DIRECT CALORIMETRY OF AQUATIC ANIMALS - AUTOMATED AND COMPUTERIZED DATA-ACQUISITION SYSTEM FOR SIMULTANEOUS DIRECT AND INDIRECT CALORIMETRY

A system for computerized registration of heat production data and oxy gen tension values of a differential 1 litre flow-through microcalorim eter (Setaram GF 108) is described. The linked values of oxygen concen tration and heat production data were simultaneously stored on a compu ter. The aerobic and total heat production rates were thus measured of goldfish (Carassius auratus L.) during normoxia, hypoxia and anoxia e xposure. Incidentally, a partial anaerobic response was observed in go ldfish during normoxia. During severe hypoxia and anoxia, goldfish res pond with a reduction of the metabolic rate and a strong increase of a naerobic heat production. From the linked oxygen consumption and heat production data, the oxycaloric equivalent was calculated. The describ ed system enables us to study continuously the effects of environmenta l factors on the metabolic rate of aquatic organisms.