Abstract
Gonad and blood samples were taken from the captive female Japanese sardine Sardinops melanostictus between 1988 and 1989, and changes in serum levels of gonadal steroids were correlated with the annual gonadal cycle. Under captive conditions, female fish did not mature and spawn spontaneously, although oocytes developed up to the end of vitellogenic growth. Based on evidence from ovarian histology, the annual gonadal cycle of the Japanese sardine was divisible into four periods, i.e., immature (June to October), vitellogenesis (November to December), spawning (January to March), and post-spawning (April to May). The pattern of seasonal change in the gonadosomatic index (GSI) showed an inverse correlation to change in water temperature and reflected the degree of ovarian maturity. The serum estradiol-17 β level increased from its lowest concentration (0.12 ng ml-1) in September to a peak (1.14 ng ml-1) in March. Serum 17 α,20 β-dihydroxy-4-pregnen-3-one (17 α,20 β-P) was detectable at low levels (<0.3 ng ml-1) between October and February, but was below the assay detection limit (0.06 ng ml-1) at all other times. Testosterone was not detectable (<0.06 ng ml-1) in the serum of any fish throughout the year. The effects of several steroids on the maturation of follicle-enclosed oocytes of sardine were examined in vitro, and 17 α,20 β-P was found to be the most potent inducer of maturation. This suggests that post-vitellogenic oocytes of the Japanese sardine in captivity have an ability to respond to an appropriate hormonal effector and subsequently to resume meiotic maturation.
| Original language | English |
|---|---|
| Pages (from-to) | 21-29 |
| Number of pages | 9 |
| Journal | Marine Biology |
| Volume | 108 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - Feb 1 1991 |
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All Science Journal Classification (ASJC) codes
- Ecology, Evolution, Behavior and Systematics
- Aquatic Science
- Ecology
Cite this
Annual reproductive cycle of the captive female Japanese sardine Sardinops melanostictus : Relationship to ovarian development and serum levels of gonadal steroid hormones. / Matsuyama, M.; Adachi, S.; Nagahama, Y.; Kitajima, C.; Matsuura, S.
In: Marine Biology, Vol. 108, No. 1, 01.02.1991, p. 21-29.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Annual reproductive cycle of the captive female Japanese sardine Sardinops melanostictus
T2 - Relationship to ovarian development and serum levels of gonadal steroid hormones
AU - Matsuyama, M.
AU - Adachi, S.
AU - Nagahama, Y.
AU - Kitajima, C.
AU - Matsuura, S.
PY - 1991/2/1
Y1 - 1991/2/1
N2 - Gonad and blood samples were taken from the captive female Japanese sardine Sardinops melanostictus between 1988 and 1989, and changes in serum levels of gonadal steroids were correlated with the annual gonadal cycle. Under captive conditions, female fish did not mature and spawn spontaneously, although oocytes developed up to the end of vitellogenic growth. Based on evidence from ovarian histology, the annual gonadal cycle of the Japanese sardine was divisible into four periods, i.e., immature (June to October), vitellogenesis (November to December), spawning (January to March), and post-spawning (April to May). The pattern of seasonal change in the gonadosomatic index (GSI) showed an inverse correlation to change in water temperature and reflected the degree of ovarian maturity. The serum estradiol-17 β level increased from its lowest concentration (0.12 ng ml-1) in September to a peak (1.14 ng ml-1) in March. Serum 17 α,20 β-dihydroxy-4-pregnen-3-one (17 α,20 β-P) was detectable at low levels (<0.3 ng ml-1) between October and February, but was below the assay detection limit (0.06 ng ml-1) at all other times. Testosterone was not detectable (<0.06 ng ml-1) in the serum of any fish throughout the year. The effects of several steroids on the maturation of follicle-enclosed oocytes of sardine were examined in vitro, and 17 α,20 β-P was found to be the most potent inducer of maturation. This suggests that post-vitellogenic oocytes of the Japanese sardine in captivity have an ability to respond to an appropriate hormonal effector and subsequently to resume meiotic maturation.
AB - Gonad and blood samples were taken from the captive female Japanese sardine Sardinops melanostictus between 1988 and 1989, and changes in serum levels of gonadal steroids were correlated with the annual gonadal cycle. Under captive conditions, female fish did not mature and spawn spontaneously, although oocytes developed up to the end of vitellogenic growth. Based on evidence from ovarian histology, the annual gonadal cycle of the Japanese sardine was divisible into four periods, i.e., immature (June to October), vitellogenesis (November to December), spawning (January to March), and post-spawning (April to May). The pattern of seasonal change in the gonadosomatic index (GSI) showed an inverse correlation to change in water temperature and reflected the degree of ovarian maturity. The serum estradiol-17 β level increased from its lowest concentration (0.12 ng ml-1) in September to a peak (1.14 ng ml-1) in March. Serum 17 α,20 β-dihydroxy-4-pregnen-3-one (17 α,20 β-P) was detectable at low levels (<0.3 ng ml-1) between October and February, but was below the assay detection limit (0.06 ng ml-1) at all other times. Testosterone was not detectable (<0.06 ng ml-1) in the serum of any fish throughout the year. The effects of several steroids on the maturation of follicle-enclosed oocytes of sardine were examined in vitro, and 17 α,20 β-P was found to be the most potent inducer of maturation. This suggests that post-vitellogenic oocytes of the Japanese sardine in captivity have an ability to respond to an appropriate hormonal effector and subsequently to resume meiotic maturation.
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U2 - 10.1007/BF01313467
DO - 10.1007/BF01313467
M3 - Article
AN - SCOPUS:0000118488
VL - 108
SP - 21
EP - 29
JO - Marine Biology
JF - Marine Biology
SN - 0025-3162
IS - 1
ER -