Reproductive performance of the Pacific red snapper Lutjanus peru supplemented with microalgae ( Grammatophora sp.)

The steady demand for fish in the aquaculture sector has led to the study and implementation of new compounds of natural origin which seek to standardize and maximize production by ensuring reproductive performance. Microalgae have emerged as a renewable source with specific nutritive qualities that allows the enhancement of captive breeding, and the use of local strain aims to facilitate cultivation and reduce production costs. Therefore, in this study, the effect of a diet supplemented with a diatom of the genus Grammatophora obtained from La Paz Bay, Mexico, was evaluated on the reproductive performance of 5-year-old Pacific Red snapper ( Lutjanus peru ). Two isoproteic and isolipidic diets were compared: the control semi-humid diet (R0) and the experimental enriched diet with 3% of Grammatophora sp. silage made by fermentation (R1). Fishes were fed ad libitum 3 months previous to the spawning season during 7 months. Hatching rate was significantly ( P < 0.05) higher for R1 eggs (77%) compared to control (39–64%). For R0, egg sizes fluctuated significantly during the spawning season and presented an average diameter of 782.4 ± 5.5 µm. For R1, the egg diameter, significantly larger (792.5 ± 4.1 µm), was stable throughout the season. Finally, R1 eggs had significant higher polyunsaturated fatty acid content (arachidonic, eicosapentaenoic and docosahexaenoic acids) compared to R0 eggs ( P < 0.05). In conclusion, supplemented mature L. peru with 3% of Grammatophora sp . silage in fish, prior and during spawning season, is recommended to improve their reproductive performance (hatching rate, egg size and egg quality) and ensure larval production.