MARRON (CHERAX-TENUIMANUS) AND NOBLE CRAYFISH (ASTACUS-ASTACUS) HEPATOPANCREAS ENERGY AND ITS RELATIONSHIP TO MOISTURE-CONTENT

Hepatopancreas energy and moisture content were analyzed in farmed and wild-stock marron and wild-stock noble crayfish. Marron were sampled during April 1995 and noble crayfish during September 1995. Total hepa topancreas energy content was analyzed by bomb calorimetry and moistur e content was determined from fresh hepatopancreases by oven drying to constant weight. Farmed marron had significantly higher hepatopancrea s energy content (31.0 +/- 0.4 kJ g(-1)) than wild-stock matron (26.7 +/- 0.6 kJ g(-1)), indicating better condition in farmed stocks. Wild- stock noble crayfish had similar hepatopancreas energy content (29.3 /- 0.3 kJ g(-1)) to farmed marron and significantly higher levels than wild-stock marron. The relationship between hepatopancreas energy and moisture content was linear in both species with coefficients of dete rmination (r(2) = 0.44 and 0.73 for marron and noble crayfish, respect ively). A rapid method of determining freshwater crayfish hepatopancre as energy using moisture content is suggested.