EFFECT OF TEMPERATURE AND FOOD LEVELS ON THE GROWTH AND CONDITION OF JUVENILE SEPIA-ELLIPTICA (HOYLE 1885) - AN EXPERIMENTAL APPROACH

Temperature and ration level can differentially affect growth and life history characteristics of marine organisms. In this experiment we re ared juvenile cuttlefish, Sepia elliptica, under two. feeding regimes (satiation and half satiation) and two temperature regimes (25 and 30 degrees C). This study examined differences in somatic growth, muscle tissue structure and composition as a function of temperature and food levels. We estimated body mass and the concentration of water, carboh ydrate, protein and lipid in the mantle muscle tissue for each individ ual. Both high water temperature and high feeding rations increased gr owth rates. Temperature appeared to change the rates of muscle fibre g eneration and fibre growth similarly. In contrast, the ration level al tered the relative rates of fibre production and fibre growth. The mus cle tissue of individuals reared at 30 degrees C had higher concentrat ions of carbohydrate and protein. In contrast, increasing ration level s only increased carbohydrate concentrations in the muscle tissue; The muscle tissue of reared juveniles had lower concentrations of carbohy drate and protein than wild individuals of similar size. In conclusion , water temperature and feeding levels both affect somatic growth, but the nature of the effect at the sub-organismal level differs. (C) 199 8 Elsevier Science B.V. All rights reserved.