Pond Based Juvenile Production of Siganids: Growth Performance of 30-Day Post Hatch Siganus guttatus (Bloch, 1787) at Three Stocking Densities

Abstract

Growth performance, survival and profit index of 30-day post hatch Siganus guttatus (0.08 ± 0.09 g and 1.60 ± 0.15 cm) of the same age group was evaluated for 60 days in hapa net cages (1m wide x 1m long x 1m deep) in pond based conditions. Three stocking densities were replicated three times and laid out using Completely Randomized Design (CRD). The three treatments were: 1(T1)-250 fish m -3 ; 2 (T2)-500 fish m -3 and 3 (T3)-1000 fish m -3 . Growth performances (final weight, weight gain and specific growth rate) and survival rates of juveniles stocked in 250 fish m -3 was significantly higher (P < 0.05) than those fish stocked at 1000 fish m-3. However, growth performance and survival rates between 250 fish m -3 and 500 fish•m -3 were not significant. Feed conversion ratio (FCR) was significantly lower (P<0.05) in T1 than T3. However, FCR was not significant between fish stocked in T1 and T2. Net profit was higher in fish stocked in T2 compared with T1. Among the stocking densities of S. guttatus evaluated, 500 fish•m -3 appeared as the optimal stocking density based on growth, survival, FCR and profit index.

Effects of protein levels of commercial diets on the growth performance and survival rate of rabbitfish (Siganus guttatus) at the nursing stage

“…The results of this study are in agreement with the findings of Andam et al (2016) who reported a 23.90 mm increase in the S. guttatus during the fingerling period.…”

“…Another study by Hieu et al (2018) found these proteins contents levels in diets also showed the highest value of growth rate. The survival rate in this study was higher than that reported by Andam et al (2016) when using a diet with a protein level of 30 -40%, which was mentioned as the best growth of the species at 40% CP in the diet. However, the species in the brackish water of Tam Giang lagoon had different characteristics, there was no successful result by artificial reproduction yet and there were still more biological mysteries.…”

“…Water temperature also plays an important role in aquaculture and the temperature range from 27.66 to 32.55 °C, is suitable for the species that live in warm water ranges from 25 to 32 °C as mentioned by Carumbana and Luchavez (1979) and Boyd (1998). Further, dissolved oxygen (DO) ranged from 4.33-5.45 mg L -1 , salinity ranged from 28 to 29%, and total ammonia (NH4/NH3) ranged from 0.67 to 0.81 mg L -1 are suitable water characteristics for fish culture (Rahman et al, 2009;Andam et al 2016). In general, the water environmental factors recorded in this study are within the threshold of good growth and development of fish, and in this study levels of 30, 35, 40, and 45% of dietary protein percentages have not affected the water environmental quality for fish culture, therefore, water control was evaluated every day by leaning of tank bottom, as mentioned the water control by Parazo (1990) and Salem et al (2021).…”

Effects of protein levels in commercial diets on growth performance and survival rate of rabbitfish (Siganus guttatus) at the nursing stage

“…In addition to increase in weight, increases in length is an important factor to evaluate during the development in the ngerling stage. This study showed that the average growth belongs the length of sh from 30 to 60 days old (Table 3), detail growth of sh at 35% CP reached 36.92 mm sh -1 which was lower than that those in the 45% CP feed group, which had a length of 38.89 mm sh -1 (p < 0.05) but was not distinct from the remaining 40% CP fed group (37.97 mm sh -1 ); meanwhile, the increase in length of formulas 1, 2 and 3 reached 18.66, 19.73 and 20.62 mm sh -1 , respectively (p > 0.05), and the length of S. guttatus during the ngerling period increased to 23.90 mm (Andam, 2016). Daily length growth (DLG) of the 3 experimental treatments were as follows:…”