期刊
AQUATIC LIVING RESOURCES
卷 14, 期 5, 页码 313-318出版社
GAUTHIER-VILLARS/EDITIONS ELSEVIER
DOI: 10.1016/S0990-7440(01)01126-3
关键词
GSI; reproduction; steroid hormone; tuna
A total of 361 skipjack tuna (Katsuwonus pelamis) between 41.5 and 71.5 cm fork length and 333 yellowfin tuna (Thunnus albacares) between 48 and 150 cm fork length were collected in the western Indian ocean, between latitude 5 degrees N to 10 degrees S and longitude 45 degrees to 65 degrees E from February 1989 to November 1990. Yellowfin populations have one major reproductive season during the north monsoon while in skipjack the reproduction is almost continuous all year round with two peaks in activity during north and south monsoons. The gonadosomatic indexes (GSI) are correlated with the three climatic situations: the north monsoon, the south monsoon and two inter-monsoon seasons. The steroid hormone variations (oestradiol, oestrone. and testosterone) are well correlated with the GSI in females. In males, maximum levels coincided with the two main reproduction periods in skipjack while the maximum values of testosterone and 11-ketotestosterone levels were only found during the north monsoon. Even if both species are continuous spawners, these results indicate the existence of different reproductive traits, especially when considering steroidogenesis and vitellogenesis. These findings suggest that over our fishing zone, the reproductive activity is significantly modulated by climatic changes. (C) 2001 Ifremer/CNRS/Inra/IRD/Cemagref/Editions scientifiques et medicales Elsevier SAS.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据