Effects of Water Salinity on Feeding Efficiencies, Growth Performances and Survival Rate of Thai Strain Koi, Anabas testudineus (Bloch, 1792)

2 Abstract: The study was carried in three rectangular glass tanks with two replications of each where the first tank was considered as control, C (salinity 0 ppt), the second as Treatment 1, T (8 ppt) and the third as 1 Treatment 2, T (10 ppt). 72 fry (average weight 2.5g) were stocked in these tanks at one feeding rates 2 (3% of body weight) in a 1 X 2 factorial experiment. The fishes were fed at morning and afternoon in a day. Average food conversion ratios (FCR) were found 2.67±0.371, 2.27±0.351 and 2.07±0.56 in C, T and T where 12 average protein efficiency ratios (PER) were 0.67±0.078, 0.8±0.056 and 0.76±0.068 in three tanks respectively. The feed efficiency (FE) were T : 22.31±3.07%, T : 21.38±2.99% and C: 26.42±2.93% and specific growth rate 12 (SGR) were 0.67±0.139 %/d in the C, 0.99±0.357%/d in T and 0.79±0.326 %/d in T respectively. Average daily 12 gain (ADG) was found higher in T (0.15±.011 g/d), than in C (0.12±0.305 g/d) and in T (0.14±0.037 g/d). 12 The condition factor (CF) was 0.29±0.030 % in C, 0.38±0.019 % in T and 0.35±0.022 % in T The final weight 1 2. gain (g) was obtained 35.94±0.402g, 36.07±0.4g and 36.03±0.316g in C, T and T where final length gain (cm) 12 was obtained 7.56±0.184cm, 7.68±0.18cm and 7.49±0.17cm in C, T and T respectively. Also survival rates were 12 found 91.67%, 100% and 95.83% in C, T and T. The proximate compositions of fishes were also better in T 12 1 than that of T and C. Water quality parameters were also found better in T than that of T and C. It was 2 12 observed that feeding efficiencies and growth performances were better in T than that of T and C. The best 12 growth was found from T and lower growth was found from C in case of Thai strain koi (Anabas testudineus). 1 The present study revealed that Thai Strain Koi can tolerate a wide range of salinity and also better growth could be possible to find than in freshwater.