Dan D. Baliao

Economic feasibility analysis of the monoculture of mudcrab (Scylla serrata) Forsskal

Mudcrabs, Scylla serrata Forsskal, were monocultured at different stocking densities: 5000, 10 000, 15 000 and 20 000/ha for 90 days. Highest mean weight, survival and relative growth increment (P<0.05) were obtained from a stocking density of 5000/ha. Best feed conversion ratio of 1.72 and corresponding gross production of 1019 kg/ha per crop were attained at the same stocking density. The economic indicators, i.e., return on investment and return on equity, were also highest at 5000/ha stocking density and the payback period was shortest. Partial budgeting showed that no incremental benefit accrued from stocking beyond 5000/ha. Sensitivity analysis showed that even if the value of mudcrab were to decrease by 28%, mudcrab monoculture would still be economically viable.

An economic analysis of the modular pond system of milkfish production in The Philippines

Abstract In 1980, the annual yield of milkfish ponds in The Philippines was 800 kg/ha while the potential yield is estimated to be 2000 kg/ha. The modular pond system analyzed in this study can largely close the gap between actual and potential yield through more efficient use of pond capacity to increase the number of croppings up to 7 times in 1 year. Pilot-scale production using the modular pond system was done at the Leganes Research Station (LRS) SEAFDEC, Iloilo, and at three cooperating commercial farms. Scale of operation ranged from 2.7 ha to 7.9 ha. From 2 to 7 production runs were recorded with per hectare outputs ranging from 278 kg to 341 kg per run. Input costs were based on actual figures and the ex-farm milkfish price as P21.00 (4 to 6 fish/kg). The average return on investment and payback period for all sites was 68.81% and 1.25 years, respectively.

The economics of retarding milkfish growth for fingerling production in brackishwater ponds

Abstract Two experiments were conducted to measure the economic viability of retarding milkfish growth (stunting) in brackishwater ponds. In the first experiment, 2-month-old fish were reared for 6 months in ponds with initial stocking densities of 15, 20, 25, and 30 fish/m 2 . The second experiment had a common stocking density of 20 fish/m 2 with rearing periods of 6, 9, and 12 months. All experiments followed the lab-lab method of growing natural food plus additional substrates. Supplemental feeding using rice bran mixed with ground trash fish started 60 days after initial stocking. Under Philippine conditions stunting milkfish fingerlings at 20 fish/m 2 for 6–9 months is most cost effective; this permits the production of milkfish fingerlings for lower cost than they can be purchased.

Comparison of the silo and broadcast methods of applying organic fertilizer in milkfish, Chanos chanos (Forsskal), ponds

Abstract The efficacy of the silo and broadcast methods of applying organic fertilizers in ponds for the production of pond-floor, microbenthic biological complex, a natural food source known as lablab, was tested in 1-ha ponds, replicated thrice in time. Although there were no statistically significant differences (P > 0.05) in milkfish growth, survival and production between the two treatments tested, after 90 days production tended to be higher in ponds prepared with the silo method. Advantages of the silo method are that it is less laborious, cheaper, and less time consuming than the broadcast method and results in consistent lablab growth until the end of the culture period.