EFFECT OF THE AGING PROCESS ON THE QUALITY OF SEA BASS (DICENTRARCHUS LABRAX) SEMEN

C. Dreanno, M. Suquet, C. Fauvel, J.R. Le Coz, G. Dorange, L. Quemener, R. Billard-1999

Journal of Applied Ichthyology, 15 (6): 176-180 (from Current Contents)

Abstract:

At the end of the female spawning period, an aging phenomenon affects sea bass spermatozoa. Compared with 24 days after the beginning of the female spawning season, a significant decrease of spermatozoa concentration was assessed 14 days after the end of this period (from 2.88 +/- 0.08 to 2.44 +/- 0.11 x 10(10) spermatozoa/mL). Morphological studies revealed a detachment of the plasma membrane in the apical part of the cell. A cytoplasmic space containing vacuoles appeared. A lower ATP content and adenylate energy charge were also recorded (respectively: 86.5 +/- 4.5 versus 63.9 +/- 1.3 nmol/10(9) spermatozoa and 90.2 +/- 1.2 versus 84.7 +/- 1.3%). Towards the end of the reproductive period a lower motility index was determined at 30 s post-activation (2.7 +/- 0.2 versus 0.8 +/- 0.2). Furthermore, the fertilizing capacity of sperm samples collected at the beginning of the milting season (49.9 +/- 2.6%) was significantly higher than that assessed at the end of this period (31.5 +/- 0.9%) and the short-term storage and freezing capacities were also altered. The existence of sperm senescence in sea bass is discussed in relation with the discontinuous spermatogenesis suggested in this fish species.

(IFREMER, Lab Poissons, BP-70, F-29280 Plouzane, France, e-mail of M. Suquet : marc.suquet@ifremer.fr)

home

------------------------------------------------------------------------------