AMMONIA EXCRETION OF THE SAND-SHRIMP CRANGON-CRANGON (L) DURING THE MOLT CYCLE

Ammonia excretion in the shrimp Crangon crangon (L.) shows a cyclical pattern during the moult cycle. At the early premoult (stage D0) there is a 7 to 17% increase over that characteristic at intermoult; at late premoult (stage D2) excretion decreases to a minimum; immediately after ecdysis, the excretion rate is 1.5 to 2.6 times higher than at the intermoult stage (Table 1). These variations appear to be correlated with protein breakdown and protein synthesis, and possibly with periods of high metabolic activity (growth resulting from cell multiplication). Ammonia excretion of animals in standing water is higher than of those in running sea-water. Excretion might possibly be influenced by a semi-lunar rhythm. © 1979, Springer-Verlag. All rights reserved.