Objective   Nutritional compositions in the meat of female and male Murray cods (Maccullochella peelii peelii) at critical growth stage were determined for feed improvement of the aquaculture.

  Method   Contents of protein, amino acids (AAs), fat, and fatty acids (FAs) in the filets were analyzed for the evaluation.

  Result   Significant differences were found on fat and protein contents between the female and male fish fillets. Among 17 AAs, there was no significant difference between the females and males on cystine (Cys) or histidine (His) (P＞0.05). However, the females had extremely significantly higher contents of the other AAs than the males (P＜0.01). The total AA as well as the essential, non-essential, sweet, bitter, acidic, flavoring, sulfur, branch-chain, and aromatic AAs were extremely significantly higher in the females than the males (P＜0.01). The highest content of FAs in the fish filets was C18:1n9c, followed by C16:0. The C16:0 FA in meat was extremely significantly higher for the female than the male (P＜0.01), but no significant difference on C18:1n9c. The n-3/n-6 ratios were same for the female and male at 1.0. The E/T of both female and male cods surpassed the reference protein standard at 40%, and the E/NT at more than 60%, as proposed by WHO/FAO. The SRCAA was 78% for both male and female Murray cods. The filets were rich in unsaturated FAs, i.e., 57.4% for the females and 55.4% for the males.

  Conclusion  The major nutritional components in the filets of the male and female parental Murray cods were significantly different, indicating that they ought to be fed with differently formulated forages in separate ponds. Nutritionally, the meat of either female or male Murray cods was highly recommended as a source of animal protein.