The Effects of Salinity Stress on Growth Rate, Hematological Parameters and Survivability in Shirbot Fingerlings(Arabibarbus grypus)

Inroduction & Objective: The growth rate and survivability and blood parameters level are as the base of studies in environmental stress in fish body. The goal of this study is to find the effect of different salinity stress on blood parameters in reared shirbot (Arabibarbus grypus) fish for determine the suitable condition of growth and survivability and physiologic tolerance during transforming into the waters with different levels of salinity. For this purpose, 120 pieces of baby fish with total length: 15±5 cm, mean weight: 30±5 gr in 300 liter fiberglass tanks, mean temperature: 25.16±1.47Ċ, include four different salinity concentrations :<5 P.P.T , 10 P.P.T , 15 P.P.T with 3 replicant during 30 days were raised. The fish were fed with concentrated food 3% body weight twice a day. The fish biometric for growth assessment at the beginning and at end of the course. After 30 days, growth factors (increase body weight%, special and daily growth rate), survival and then blood parameters (Hb, HCT, RBC, WBC, Lymphocyte, Monocyte, Neutrohpil, MCV, MCH& MCHC) were measured. According to the results, salinity increase cause to significant decrease of; increase body weight%, special and daily growth rate and survival (P<0.05). Also no significantly difference of the blood parameters regarding to effect of salinity stress on fishes seen (P>0.05), but neutrophil shows significant increase and maximum level of it was in 15 PPT. Based on the results, considering the reduction of growth factors and survival rates with increasing salinity, especially in salinity higher than PPT5, although blood parameters were not affected by the adaptation process, but fresh water seems to be the best treatment and salinity of PPT5 By controlling other environmental conditions, the maximum salinity (critical limit) of water is for the economic development of the young fish.