Observations on the biochemical changes in gonads and other organs of Uca annulipes,Portunus pelagicus and Metapenaeus affinis (Decapoda: Crustacea) during the reproductive cycle

The fluctuations in biochemical constituents such as water, nitrogen, non-protein nitrogen, protein, lipid and glycogen in gonad, muscle and hepatopancreas have been followed in 3 decapod crustaceans, Uca annulipes (Latreille), Portunus pelagicus (Linnaeus) and Metapenaeus affinis (Milne-Edwards). The water and ash content of the entire body show no systematic fluctuation in relation to the annual reproductive cycle. The water content of the ovary diminishes as it matures. In the ovary of these crustaceans, the lipid fluctuated greatly in relation to the reproductive cycle. The maturing ovary contains more lipid than an immature or spent ovary per unit tissue weight. The changes in the biochemical constituents in the testis are not so pronounced as in the ovary, since the testicular cycle is often drawn-out and almost continuous in these crustaceans. There is an inverse relationship between water content and lipid content of the hepatopancreas; the greater the fat content, the lesser the water content. The hepatopancreas in these crustaceans is apparently a storage organ and contains much lipid and glycogen. At the height of the breeding season, when gonad production is intense, there is an indication of the mobilisation of at least a part of the lipid from hepatopancreas to gonad.Dissertation for the award of a Doctorate Degree of the Kerala University.Formerly the Marine Biological Laboratory.