FISHERIES RESEARCH INSTITUTE,MOA,TAIWAN

The fourfinger threadfin (Eleutheronema tetradactylum Shaw, 1804) is distributed throughout the Indo-West Pacific, including the coasts of India, Southeast Asia, the Philippines, Papua New Guinea, and northern Australia. It is an important marine farmed fish that has high economic value in Taiwan. Our results show that newly hatched larvae were 1.29 ± 0.02 mm in total length (TL) with 10–12 + 17–18 myomeres. Four days post-hatching (dph), the TL was 2.70 ± 0.02 mm. First feeding took places at this stage. At 21 dph, the TL was 15.10 ± 0.64 mm, and the fin ray counts showed an adult complement. The statistical model Y = 0.740 + 0.399X + 0.013X2, where Y is the mean TL (mm) and X represents the dph, explained 99.4% of the variation in growth (R2 = 0.994, n = 304). In the present study, juveniles (3.37–3.58 cm, 0.43–0.45 g) were randomly stocked at three densities for a 30-day trial, as follows: treatment A (500 fish/m3), treatment B (1000 fish/m3), and treatment C (2000 fish/m3). No significant differences in the growth parameters were observed among the treatments. Nevertheless, the highest survival rate (61.67 ± 5.83%), and lowest cannibalism rate (34.16 ± 4.16%) were observed in treatment C