The study of adaptation, growth and survival of tilapia (Oreochromis.sp) in Bafgh brackish water

Abstract

An experiment was conducted to evaluate the possibility of adaptation, growth and survival of Red and Nile tilapia (Oreochromis niloticus) in underground brackish water. Fry with 0.3 and 0.7 g initial weight imported from Indonesia and after passing larviculture (20 g) were examined separately in fiber glass tank and earthen pond by two replicate. Fish were fed three times a day by using manual food (cp = 33.79) and carp food (cp = 25.05) at a restricted feeding program according to standard table during the 72 days rearing stage at light period. The results showed that some growth factors such as final weight, final length, daily growth rate, specific growth rate and weight gain in Nile tilapia were slightly higher than red tilapia but other factors such as survival and feed conversion rate in red tilapia were slightly higher than Nile tilapia. There were no significantly differences at 99% level among these factors. Length-weight relationship equation was w = 0.020 × TL3.012 in Nile tilapia and w = 0.015 × TL3.086 in red tilapia (r2 = 0.98), b value was 3.012 and 3.086 respectively in Nile and red tilapia representing isometric growth. So according to the results, good growth and high survival rate, it seems that both Nile and red tilapia could be good candidates for reproducing and rearing in brackish water condition.