Effects of releasing weight on growth, survival and hematological indices in silver carp (Hypophthalmichthys molitrix, Valenciennes, 1844)

In the present study, the effects of releasing weight on reared silver carp's growth and survival, as well as, its hematological indices were assessed. For this purpose, first eight 3-hectares ponds were divided into four treatments based on fishes' releasing weight equal to 2, 3, 4 and 5 g, then sampling from these animals was periodically done and the hematological indices were measured. At the end of the trial, the average weight of fishes (g) and total production of each pool (kg) was calculated. The results of the measurement of blood parameters indicated that the hematocrit percent was significantly increased following the releasing weight enhancement (P<0.05), but any statistical relationship was seen between the stocking weight and other blood indices (P>0.05). Furthermore, the growth and survival findings signified, whereas after releasing the weight of fishes, their final weight and growth rate were enhanced, the special growth rate was reduced statistically (P<0.05). Hence, based on present results, it will be achieved proper growth whenever silver carps are stocked 12000 individuals with 5 g weight.