Shrimp (Penaeus monodon Fabricius) production in brackishwater ponds applied varying fertilizer combinations

Source: Subosa, P. F., & Bautista, M. N. (1991). Influence of stocking density and fertilization regime on growth, survival and gross production of Penaeus monodon Fabricius in brackishwater ponds. The Israeli Journal of Aquaculture-Bamidgeh, 43(2), 69-76.Details are given of the production of Penaeus monodon in the Philippines reared in brackishwater earthen ponds applied with different fertilizer combinations, namely diammonium phosphate, urea and chicken manure. Results show that the shrimp showed higher yields in fertilized ponds, but increasing the concentration of fertilizers did not give a marked increase in yield - the excess fertilizer was wasted

Chicken manure, rice hulls, and sugar-mill wastes as potential organic fertilizers in shrimp (Penaeus monodon Fabricius) ponds

Shrimp (Penaeus monodon Fabricius) were cultured (3000 juveniles/ha) in 50-m2 earthen ponds fertilized with composted agricultural and industrial wastes at a basal application rate of 2 ton/ha. The following materials were tested: chicken manure, rice hulls, and three types of sugar-mill wastes: mudpress, boiler ash, and bagasse. After 66 days significant differences existed among treatments (P < 0.05) in mean body weight and gross production of shrimp. A significantly higher mean body weight (28.8 g) was obtained with boiler ash than with chicken manure (26.05 g) and these were followed by mudpress (25.8 g) and rice hulls (25.05 g) which were not significantly different from each other. The mean body weight using bagasse (22.0 g) was significantly lower than in the other treatments followed by the control (no fertilizer, 19.6 g). High survival rates were obtained in all treatments. The pond yields ranged from 53.7 to 86.4 kg/ha after 66 days with daily weight increments of the shrimp ranging from 0.18 to 0.41 g

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

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)

Yield of Penaeus monodon Fabricius in brackishwater ponds given different fertilizer combinations

Yields of Penaeus monodon Fabricius in brackishwater earthen ponds were determined using different fertilizer combinations in two sets of experiments. Results indicated that the use of fertilizers was vitally needed to sustain growth of shrimps at a stocking density of 5000 individuals/ha. Application of urea (45-0-0) and diammonium phosphate (18-46-0) fertilizers at nitrogen to phosphorus fertilizer rates (N:P2O5) of 15:15 and 30:15 kg/ha, together with 1 t/ha of chicken manure, was inexpensive and resulted in better yields. In another experiment, increase in the amount of nitrogen and phosphorus fertilizers did not significantly improve prawn yields, but did increase the cost of production. Different salinity levels affected survival in both experiments

Changes in shrimp feed quality and effects on growth and survival of Penaeus monodon juveniles

Five practical shrimp diets were formulated to contain 1, 10, 20, 50, and 100 g tetraethoxypropane (TEP) kg−1 diet. A diet with no added TEP served as the control. Diets were fed to Penaeus monodon (average weight 4.84 ± 0.11 g) juveniles to determine the level of fat oxidation tolerable to shrimp. Changes in shrimp feed quality were monitored by physical evaluation, thiobarbituric acid (TBA) values, fatty acid composition, and histological examination. Effects of feed quality on growth and survival of shrimp were evaluated. Results showed significant differences (P &lt; 0.05) in TBA values among treatments. Animals fed on diet 6, which contained 100 g TEP kg−1 diet, showed signs of physical deterioration after 6–8 weeks. This diet had a significantly higher TBA value (1262 mg malonaldehyde kg−1 fat) than the other treatments. The unsaturated fatty acid content of the diet decreased as its TEP content increased. Weight gains of shrimp fed diet 5 (50 g TEP kg−1 diet) and diet 6 were significantly lower than those fed the other diets while survival was similar. Hepatopancreatic lesions were not evident in all samples. Fat oxidation levels expressed in terms of TBA values of up to 828 mg mal kg−1 fat can be tolerated by Penaeus monodon juveniles in terms of growth response

Butylated hydroxytoluene: its effect on the quality of shrimp diet stored at various temperatures and on growth and survival of Penaeus monodon juveniles

Shrimp diets with and without the antioxidant, butylated hydroxytoluene (BHT) were stored at 10°, 20°, 28°–30°, and 40°C for 10 weeks. To monitor lipolysis and lipid oxidation, free fatty acid (FFA) content, peroxide values (PVs), and malonaldehyde (MAL) levels were measured from the extracted lipids of the stored diets. Fatty acid levels of the diets increased between the initial and final samplings and the increase was higher (8.4%) in diets without BHT stored at 40°C after 10 weeks. Peroxide values of the extracted lipids were low and fluctuated monthly between 2.2 and 7.4 mmol/kg fat. MAL levels increased in diets with and without BHT except those stored at 10°C for 4 weeks. Diets with BHT stored at 10°C had the lowest (8.7 mg MAL/kg fat) MAL levels and diets without BHT stored at 40°C for 10 weeks had the highest (16.9 mg MAL/kg fat). Shrimp fed diets with BHT gained 5.7–6.4× their initial weight after 10 weeks of rearing. Their growth was significantly better than those fed diets without BHT (4–6×) during the 60-day culture period. Survival was significantly higher in those fed diets with BHT (87–88%) than those without BHT (75–85%). No hepatopancreatic lesions were seen in shrimp samples fed diets with and without BHT and stored at various temperatures. The incorporation of BHT in shrimp feed is necessary if the feed is to be stored at 40°C for 10 weeks.The author wish to thank the International Foundation for Science for funding this study

