Excretion in estuarine animals is considered to be an important factor in assessing their physiological status. The pattern of oxygen consumption and excretion patterns (ammonia and nitrite) in medium size mud crabs of S. quadratum (3 to 4 g weight) were studied under laboratory conditions at two sublethal concentrations of 1/10 and 1/3 of the LC50 value of copper chloride and chlorine. The rates of oxygen consumption and excreted products were negatively correlated to the sublethal concentrations of the toxicant. Reduced rates of oxygen consumption and excretion of ammonia and nitrite were observed when exposed to these sublethal concentrations.

Excretion in estuarine animals is considered to be an important factor in assessing their physiological status. The pattern of oxygen consumption and excretion patterns (ammonia and nitrite) in medium size mud crabs of S. quadratum (3 to 4 g weight) were studied under laboratory conditions at two sublethal concentrations of 1/10 and 1/3 of the LC50 value of copper chloride and chlorine. The rates of oxygen consumption and excreted products were negatively correlated to the sublethal concentrations of the toxicant. Reduced rates of oxygen consumption and excretion of ammonia and nitrite were observed when exposed to these sublethal concentrations.