2.7-18.9 ± 3.4 mm; 4.4-4.9%); however, modifications in initial prey density and illumination conditions, implemented in trials B (29.5 ± 3.0-25.2 ± 1.9 mm; 21.8-5.3%) and C (26.2 ± 2.6-24.6 ± 2.6 mm; 22.7-3.8%), significantly improved survival and growth rates in the semi-intensive rearing system. Furthermore, the results in trial C confirmed the feasibility of a partial reduction in Artemia use and the significant improvement in survival rates with the new weaning protocol applied (26.4 ± 2.3-24.1 ± 3.9 mm; 28.7-12.5%) in the intensive systems. The results of this study concluded that the best larval rearing protocol for commercial production of red porgy fingerlings should include the use of semi-intensive systems.