FN Archimer Export Format
PT J
TI Gametogenetic cycle and reproductive effort assessed by two methods in 3 age classes of Pacific oysters, Crassostrea gigas, reared in Normandy
BT 
AF ROYER, J
   SEGUINEAU, Catherine
   PARK, K
   POUVREAU, Stephane
   CHOI, K
   COSTIL, K
AS 1:1;2:2;3:3;4:4;5:5;6:1;
FF 1:;2:;3:;4:PDG-DOP-DCB-PFOM-PI;5:;6:;
C1 Univ Caen Basse Normandie, Lab Biol & Biotechnol Marine, IFREMER, IFR ICORE,UMR 100, F-14032 Caen, France.
   Univ Bretagne Occidentale, IFREMER, Lab Physiol Invertebres, UMR 100, F-29280 Plouzane, France.
   Kunsan Natl Univ, Dept Aquat Life Med, Kunsan 573701, Chonbuk, South Korea.
   IFREMER, Unite Expt Argenton, Lab Physiol Invertebres Marines, UMR 100, F-29840 Landunvez, France.
   Cheju Natl Univ, Sch Appl Marine Sci, Cheju 690756, South Korea.
C2 UNIV CAEN, FRANCE
   UBO, FRANCE
   UNIV KUNSAN NATL, SOUTH KOREA
   IFREMER, FRANCE
   UNIV CHEJU NATL, SOUTH KOREA
SI BREST
   ARGENTON
SE PDG-DOP-DCB-PFOM-PI
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-univ-france
   copubli-int-hors-europe
IF 1.678
TC 53
UR https://archimer.ifremer.fr/doc/2008/publication-4305.pdf
LA English
DT Article
DE ;Reproductive effort;Image analysis;Gametogenetic cycle;ELISA;Crassostrea gigas;Condition index
AB Two methods were used to estimate the reproductive output of female Pacific oysters reared in Normandy: histology with image analysis and ELISA (Enzyme-Linked lmmunoSorbent Assay) which allowed the quantification of egg protein. Condition indices, gonad area and gametogenetic stages of the oysters were determined in the entire population (males and females) between May and October 2005. All investigations were performed in 3 age classes: oysters in their first, second or third years (corresponding to spat, half-grown and market-sized oysters, respectively). Both quantitative histology and ELISA provided similar results in terms of reproductive effort (illustrated by the gonado-somatic index, GSI) except during the GSI drop, corresponding to spawning, which was less marked with the ELISA method. Growth depended on oyster age, the sex ratio was well balanced and the reproductive cycle was synchronized in all age classes. In the 3 age classes, most of the oysters were ripe and ready to spawn on August 8, and ten days after the post-spawning stage was observed in 40% of spat oysters and 70% of half-grown and market-sized bivalves. The major difference between age classes was observed in the reproductive investment, with spat having a lower reproductive output. For example, in males and females, the gonad area reached 78-79% in the median animal section at full maturity (August 8) in half-grown and marketable oysters while it attained only 59% in spat. At the same time, GSI in females was, respectively in spat and the 2 oldest age classes, 33% (quantitative histology)-36% (ELISA) and 55% (quantitative histology)-60% (ELISA). The mean assessed gonad weight and fecundities increased with the age of the oysters: 1.3 g and 12 million eggs, 7.8 g and 135 million eggs, and 11.5 g and 146 million eggs in spat, half-grown and market-sized oysters, respectively. Marked differences thus appear between 2 and 3-year-old oysters and spat. As early as their first reproductive cycle, the young oysters not only showed the reproductive features of the species in Normandy, but also a pronounced lower reproductive effort. This lower energy demand could explain their higher survival rate. (C) 2008 Elsevier B.V. All rights reserved.
PY 2008
PD JUL
SO Aquaculture
SN 0044-8486
PU Elsevier
VL 277
IS 3-4
UT 000256275700026
BP 313
EP 320
DI 10.1016/j.aquaculture.2008.02.033
ID 4305
ER

EF