The spermatozoa of oviparous fish, such as sea bass, are immotile in the presence of semen plasma or solutions that are isotonic to it, and to obtain good motility, they must be diluted in a suitable medium like sea water. The object of this study was to identify the best protocol for the inactivation and activation of sea bass (Dicentrarchus labrax L.) spermatozoa motility in order to obtain an artificial inactivation of motility, which can be restored when necessary, so that semen can be used not only immediately after collection. Sea bass semen was obtained by abdominal stripping from 50 males in breeding during the reproductive season. The semen, kept at a temperature of 0-2 degreesC, was diluted with the experimental inactivator solutions DI1, DI2 and DI3. The solutions were tested at three ratios of dilution: 1:3, 1:6 and 1:10. The inactivated semen was activated by dilution at a ratio of 1:10 with sea water at pH 7.5 and 8.2. Subsequently, three different inactivated semen/sea water ratios of dilution were tested (1:3, 1:6, 1:10), using sea water at pH 8.2, which proved to have a better activating capacity. In addition, the motility resistance of inactivated, cooled (0-2 degreesC) semen was tested by activation every 12 h to evaluate its duration in time compared to that of undiluted semen. Motility was classified according to the percentage of rapid, vigorous and forward-moving motile spermatozoa (RVF). All tested solutions were good inactivators, as motility was always 0 after dilution. On activation, the best results were obtained with DI2 (dilution ratio 1:6), which restored motility in the highest percentage of spermatozoa; sea water pH 8.2 gave better results than sea water pH 7.5. Although no significant differences were found, a semen/inactivator medium of 1:6 dilution and an inactivated semen/activating solution of 1:10 seem to give the best results. Moreover, chilled (0-2 degreesC) semen diluted in DI, medium preserved its motility longer than undiluted semen stored under the same conditions. (C) 2001 Elsevier Science B.V. All rights reserved.
Inactivator media of sea bass (Dicentrarchus labrax L.) spermatozoa motility
Fabbrocini A;
2001
Abstract
The spermatozoa of oviparous fish, such as sea bass, are immotile in the presence of semen plasma or solutions that are isotonic to it, and to obtain good motility, they must be diluted in a suitable medium like sea water. The object of this study was to identify the best protocol for the inactivation and activation of sea bass (Dicentrarchus labrax L.) spermatozoa motility in order to obtain an artificial inactivation of motility, which can be restored when necessary, so that semen can be used not only immediately after collection. Sea bass semen was obtained by abdominal stripping from 50 males in breeding during the reproductive season. The semen, kept at a temperature of 0-2 degreesC, was diluted with the experimental inactivator solutions DI1, DI2 and DI3. The solutions were tested at three ratios of dilution: 1:3, 1:6 and 1:10. The inactivated semen was activated by dilution at a ratio of 1:10 with sea water at pH 7.5 and 8.2. Subsequently, three different inactivated semen/sea water ratios of dilution were tested (1:3, 1:6, 1:10), using sea water at pH 8.2, which proved to have a better activating capacity. In addition, the motility resistance of inactivated, cooled (0-2 degreesC) semen was tested by activation every 12 h to evaluate its duration in time compared to that of undiluted semen. Motility was classified according to the percentage of rapid, vigorous and forward-moving motile spermatozoa (RVF). All tested solutions were good inactivators, as motility was always 0 after dilution. On activation, the best results were obtained with DI2 (dilution ratio 1:6), which restored motility in the highest percentage of spermatozoa; sea water pH 8.2 gave better results than sea water pH 7.5. Although no significant differences were found, a semen/inactivator medium of 1:6 dilution and an inactivated semen/activating solution of 1:10 seem to give the best results. Moreover, chilled (0-2 degreesC) semen diluted in DI, medium preserved its motility longer than undiluted semen stored under the same conditions. (C) 2001 Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
