Now showing items 1-7 of 7

    • Article

      Accumulation and excretion of metal granules in the prawn, Penaeus monodon, exposed to water-borne copper, lead, iron and calcium 

      G Vogt & ET Quinitio - Aquatic Toxicology, 1994 - Elsevier
      Juveniles of the giant tiger prawn, Penaeus monodon, were exposed for 10 days to 1 mg/l copper, lead, iron or calcium in order to investigate the formation and accumulation of metal granules in major soft tissues as well as their excretion from the body. Metal deposition was investigated by histochemistry and electron microscopy in the hepatopancreas and surrounding organs and tissues like the stomach, midgut, anterior midgut caecum, thoracal antennal gland extensions, haematopoietic tissue, and interspersed musculature, connective tissue and pigment tissue. The abundance of metal granules varied greatly between the metals and the tissues. Iron and calcium deposits were found in none of the tissues investigated. Copper granules were accumulated in high quantity in the hepatopancreas tubules, were scarce in the antechamber of the hepatopancreas, the anterior midgut and the anterior midgut caecum, and were lacking in the other tissues. The amount and size of copper granules increased along the hepatopancreas tubules in accordance with the cells' age. The granules were released by discharge of senescent hepatopancreas cells in the antechamber region and were added to the faeces. Lead granules were primarily found in the thoracal extensions of the antennal gland. In the hepatopancreas they occurred only in very small quantities, and in the other organs and tissues they were absent. In the antennal gland, the lead granules were individually discharged into the gland lumen by apocrine secretion and excreted with the urine. The observed ability of Penaeus monodon to detoxify and remove metals like copper and lead by granule formation and excretion and to prevent other metals like iron from entrance into major soft tissues corroborate that decapods are no suitable organisms for a long-term biomonitoring of heavy metal pollution.
    • Article

      Effect of salinity on hemolymph calcium concentration during the molt cycle of the prawn Penaeus monodon 

      FD Parado-Estepa, JM Ladja, EG de Jesus & RP Ferraris - Marine Biology, 1989 - Springer Verlag
      Prawns (Penaeus monodon) were obtained from ponds in Iloilo, Philippines, in 1984 and 1985 and maintained in salinities from 8 to 44‰. Total hemolymph calcium was largely affected by molt stage and less so by salinity. A sharp, transient increase in hemolymph calcium occurred 3 to 6 h postmolt, followed by an equally rapid decrease from 6 h postmolt to intermolt. This biphasis response was limited to prawns in 8, 20 and 32‰S; in 44‰S, hemolymph calcium remained the same throughout the sampling period. Peak concentrations of total calcium were greater in low (8 and 20‰S) than in high salinities. Salinity had no effect on the duration of molt cycle nor on time of occurrence of molt. Almost half of molting incidents occurred between 18.01 and 0.00 hrs, and one-third between 0.01 and 06.00 hrs.
    • Article

      Effect of salinity on the osmotic, chloride, total protein and calcium concentrations in the hemolymph of the prawn Peneaus monodon (Fabricius) 

      RP Ferraris, FD Parado-Estepa, JM Ladja & EG de Jesus - Comparative Biochemistry and Physiology - Part A: Physiology, 1986 - Elsevier
      1. Osmolality and chloride concentrations in the hemolymph of Penaeus monodon became stable 1 day after molting in 32 ppt, while total protein and calcium concentrations remained stable throughout the molting cycle. When intermolt (≥ 36 hr postmolt) animals were transferred from control (32 ppt) to experimental (8–40 ppt) salinities, osmolality, chloride and total protein, but not calcium, concentrations in the hemolymph achieved steady state values 24–48 hr after transfer.

      2. The hemolymph osmolality was a linear function (slope = 0.28) of medium osmolality at salinities between 8 and 40 ppt. It was isosmotic to seawater at 698 mOsm (10 g prawns) and 752 mOsm (30 g), and was hyperosmotic to the medium below isosmotic concentrations, and hypoosmotic to those above.

      3. Hemolymph chloride concentration was isoionic to seawater at 334 mM, and was hyperregulated below isoionic concentrations, and hyporegulated to those above.

      4. P. monodon maintained its hemolymph calcium concentration between 6.4 and 10 mM when medium salinities increased from 8 to 40 ppt.

