Study of body composition changes in different age and weight of freshwater crayfish, Astacus leptoductylus

In this study chemical body composition of fresh water crayfish in different stages were investigated. So they were release about 10000 juveniles in earthen pond. Sampling was done in three different stages of crayfish، 1 month، 4 month (3-4g) and 16 month (7-9g، 10-14g and 15-20g) after separation as sex، chemical composition of different parts of body (Chelae، carapace shell، viscera، abdomen meat، abdomen shell and tail) were determined. Fat and ash levels were increased as crayfish age developed. Fat، protein and fiber levels in experimental crayfish were estimated 2-3. 5%، 37-45% and 33-35% respectively. Mean values of body chemical composition indicated no significantly differences between male and female crayfish (P>0. 05). In addition، the maximum protein levels in abdomen meat (in male and female 74. 13% and 72. 8% respectively) and the maximum fat levels in viscera (in male and female 8. 43% and 10. 49%) of this species were measured. Abdomen shell، carapace shell and tail were important organs containing of fibers with the range of 15-16 percentages. Ash values in different parts of body were between 30 to 50 percentages and minimum value of that was determined in abdomen shell with 8 percentage. There was significantly differences among chemical constituents in various organs of body (p<0. 05).