Seasonal changes in the biochemical composition of the freshwater cat-fish,Wallagonia attu (Bloch.)

Summary Seasonal changes in the various biochemical constituents of muscle, liver and gonads were studied in the cat-fish, W. attu. Distinct phases of high and low fat accumulation occurred in each tissue. Moisture in different tissues showed marked seasonal variations which were related inversely to the changes in the amount of fat. Seasonal fluctuation in protein was less pronounced in muscle and liver while in ovaries these were fairly well defined. Protein values in all the tissues were generally low during the winter. Ash content showed little variations in the three tissues. The seasonal cycles of various constituents in each tissue were correlated with the cycle of maturation and depletion of gonads. Different phases of maturation were associated with marked quantitative fluctuations of each ingredient in different tissues.