摘要
Comparing fat content with physiological status can throw light on the reproduction and feeding behavior of the fish. The biological data of 586 bigeye tuna were collected from the longline fishery in the waters of Western Central Indian Ocean from November, 2012 to March, 2013. The spatial or temporal distribution of the fat content, and the relationships of fat content with gender, round weight, gonadal maturity and fork length were analyzed. A generalized additive model(GAM) was used to analyze the relationships between fat content and fork length(FL), gonadosomatic index(GSI), condition factor(K), and somatic index(SI). Results showed that: 1) the fat content of bigeye tuna was in the range of 3.1%–27.1% with the average 12.8%; 2) there were no significant geographical differences of average fat content(P > 0.05) among 1? squares in general; 3) there were no significant differences(P > 0.05) of the fat content for different genders, months, or gonad maturity stages; 4) there was an extremely significant correlation(P = 0.000) between fat content and FL and GSI. There was no significant correlation(P = 0.051) between fat content and K. There was a significant correlation(P = 0.003) between fat content and SI. The results of this study suggest that the fat content of the matured fish was relatively stable. The survey area was in a spawning region, and the survey period was the spawning season for bigeye tuna.
Comparing fat content with physiological status can throw light on the reproduction and feeding behavior of the fish. The biological data of 586 bigeye tuna were collected from the longline fishery in the waters of Western Central Indian Ocean from November, 2012 to March, 2013. The spatial or temporal distribution of the fat content, and the relationships of fat content with gender, round weight, gonadal maturity and fork length were analyzed. A generalized additive model（GAM） was used to analyze the relationships between fat content and fork length（FL）, gonadosomatic index（GSI）, condition factor（K）, and somatic index（SI）. Results showed that： 1） the fat content of bigeye tuna was in the range of 3.1%–27.1% with the average 12.8%; 2） there were no significant geographical differences of average fat content（P 〉 0.05） among 1？ squares in general; 3） there were no significant differences（P 〉 0.05） of the fat content for different genders, months, or gonad maturity stages; 4） there was an extremely significant correlation（P = 0.000） between fat content and FL and GSI. There was no significant correlation（P = 0.051） between fat content and K. There was a significant correlation（P = 0.003） between fat content and SI. The results of this study suggest that the fat content of the matured fish was relatively stable. The survey area was in a spawning region, and the survey period was the spawning season for bigeye tuna.
基金
supported by the National High Technology Research and Development Program of China (863 program, No. 2012 AA092302)
The Specialized Research Fund for the Doctoral Program of Higher Educationn (No. 20113104 110004)
Shanghai Municipal Education Commission Innovation Project (No. 12ZZ168)
Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources (Shanghai Ocean University),Ministry of Education (No. A102091505037)
Special funding for the development of science and technology of Shanghai Ocean University (No. A2020915200002)
the Youth Scholars of Shanghai Higher Education Institutions (No. A1203514001014)