      5. Total protein concentration in the hemolymph was independent of medium salinity (8–40 ppt) and hemolymph osmolality (540–850 mOsm).
    • Book chapter

      The essential nutrients: Minerals 

      OM Millamena - In OM Millamena, RM Coloso & FP Pascual (Eds.), Nutrition in Tropical Aquaculture: Essentials of fish nutrition, feeds, and feeding of tropical aquatic species, 2002 - Aquaculture Department, Southeast Asian Fisheries Development Center
      This section discusses the macro, micro, and trace minerals; their physiologic functions; and deficiency signs and symptoms. It also gives a summary of the mineral functions and mineral requirements of fishes and shrimp.
    • Article

      Histopathology of the chronic soft-shell syndrome in the tiger prawn Penaeus monodon 

      MCL Baticados, RM Coloso & RC Duremdez - Diseases of Aquatic Organisms, 1987 - Inter Research
      One of the disease problems that affect the production of tiger prawn Penaeus monodon Fabricius in brackish-water ponds is the chronic soft-shell syndrome, a condition in which the prawn shell is persistently soft for several weeks. To determine the extent of damage in affected prawns, the histopathology of this syndrome was studied using light microscopy, transmission and scanning electron microscopy, and histochemical determination of calcium. Light microscopic studies of the exoskeleton of soft and normal hard-shelled prawns showed several distinct layers: an outer epicuticle, a thick exocuticle and a thinner endocuticle overlying the epidermis. The cuticular laters of the soft shell oftern had a rough or wrinkled surface and were usually disrupted and separated from the epidermis while those of the hard shell were generally intact and attached to the epidermis. The exocuticle and endocuticle of the hard shell were considerably thicker than those of the soft shell. Ultrastructural observations revealed the presence of a very thin membranous later under the endocuticle. Tegumental ducts and pore canals traversed the 4 cuticular layers and were distinctly observed as pore openings on the epicuticle surface. The epicuticle had a bilaminar and non-lamellate structure. The exocuticle had more widely-spaced lamellae consisting of fibers arranged in a more compact pattern than in the endocuticle. Histochemical determination of calcium was done in exoskeleton and hepatopancreas of soft- and hard-shelled prawns. The hepatopancreas of soft-shelled prawn stained more intensely for calcium than that of the hard-shelled one. There was no great difference in calcium content of hard and soft shell, although the former stained slightly more intensely. Histopathological changes in the hepatopancreas of soft-shelled prawns were also observed.
    • Article

      Interaction between dietary levels of calcium and phosphorus on growth of juvenile shrimp, Penaeus monodon 

      VD Peñaflorida - Aquaculture, 1999 - Elsevier
      Information on the dietary phosphorus (P) requirement is essential in the formulation of a cost-effective and low-pollutant feed. Ten isonitrogenous (40% CP) casein–gelatin-based diets containing five graded levels of P (0, 0.5, 1, 1.5, 2%) for each of two levels of calcium (Ca) (0, 1.5%) were fed to juvenile Penaeus monodon previously fed a basal diet containing no P and Ca for 15 days. After 90 days, survival ranged from 70% to 87% but was not significantly different (P<0.05) among treatments. A significant Ca and P interaction was obtained in percent weight gain. Shrimp fed with diet containing 0.5% supplemental P (0.74% total P) without Ca supplementation showed a significantly higher weight gain. For total biomass of shrimp, analysis of variance showed no significant interaction between Ca and P level, but significant differences were obtained among P levels when averaged over two Ca levels. The graded levels of P did not affect shrimp whole body P (1.07–1.13%). Whole body P was not a good index in determining the P requirement of P. monodon. In the absence of Ca, 0.5% supplemental P (0.74% total P) provided maximum growth of P. monodon postlarvae. The level of Ca should be reduced in formulating diets to minimize supplemental P, thereby effecting savings in feed cost and less loss of P to the water system.
    • Conference paper

      Mineral requirements of Penaeids 

      F Piedad-Pascual - In Advances in Tropical Aquaculture: Workshop at Tahiti, French Polynesia, February 20 - March 4, 1989, 1990 - Institut Francais de Recherche pour l'Exploitation de la Mer
      Series: Actes de Colloque 9
      Marine shrimps absorb minerals from their aquatic environment aside from the minerals that come from the food they eat. Thus, the dietary requirement of shrimps for certain minerals will depend on the amounts and availability of these minerals in the aquatic environment. Dietary sources for growth may be necessary due to losses during moltings.

      Most of the dietary studies for mineral requirements have been done under laboratory conditions with purified or semi-purified diets and hardly any information is available under practical culture conditions. Most published data for mineral requirements are for juvenile Penaeus japonicus. There are few data for P. monodon, P. californiensis, P. merguiensis, P. aztecus.

      Calcium and phosphorus are the minerals that have been studied the most. These two have been found to be related to problems of soft-shelling in P. monodon. Apparently calcium and phosphorus requirements are within the range of 1 to 2%. The ratio of calcium to phosphorus in the diet is also an important factor in the efficient utilization of both minerals. It seems that a 1 :1 ratio provides for good growth. Phosphorus deficiency results in reduced growth while lack of magnesium brings about decreased growth, poor survival and reduced feed efficiency in P. japonicus. Iron toxicity has also been observed in P. japonicus.

      It might not be necessary to include some minerals in the diet of penaeids.