COMPARATIVE STUDY ON THE PROXIMATE COMPOSITION AND FATTY ACID PROFILES OF LIVER, GONAD AND MUSCLE IN MALE AND FEMALE Plotosus canius.

Abstract

The present study evaluated the proximate composition and fatty acid profile of Plotosus canius with respect to sex in order to understand potential biochemical differences between male and female individuals collected from the south-eastern coastal waters of Bangladesh, including the Kattoli mangrove forest (Chattogram) and the Moheshkhali channel (Cox’s Bazar). Proximate parameters such as moisture, protein, lipid, and ash were analyzed to assess overall nutritional quality, while detailed fatty acid composition including saturated (SFA), monounsaturated (MUFA), and polyunsaturated fatty acids (PUFA) was determined to evaluate the health-related lipid characteristics of the species. Morphometric analysis revealed that males attained greater total length and body weight than females. Length– weight relationship analysis indicated positive allometric growth in both sexes, with regression coefficients (b) of 3.13 for males and 3.28 for females. Proximate composition analysis demonstrated significant tissue- and sex-dependent variations. Muscle protein content was significantly higher in females than males (p < 0.05), whereas liver protein content did not differ significantly between sexes. Hepatic lipid content was markedly higher in males (p < 0.001), while muscle lipid levels showed no significant sex-based variation. Moisture content was significantly higher in male liver tissue, whereas ash content was significantly greater in female liver. Fatty acid profiling revealed pronounced sexual dimorphism across muscle, liver, and gonadal tissues. Female muscle tissue exhibited higher total saturated fatty acids (ΣSAFA), monounsaturated fatty acids (ΣMUFA), and n-6 polyunsaturated fatty acids (PUFA), while male muscle contained higher n-3 PUFA, including eicosapentaenoic acid (EPA). In liver tissue, females showed substantially higher ΣSAFA and ΣMUFA, whereas males displayed elevated n-6 PUFA. Gonadal tissues showed the most distinct differences, with males exhibiting significantly higher ΣSAFA and n-3 PUFA, while females accumulated greater ΣMUFA and selected n-6 PUFA associated with reproductive functions. Atherogenicity index (AI) and thrombogenicity index (TI) varied significantly among tissues and sexes. Liver tissue showed the lowest AI and TI values in both sexes, indicating favorable lipid quality, whereas the highest values were recorded in male gonads. Overall, VIII the findings demonstrate that sex and tissue type strongly influence nutritional composition, fatty acid distribution, and lipid health indices in P. canius. These results provide valuable insights into sex-specific lipid metabolism, reproductive physiology, and the nutritional importance of this species for human consumption and fisheries management in coastal Bangladesh.