Influence of stocking density and fertilization regime on growth, survival and gross production of Penaeus monodon Fabricius in brackishwater ponds

Abstract

Twelve 0.1 ha earthen ponds were stocked at 3,500 or 7,000/ha with 1-month old nursery reared Penaeus monodon Fabricius (1.73 g). Fertilizer treatments were 125 kg chicken manure plus 4.1 kg diammonium phosphate (18-46-0) and 6.56 kg urea (45-0-0) per application for treatments U3500 and U7000 and 125 kg chicken manure plus 8.15 kg diammonium phosphate and 0.89 kg urea per application for treatments P3500 and P7000. Fertilizers were broadcast 10 days after pest eradication and every two weeks thereafter. Water was exchanged (20%) one day before fertilization throughout the 86-day culture period. Shrimp yields at harvest were: P7000, 193.6 kg/ha; P3500, 119.4 kg/ha; U3500, 97.5 kg/ha; and U7000, 82.4 kg/ha. Mean survival for each treatment was 96.2%, 97%, 89.3% and 75%, respectively. There were significant differences in shrimp yields at harvest among treatments (p < 0.05).