标题：EVALUATION OF STOCKING DENSITIES AND FEEDTYPES ON GROWTH AND SURVIVAL OFNARROW-CLAWED CRAYFISHPONTASTACUS LEPTODACTYLUS (ESCHOLTZ, 1823)REARED UNDER LABORATORY CONDITIONS
摘要：Type o f feed and stocking density are two main factors affecting production parameters, such as growth, m olting, and survival rate o f crayfish. The aim o f this study was to investigate the effects o f two different diets and three stocking densities in six treatments on the growth and survival o f crayfish (Pontastacus leptodactylus). A total o f 258 crayfish were used in flow-through system at the Aquaculture Research Facility located in Iskenderun Technical University, Hatay, Turkey for 120 days. The experiment was carried out in a completely randomized design w ith 3x2 factorial having three stocking densities (D ensityl: 25 crayfish m-2, Density2: 75 crayfish m-2 and Density3: 225 crayfish m-2) and two diets (D ie tl: Trout feed and Diet2: fish meat). A ll treatments were replicated three times. Results showed that the mean total yield in Diet2 (307.73 g) was higher than D ie tl (282.18 g) but the difference was not significant (p>0.05) and this parameter was significantly higher in Density3 (471.00 g) than Density2 (83.60 g) and and D ensityl (35.31 g) (p<0.05). Mean survival o f crayfish was found to be higher in Diet2 (53.48%) than Diet1 (44.18%) the difference was not significant (p>0.05). Sim ilarly, survivability o f crayfish in Density 1 (91.67%) was significantly higher (p<0.05) than in the other treatments. The treatment w ith fish meat (Diet2) and low stocking density was superior in terms o f higher mean survival and growth parameters. The negative relationship was found between stocking density and average body weight for P. leptodactylus. Commercial trout feed and stock density (20-75 m-2) was found to be the most ideal at the end o f the study. Hence, stocking density and feed type should be carefully managed in larval stage crayfish culture.
