Effects of Salinity on Growth Performance and Blood Parameters o Butter Catfish, Ompok bimaculatus

The study was conducted in laboratory conditions to evaluate the effects of salinity on growth, survival, and blood chemistry of butter catfish, Ompok bimaculatus fingerlings. The fry, initially sized as 7.01 cm length and 1.69 g weight, were assigned in four different salinity treatments i.e., 0 ppt (T-C), 2 ppt (T-1), 4 ppt (T-2) and 8 ppt (T-3) with three replications, with 21 fry in each replication as well. Fish were fed commercial catfish diets with 43% protein and 8% lipid at 5% body weight three times a day for 90 days. The control (T-C) treatment showed the significantly highest growth performance among treatments, (p<0.05). The T-3 treatment group showed a lethal parameter and all fish died within 72 hours of exposure to it. The survival rate was recorded as 90.47% for T-C, 71.43% for 1, and 47.61% for T-1, treatment. The mean weight and length gain 6.17 g and 4.93 cm observed in T-1 followed by 4.59 g and 3.06 cm in T-2 treatment. The specific growth rate (SGR) (%) mean weight gain, length gain, average daily weight gain, average daily length gain and percentage length gain were (%) found to be significantly higher in T-C in comparison to those in the salinity treated groups (p<0.05). Significantly higher hemoglobin and WBC were observed in T-C among treatments and had the lowest value recorded in T-1 and T-2. There were no significant changes between RBC counts among treatments.