![]() | Effect of sampling location, release technique and time after activation on the movement characteristics of scallop (Pecten maximus) sperm Auteur(s) : Suquet, Marc Quere, Claudie Mingant, Christian Lebrun, Luc Ratiskol, Dominique Miner, Philippe Cosson, Jacky Éditeur(s) : Edp Sciences S A Résumé : Sperm characteristics of scallops have not been well described in the scientific literature. The effects of sperm release technique (thermal shock versus serotonin injection), of sperm collection technique (testis sampling versus serotonin injection), of sperm sampling location along the genital tract, of in vitro sperm maturation, and of time post activation on scallop sperm characteristics were assessed in the present work. Whatever sperm release technique used, no significant differences were observed regarding the percentage of motile spermatozoa and the velocity of the average path (YAP). Compared to testicular sperm, a higher percentage of motile spermatozoa, YAP and intracellular adenosine triphosphate (ATP) content were observed for sperm shed after serotonin injection. From the distal part of testes up to the gonopore, an increase of the percentage of motile spermatozoa and YAP was assessed, suggesting a sperm 'maturation process' along the genital ducts. A higher increase in the percentage of motile sperm was recorded during a 5 mm incubation of testicular sperm in seawater containing 2 mM serotonin and seawater containing 10 mM caffein compared to seawater (control). In addition, a higher YAP was assessed, incubating testicular sperm in caffein, compared to control or serotonin. Then, the percentage of motile spermatozoa, YAP and intracellular ATP content exhibited a progressive reduction during the 10 h swimming period. Mean values of the percentage of motile spermatozoa, YAP, sperm track linearity (LIN) and intracellular ATP content recorded at the beginning of the movement period for sperm samples collected after intragonadal serotonin injection, were 82 +/- 7%, 162 +/- 15 mu m s(-1), 0.33 +/- 0.12 and 212 +/- 133 nmol x 10(-9) spermatozoa (n = 9 males), respectively. The present study confirms the existence of a sperm "maturation process" along scallop genital ducts. In addition, the cessation of scallop sperm movement can be explained by the exhaustion of ATP content at the end of the movement phase. Aquatic Living Resources (0990-7440) (Edp Sciences S A), 2013-07 , Vol. 26 , N. 3 , P. 215-220 Droits : EDP Sciences, IFREMER, IRD 2013 http://archimer.ifremer.fr/doc/00157/26852/24983.pdf DOI:10.1051/alr/2013048 http://archimer.ifremer.fr/doc/00157/26852/ | Partager |
![]() | La production aquacole de coquille Saint-Jacques (Pecten maximus) et le soutien scientifique à l'operation pilote Auteur(s) : Dao, Jean-claude Barret, Jean Carval, Jean-pierre Connan, Jean-paul Corre, Christian Devauchelle, Nicole Fleury, Pierre-gildas Laurent, Pascale Éditeur(s) : 3e Rencontres Scientifiques Internationales du contrat de baie de la rade de Brest. Brest 14-16 mars 1995 Résumé : Aquaculture production of scallop has been identified by a series of technical operations during the past ten years programme under a partnership involving the fishermen organizations with regional and national grants. 3 million juveniles have been produced annually, giving a potential recapture by fishing of 100 to 120 tonnes 3 years later. Results in terms of technical and economical approach have pointed out the principal unknown factors responsable for high costs. 7he pilot programme aims to increase the production to reach a level of 5 million juveniles to support the fishery of the rade de Brest and induce new management of the resources. Two priorities were selected, control of the reproduction in the hatchery to obtain reliable larval and postlarval rearing during a larger period of the year, mainly during summer, and improvement of survival rate of the juveniles by minimizing stress when manipulating the animals. But biological and ecological mechanisms are still poorly understoodfor scallop and generally bibvalves and the last two years have shown unchanged results. The technical pathways shows interactions between the different steps of the production of juveniles where different teams operate separately. Management of the livestock has to be developed to increase the survival rate by better breeding but also to reduce the loss by adapted and coordinated practices. Recapture results indicate that fishery strategies depend also on the production of juvenile, and could orientate the management of the hatchery. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00044/15494/12860.pdf http://archimer.ifremer.fr/doc/00044/15494/ | Partager |
![]() | Etudes sur les mortalitees larvaires de la coquille st Jacques Pecten maximus en ecloserie Auteur(s) : Robert, Rene Miner, Philippe Nicolas, Jean-louis Mazuret, Michel Connan, Jean-paul Résumé : Larval mortalities occurring in molluscan hatcheries have often been associated with bacterial contamination. Although batches of oyster and clam larvae have been routinely reared in the hatchery of Argenton without antibiotics, high larval mortalities have been recorded with Pecten maxirnus under similar conditions. For this species, an addition of chloramphenicol was found necessary. However, this chemical has now been banned in Europe. Thus either substitition products or an improvement in the rearing procedures is essential. Studies carried out have shown that neither a decrease in larval density (1 larvae. ml"l) nor sea water change frequency (1 per day) had any positive effects. Furthermore, elective substances such as sugars were not suitable and the use of another antibiotic, erytromvcine. led to inconsistent results- En ecloserie de mollusques, les mortalités larvaires sont souvent associées à des proliférations bactériennes. Pour les limiter un traitement de l'eau est incontournable et chez certaines espèces, dont la coquille St Jacques Pecten maximus, l'utilisation de chloramphenicol s'avère nécessaire. Or son usage dans les productions animales a été récemment prohibé par la communauté européenne. Afin de pallier à cette interdiction, l'amélioration des procédures zootechniques ainsi que l'utilisation de produits de substitution ont été effectuées. Quel que soit le procédé envisagé, abaissement de la densité en élevage, augmentation de la fréquence du renouvellement de l'eau d'élevage, mise au point de filtres biologiques, utilisation de substances électives, les élevages larvaires n'ont pu être menés à terme. A l'inverse, de bons développement larvaires ont été obtenus avec adjonction d'érythromycine mais ces résultats ne sont pas suffisamment reproductibles pour que cet antibiotique constitue un produit de substitution efficace. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/1995/rapport-1568.pdf http://archimer.ifremer.fr/doc/00000/1568/ | Partager Voir aussi Mortality Pecten maximus Hatchery Larvae Mollusc Mortalité Pecten maximus Ecloserie Larve Mollusque Télécharger |
![]() | Observations on larval development and settlement of Patinofecten yessoensis in hatcheries Auteur(s) : Robert, Rene Miner, Philippe Mazuret, Michel Connan, Jean-paul Éditeur(s) : Proceedings of the 9th International Pectinid Workshop, Canada Résumé : The influence of density on Patinopecten yessoensis larval development was studied during production of an F2 generation. Setting behaviour of P. yessoensis on PVC removable spat collectors, previously tested with Pecten maximus, was determined. Poor larval growth of P. yessoensis was observed at a larval density of 7 ·ml·1 and post larval settlement occurred mainly on the bottom of the baskets, as has been observed with the king scallop, P. maximus. The PVC collector is not suitable for either species of scallop. Droits : 1994 Ifremer http://archimer.ifremer.fr/doc/00090/20163/17816.pdf http://archimer.ifremer.fr/doc/00090/20163/ | Partager |