Biochemical composition and changes in biological indices associated with maturation of the ovary in the spiny cheek grouper Epinephelus diacanthus (Valenciennes, 1828)

Changes in biological indices (gonadosomatic index GSI, hepatosomatic index HSI and condition factor) and biochemical composition of body tissues and serum, associated with ovarian development were examined in Epinephelus diacanthus sampled for two years. GSI, HSI and Condition factor values increased with the maturation of gonads. Mobilisation of biochemical constituents from somatic tissues to the gonadal tissues with the maturation of the ovary was noticed. Highest protein percentage was in stage III (24.81%) ovary. The total lipid percentage of the ovary showed a gradual increase from Stage I (6.56%) to Stage III (13.48%). Total cholesterol showed a steady declining trend and carotenoid levels of the ovary showed a positive relationship with ovarian maturation. Ash content of the ovary increased from stage I (0.82%) to stage III (1.20%)