Effects of dietary butyric acid on salinity stress condition in Caspian roach (Rutilus caspicus)

In the present study the effects of dietary butyric acid on growth indices and resistance against salinity stress in Caspian roach (Rutilus caspicus) have been studied. In this regard, 300 fish with average weight of 10 ± 1.03 were divided in 15 fiberglass tank with dimensions of 1.5 × 1.5 m and 60 liters watering capacity (20 fish per tank). In this study 3 treatment groups and one control (in three replicates) were considered, after two weeks adaptation treatment groups were fed with different levels including: 0.5, 1 and 2 % of dietary butyric acid for 60 consecutive days. Control fish just fed with basic diet. After rearing period all fish were exposed to salinity stress at 10 g/l for 12 hours and stress indices (cortisol and glucose) were monitored during 72 h post challenge. Results showed growth indices in all treatment groups that fed with different levels of butyric acid were significantly recorded lower in compare to control one (). On the other hands cortisol level in control group during 72 h post challenge were lower compare to the fish that fed with different levels of butyric acid which indicate an increase in stress in fish of treatment groups against salinity stress condition.