Cryopreservation of sea bass (Dicentrarchus labrax) spermatozoa in experimental and production simulating conditions
A sperm cryopreservation protocol adapted from turbot, was tested on sea bass using either 250-mu L straws or 1.5-mL cryovials. A dilution to 1/3 in Mounib's extender and a cooling rate of 65 degrees C.min(-1) allowed frozen sperm to recover an initial motility similar to that of fresh sperm at...
| Published in: | Aquatic Living Resources |
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| Main Authors: | , , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Elsevier
1998
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| Subjects: | |
| Online Access: | https://archimer.ifremer.fr/doc/00000/866/528.pdf https://doi.org/10.1016/S0990-7440(99)80004-7 https://archimer.ifremer.fr/doc/00000/866/ |
| Summary: | A sperm cryopreservation protocol adapted from turbot, was tested on sea bass using either 250-mu L straws or 1.5-mL cryovials. A dilution to 1/3 in Mounib's extender and a cooling rate of 65 degrees C.min(-1) allowed frozen sperm to recover an initial motility similar to that of fresh sperm at thawing; however, significant differences in motility (P < 0.001, n = 10 fish semen) were observed at further post-activation times, the motility decrease being faster in thawed sperm. At the experimental scale, triplicate inseminations of 2-mL aliquots (approximately 2 000 eggs) showed a significant fertility decay of thawed sperm compared to that of fresh sperm (P < 0.01, n = 12 fish semen) when a discriminating 35.10(3) spermatozoa to egg ratio was applied. When 70.10(3) and 200.10(3) spermatozoa per egg were provided in the same experimental conditions, no significant difference appeared between the fertilisation rates of fresh arid thawed sperm. In order to validate the procedure for production or cryobank purpose, a scaled-up protocol was established. Two and 50 mL batches of eggs (approximately 2.10(3) and 50.10(3) eggs, respectively) were inseminated in triplicate using either fresh or-thawed individual sperms of 5 males with 200.10(3) spermatozoa per egg. The mean fertility decreased by 23.5% due to cryopreservation. This decline was explained by the loss of fertility of only one sperm, and only in large-volume conditions, probably due to the delay of use after thawing. Un protocole de cryoconservation du sperme mis au point chez le turbot a été appliqué au loup en petit (250 μL) et grand volume (1,5 mL). Dilué dans le milieu de Mounib et congelé par une baisse de température de −65 °C·min−1, le sperme a présenté à la décongélation une motilité initiale comparable à celle du témoin, mais une chute de motilité significativement supérieure (p< 0,001, n= 10) aux temps d'observation ultérieurs. L'insémination de petits volumes (2mL, soient approximativement 2 000 ovules) à l'aide d'un nombre limitant de 35 ... |
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