Study of growth indices, survival and resistance to Salinity stress of Caspian roach (Rutilus rutilus caspicusJakowlew,1870) fed by diet comprising of black Cumin seed

In recent years, use of herbs as dietary growth stimulant factor and replacing it with artificial materials in aquaculture is widely discussed. The impact of black cumin seed (Nigella sativa)powder at four levels of 0, 0.5, 1 and 2 percent, per kilogram of diet, on growth, survival and resistance to salinity stress in the Caspian roach (Rutilus rutilus caspicus) was investigated for 60 days. At the end of the study, growth factor and feed conversion factorwere calculated. In addition,the effect of black cumin seed powder on resistance to salinity stress was investigated, in intervals of 24, 48 and 72 hours.The results showed that using black cumin seed, up to the 0.‌5 percent, cause highest body weight gain (7.09±0.38), specific growth rate (1.59±0.04), condition factor (0.11±0.006) and lowest feed conversion factor (1.29±0.08) in fingerlingroach. Statistical analysis showed significant differences (p< 0.05) in growth indices and feed conversion factor, between treatments and the control group. This study showed that black cumin seed powder in the diet, despite increased growth performance in roach, lacked positive effect on the resistance to salinity stress in the fish.