Résumé: The sperm of seabass is very fragile and it quickly loses its ability to fertilize after collection either if kept undiluted or in classic saline media. In order to avoid cryopreservation when only short conservation is required, the process of sperm management including sperm collection, sperm dilution rate in storage medium and storage medium composition, was subject to experimental trials. A concentration of 20% urine generated a low pH of seminal fluid, and it immediately altered the motility ability. However, pH did not seem to be the key agent of motility prevention since sperm dilution in Leibovitz culture medium (L15) or in classic saline medium both presenting a similar low pH (7.3) did not affect motility. L15 increased the duration of sperm survival by 2 days at 4 degrees C after collection. Moreover, dilution could be restricted to 1 : 3 (v : v) for conservation of chilled sperm. Chilled sperm could be cryopreserved with no more damages than those observed after freezing of fresh sperm.