Evaluation of organic and inorganic fertilizers in brackishwater milkfish ponds

Contribution No. 321 of the SEAFDEC Aquaculture Department.The study was conducted in twelve 144-m2 ponds to evaluate the effect of different organic and inorganic fertilizers on the growth, survival, gross production, and profitability of marketable milkfish. The following treatments were used: Treatment I, SEAFDEC traditional fertilization practice (16-20-0 at 50 kg/ha and 45-0-0 at 15 kg/ha); Treatment II, half-dosage of Treatment I; Treatment III, chicken manure at 0.5 ton/ha; and Treatment IV, MASA (processed from agricultural and industrial wastes) fertilizer at 0.5 ton/ha. All treatments were applied once in every 2 weeks. No significant difference (P > 0.05) existed in the harvest and production of milkfish among the treatments. However, economic indicators such as return-on-investment (ROI), payback period, and marginal analysis ranked the performance of the fertilizer treatments in the order of I, II, III and IV. Fish kills occurred in three ponds applied with chicken manure and MASA fertilizer. This could have been due to a heavy build-up of organic matter in the pond bottom which led to the collapse of the benthic algal community, depletion of dissolved oxygen and the presence of hydrogen sulfide. It is therefore suggested that a lower dosage of organic fertilizer should be applied in ponds especially during the rainy season

Performance of recirculating systems for prawn hatchery and broodstock maturation tanks

The potential use of recirculating systems with facilities for waste removal for prawn (Penaeus monodon) hatchery and broodstock maturation tanks was investigated. Recirculating systems evaluated for larval culture tanks were biological filtration and zigzag stream sedimentation. Systems using airlift and airstones as aeration devices with partial water change but with no provision for recirculation served as control. Results showed successful rearing of Penaeus monodon (nauplii-postlarvae) in systems with facilities for wastewater recirculation. Aeration systems became ineffective in maintaining acceptable water quality as shown by increases in 5-day biochemical oxygen demand (BOD5), ammonia (NH4-N) and nitrite (NO2-N) nitrogen, and decreases in dissolved oxygen (DO). For broodstock maturation, a recirculating system with a preconditioned biological filter was compared with a flow-through system. Biological filtration proved to be useful in meeting water quality requirements. Nitrification was satisfactory with ammonia levels lower than 1·0 mg liter−1. The pH values in the biofilter effluent were maintained at 7·8–8·3. BOD5 levels were below 10 mg liter−1 while DO tended to drop due to the nitrifying activity of the filter. Better reproductive performance of Penaeus monodon broodstock was obtained in the recirculating system than in the flow-through system

The macronutrient composition of natural food organisms mass cultured as larval feed for fish and prawns

The macronutrient composition of natural food organisms that are mass cultured as feed for the larval stages of fish and prawns in the SEAFDEC Aquaculture Department was determined by chemical analysis. The food organisms included five species of marine phytoplanktons (algae): Chaetoceros calcitrans, Skeletonema costatum, Tetraselmis chui, Chlorella vulgaris and Isochrysis galbana, and two zooplanktons: Artemia sp. nauplii (San Francisco Bay strain) and Brachionus plicatilis. The algal species were grown in batches on Guillard and Ryther media and harvested during the exponential phase of growth using a procedure which preserved cellular integrity and prevented cell lysis. The zooplankton were cultured using standard techniques adopted at the SEAFDEC Larval Food Laboratory. Each species was analyzed for proximate composition (protein, fat, fiber and ash) and for mineral content (calcium and phosphorous). Nitrogen-free extract (NFE) was determined by difference. For the five algal species, the protein, fat and NFE contents varied from 22% to 48%, 2% to 16% and 14% to 24%, respectively. The zooplanktons had higher protein and fat contents than any of the phytoplankton species except I. galbana which had the highest fat content. On the other hand, the phytoplanktons, particularly the diatoms which have a siliceous cell wall, contained significantly higher quantities of inorganic matter (ash). C. vulgaris had the highest fiber content which may be attributed to its cellulosic cell wall

Ion chromatography of nitrite, bromide and nitrate ions in brine samples using a chloride-form anion-exchange resin column

In aquaculture research, maintenance of water culture quality is of great importance. Recent improvement in fishpond management and fish culture systems, such as intensive feeding and fertilization, have created complex problems. Deterrioration of weter quality is primarily the resulting effect of these improvements. Foe example, high-protein feeds and nitrogen fertilizers applied in fishponds produce considerable amount of nitrate in the water. Moreover, their synergistic effects cannot be ignored. Hence the routine determination of nitrite in fishpond water is required. Since its introduction by Small et al., ion chromatography has been widely used for the determination of ions in water. However,the presence of very high concentrations of chloride is the main obstacles in the analysis of seawater samples, affecting the separation and detection not only of nitrite but also of other anions. Itoh and Shinbori applied ion chromatography to the analysis of seawater using a 125-cm long column and a conductimetric detector. This technique provided by a simple and sensitive analysial method for brine samples. However, nitrite could not be determined owing to the presence of a large chloride peak. Attempts to determine nitrite in seawater also led to innovations in the methodology. Lee and Field employeed a post-column cerium flourescence detection system to determine nitrite and nitrite in drinking water and seawater. The use of a pretreatment column in the silver form for removal of chloride has been reported. Various detectors have been applied in ion chromatography in addition to the conductimetric detector. The UV detector has been shown to be luseful detector for several kinds of inorganic anions. Selected detection of specified inorganic ions can be achieved by tuning the wavelength of the UV detector in ion chromatography and also in ion-exclusion chromatography. The elemination of the chloride matrix interference in the sub-ppm determination of nitrite in seawater was achieved by a heart-cutting and recycling method using a dual detection system consisting of conductimetric and UV detectors. This method, however, requires valve switching during analysis and needs a long analysis time. This paper describes a simple and rapid method of UV-absorbing anions, such as nitrite, nitrite and bromide, in brine samples using a chloride-form anion-exchange resin column combined with a UV detector