Growth performance and proximate composition of grey mullet Liza parsia at different salinities

Abstract

The study was conducted to evaluate growth, survivability, and proximate composition of Liza
parsia at different salinities to adopt as a potential aquaculture species in salinity intruded coastal areas of
Bangladesh. The experiment was carried out at laboratory conditions in rectangular tanks (25 L) with five
different salinities viz. 0, 5, 10, 15 and 20 ppt correspondingly considered as T1(control), T2, T3, T4 and
T5. Fingerlings were collected from the Pashur river and stocked at 10 individual/25L tank. After 90 days of
culture period, growth was found significantly different among the treatments. Average weight gain was
highest inT2 (1.76±0.19) and lowest inT5 (0.91±0.15). Interestingly survival rate was found 100(%) in all
treatment. Specific growth rate was 0.829±0.10, 1.162±0.14, 0.744±0.2, 0.736±0.10 and 0.605±0.15
respectively in T1, T2, T3, T4 and T5. Average daily gain was found higher in T1 (0.059± 0.006g/d),
compared to other treatment. The average food conversion ratios were 0.78±0.06, 1±0.00, 0.69±0.06,
0.78±0.22 and 1.035±0.25 in T1, T2, T3, T4 and T5 in five tanks, respectively. Better water quality
parameters were observed in T2. The temperature ranged from 28-30.3ºC, pH from 7.21-7.64, DO from
5.01-5.68 ppm, hardness from 184.55-237.65mg/l and total ammonia nitrogen (TAN) ranged from 0.52-0.85
mg/l. No significant change was observed in the proximate composition of fish reared at different salinities.
Finally, it could be concluded that L. parsia can tolerate a wide range of salinity and can be cultured even in
freshwater, thus might be a potential species for coastal aquaculture.