Growth Performance of Spotted Scat (Scatophagus argus) Fingerlings At Varying Stocking Densities Polycultured with Sea cucumber (Holothuria scabra)

The study on the growth performance of spotted scat (Scatophagus argus) at varying stocking densities polycultured with sea cucumber (Holothuria scabra) was conducted at the College of Fisheries Laboratory and Research Station , Bawing, General Santos City for a period of 60 days from February 23 — April 24, 2019. Nine (9) cages (1m x 1m x 1.5m) were used as enclosures for the experimental animals and installed in a pond. The bottom of each cage was enclosed in a box measuring 1x1x0.4 m and provided with sand as substrate for sea cucumber. A complete randomized design was used with three treatments replicated thrice. Feeding was done 3x a day at 8 AM, 12NN and 4 PM. A 10% feeding rate was used. The treatments were as follows: Treatment I (15 spotted scat: 5 sea cucumber); Treatment II (25 spotted scat: 5 sea cucumber) and Treatment III (35 spotted scat: 5 sea cucumber). After 60 days of culture, spotted scat in Treatment II obtained the highest mean body weight with 32.8 g, followed by Treatment I with 31.7 g and Treatment III with 31.5 g. Highest mean weight gain of spotted scat was observed in fish in Treatment II with 18.8 g followed by Treatment I with 17.7 g and the lowest in Treatment Ill with 17.5 pg. Mean daily growth was highest in Treatment II (0.40 g/day), followed by Treatment I (0.36 g/day) and lowest in Treatment III (0.35 g/day). On the other hand, mean body weight (57g) and mean weight gain (50g) of sea cucumber were highest in Treatment III followed by Treatment II (55 g and 48 g)) and Treatment I (54 g and 47g). Analysis of variance showed no significant difference among treatments (P>0.05). Survival rate of both fish and sea cucumber was 100%. The FCR of the fish in Treatment I, II and III were 2.7, 2.6 and 2.7 respectively. Analysis of variance showed no significant difference among treatments (P>0.05). Water quality parameter reading for salinity, temperature, dissolved oxygen, pH, and water transparency were 20.5-32.3 ppt, 29.5-31.9°C, 4.1-5.2 ppm, 6.7-7.3, and 45-75 cm, respectively. The study revealed that combination of Treatment II (25 spotted scat with 5 sea cucumber) suggests that the combination of the two species is feasible.