Menoud M., Van Wynsberge S., Le Moullac G., Levy P., Andréfouët Serge, Remoissenet G., Gaertner-Mazouni Nabila. (2016). Identifying robust proxies of gonad maturation for the protandrous hermaphrodite Tridacna maxima (Roding, 1798, Bivalvia) from individual to population scale. Journal of Shellfish Research, 35 (1), p. 51-61. ISSN 0730-8000.
Titre du document
Identifying robust proxies of gonad maturation for the protandrous hermaphrodite Tridacna maxima (Roding, 1798, Bivalvia) from individual to population scale
Année de publication
2016
Auteurs
Menoud M., Van Wynsberge S., Le Moullac G., Levy P., Andréfouët Serge, Remoissenet G., Gaertner-Mazouni Nabila
Source
Journal of Shellfish Research, 2016,
35 (1), p. 51-61 ISSN 0730-8000
Monitoring gonad maturation for protandrous and functional hermaphrodite species such as the giant clam Tridacna maxima is difficult due to the juxtaposition and relative proportion of male and female tissues in the gonad [gonadal sex ratio (GSR)]. Here, the relevance of the widely used gonadosomatic index (GSI) as proxy of giant clam gonad maturation is tested with a large dataset (n = 265). Gonadosomatic index is compared with other indices, namely the proportion of the male part harboring spermatozoids, the proportion of empty oocyte follicles, the mean oocyte diameter, and the oocyte elongation. At gonad scale, high index variability highlighted partial spawning. At individual scale, male and female maturation proxies were contrasted, showing either asynchronous emissions of male and female gametes or contrasted spermatogenesis and oogenesis duration. The GSI was mostly driven by the number and diameter of oocytes and therefore it is recommended here as primary proxy for female maturity. Except for the oocyte elongation, all indices were affected by the GSR, which ruled out drawing conclusions at population scale. These results highlight the need for maturation stage proxies that are optimized for functional hermaphrodite species.
Plan de classement
Limnologie biologique / Océanographie biologique [034]
Description Géographique
POLYNESIE FRANCAISE ; TUAMOTU GAMBIER
Localisation
Fonds IRD [F B010066967]
Identifiant IRD
fdi:010066967
