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黄鳍金枪鱼(Thunnus albacores)是3个热带金枪鱼鱼种之一,也是我国远洋金枪鱼渔业的主要捕捞对象之一。本研究根据我国金枪鱼渔业观察员在热带太平洋海域(14°1’S-11°41’N,158°43’E-128°24’W)采集的229尾雌性黄鳍金枪鱼样本,基于组织切片法对其繁殖生物学特征进行研究。结果表明:成熟度以Ⅰ、Ⅱ期为主,性成熟个体占样品总数的36.7%;运用Logistic模型拟合的性成熟比率(P)与叉长(L_F)关系曲线(成熟度曲线)方程为P=1/1+e~([-0.072(LF-138.13)]),对应的50%性成熟叉长为138.13 cm;在南半球,纬度越高,性成熟比率和性腺成熟指数越高。东太平洋和中西太平洋(以150°W为界)黄鳍金枪鱼群体的成熟度表现出区域性差异,东太平洋群体的成熟进程比中西部快,且产卵活动存在季节性差异。东太平洋和中西太平洋群体成熟度的性腺成熟指数变化规律相似。比较肉眼观测法和组织切片法,发现肉眼观测法对Ⅱ、Ⅴ期的判断准确率较高,对Ⅰ、Ⅳ期的判断准确率低。
Thunnus albacores is one of three tropical tuna species and one of the main fishing targets for China’s ocean tuna fisheries. Based on the results of histological sectioning, a total of 229 female yellowfin tuna samples collected by the tuna fishery observer in the tropical Pacific Ocean (14 ° 1’S-11 ° 41’N, 158 ° 43’E-128 ° 24’W) Breeding biological characteristics were studied. The results showed that the maturity was mainly in stage Ⅰ and Ⅱ, and the sexually mature individuals accounted for 36.7% of the total samples. The equation of Maturity Ratio (P) and length of fork (L_F) fitted by Logistic model was P = 1/1 + e ~ ([- 0.072 (LF-138.13)]), the corresponding 50% maturity length was 138.13 cm. In the southern hemisphere, the higher the latitude, the higher the sexual maturity ratio and gonad maturation index. The maturity of the yellowfin tuna populations in the eastern and western and western Pacific (at 150 ° W) showed regional differences. The maturation of the eastern Pacific population was faster than in the central and western regions, with seasonal differences in spawning activities. The law of gonad maturation index of maturity of the East Pacific and Western and Central Pacific Ocean is similar. Comparing the macroscopic and histological sections, it was found that the macroscopic observation method had a higher accuracy of judging stage Ⅱ and Ⅴ, and lower accuracy of stage Ⅰ and Ⅳ.