Salt and Water Balance in Salmon Smolts

1970 ◽  
Vol 52 (3) ◽  
pp. 553-564
Author(s):  
W. T. W. POTTS ◽  
MARGARET A. FOSTER ◽  
J. W. STATHER
Keyword(s):  
Water Balance ◽  
Fresh Water ◽  
Sodium Pump ◽  
Sea Water ◽  
High Rate ◽  
Exchange Diffusion ◽  
Rapid Changes ◽  
Alternative Hypotheses ◽  
Salt And Water Balance

1. Salmon smolts adapted to sea water maintain a high rate of turnover of both sodium and chloride, but when adapted to fresh water the rate of turnover is low. 2. Only a small part of the influx takes place through the gut. 3. On immediate transfer from sea water to dilute sea water or to fresh water the influxes decline rapidly, but on transfer from fresh water to sea water the restoration of the fluxes takes place slowly. 4. The alternative hypotheses that the rapid changes are due to exchange diffusion or to rapid adjustments of the sodium pump are discussed.

scholarly journals Salt and Water Balance in the East African Fresh-Water Crab, Potamon Niloticus (M. Edw.)

1959 ◽  
Vol 36 (1) ◽  
pp. 157-176 ◽  
Author(s):  
J. SHAW
Keyword(s):  
Water Balance ◽  
Fresh Water ◽  
Sea Water ◽  
Freezing Point ◽  
Salt Content ◽  
The Body ◽  
Sodium Balance ◽  
East African ◽  
Sodium Loss ◽  
Salt And Water Balance

1. The mechanisms of salt and water balance in the East African fresh-water crab, Potamon niloticus, have been investigated. 2. The freezing-point depression of the blood is equivalent to that of a 271 mM./l. NaCl solution. 3. The animals cannot survive in solutions more concentrated than 75% sea water. Above the normal blood concentration, the blood osmotic pressure follows that of the medium. 4. The urine is iso-osmotic with the blood and is produced at a very slow rate. The potassium content is only half that of the blood. 5. The animal loses sodium at a rate of 8 µM./10 g./hr. mainly through the body surface. Potassium loss occurs at one-sixteenth of this rate. 6. Sodium balance can be maintained at a minimum external concentration of 0.05 mM./l. Potassium requires a concentration of 0.07 mM./l. 7. Active absorption of both sodium and potassium occurs. The rate of uptake of sodium depends on the extent of previous sodium loss. The rate of sodium uptake may be affected by such environmental factors as the salt content of the water, temperature and oxygen tension. 8. The normal oxygen consumption rate is 0.72 mg./10 g./hr. A minimum of 2.3% is used in doing osmotic work to maintain salt balance. 9. The salt and water balance in Potamon is discussed in relation to the adaptation of the Crustacea to fresh water. The importance of permeability changes is stressed.

Salt and Water Balance of the Spiny Lobster, Panulirus Argus: The Role of the Antennal Glands

1977 ◽  
Vol 70 (1) ◽  
pp. 221-230
Author(s):  
D. F. MALLEY
Keyword(s):  
Water Balance ◽  
Sea Water ◽  
Spiny Lobster ◽  
Water Levels ◽  
Panulirus Argus ◽  
Antennal Glands ◽  
Salt And Water Balance

1. Panulirus argus in full sea water differs from most other marine isosmotic decapods by regulating Cl− levels in the haemolymph slightly below those in sea water and by having haemolymph K+ levels similar to those in sea water. The species is typical in regulating haemolymph Na+ and Ca2+ above, and Mg2+ and SO42- below, sea-water levels of these ions. Its haemolymph Mg2+ and SO42- concentrations are amongst the lowest reported in marine decapods. 2. The antennal glands contribute to this regulation of Mg2+ SO42- and Cl− by producing urine with markedly, and approximately equally, elevated Mg2+ and SO42- levels, and slightly elevated Cl− levels, compared with those in the haemolymph. The antennal glands show a small tendency to conserve water. Note: Freshwater Institute, 501 University Crescent, Winnipeg, Manitoba, Canada R3T 2N6.

Studies on Salt and Water Balance in Caddis Larvae (Trichoptera)

1961 ◽  
Vol 38 (3) ◽  
pp. 501-519 ◽  
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Water Balance ◽  
Sea Water ◽  
Salt Water ◽  
Chloride Concentration ◽  
Malpighian Tubule ◽  
Free Water ◽  
The Body ◽  
Chloride Uptake ◽  
Concentrated Solution ◽  
Salt And Water Balance

1. Limnephilus affinis larvae tolerate external salt concentrations up to at least 410 mM./l. NaCl (about 75% sea water) and survive for short periods in 470 mM./l. NaCl (about 85/ sea water). 2. The body wall is highly permeable to water, but relatively impermeable to sodium and chloride. Most of the sodium and chloride uptake from salt water occurs via the mouth. 3. The sodium and chloride levels in the haemolymph are powerfully regulated. Both are maintained strongly hypotonic against large external concentration gradients. 4. The Malpighian tubule-rectal system is very sensitive to changes in the haemolymph chloride level. The chloride concentration in the rectal fluid can be at least three times greater than the concentration in the haemolymph, and slightly greater than the concentration in the external medium. 5. The rectal fluid is hyper-osmotic to the haemolymph and to the medium at high external salt concentrations. 6. At external concentrations greater than about 200 mM./l. NaCl, water balance is maintained by regulating the haemolymph roughly iso-osmotic with the medium. This is partly achieved by increasing the non-electrolyte fraction in the haemolymph. A small quantity of osmotically free water is available to replace any osmotic loss. This can be obtained by drinking salt water and producing a concentrated solution of salts in the rectum.

Salt and water balance of modern baleen whales: rate of urine production and food intake

2003 ◽  
Vol 81 (4) ◽  
pp. 606-616 ◽  
Author(s):  
M Kjeld
Keyword(s):  
Water Balance ◽  
Creatinine Clearance ◽  
Fresh Water ◽  
Marine Mammals ◽  
Control Mechanisms ◽  
Creatinine Concentration ◽  
Baleen Whales ◽  
Terrestrial Mammals ◽  
Urine Production ◽  
Salt And Water Balance

Whales, as pelagic marine mammals, are thought to have evolved from fresh-water-dependent terrestrial mammals. Baleen whales feed primarily on salty euphausiids (krill) and have no access to fresh water. How have these mammals adapted to lifelong habitation in a hyperosmotic medium? A new approach is proposed for studying this by using allometry (scaling) of endogenous creatinine clearance in mammals together with determinations of creatinine concentration in fresh postmortem blood and urine of fin whales (Balaenoptera physalus) and sei whales (Balaenoptera borealis). From the predicted mean creatinine-clearance values and the measured mean creatinine concentrations, a urine-production rates of 974 and 627 L/day for the fin and sei whales, respectively, were computed. Average daily krill ingestion of about 1300 and 835 L is predicted for the fin and sei whales, respectively. The whales seem to ingest about 30% more than earlier reported of a prey, which has about 50% of the salt concentration of seawater, thus maintaining the salt and water balance with a minimum of 1–2% seawater ingestion. The method used to estimate the above volumes could be a valuable tool in further studies of the water and salt balance of the large baleen whales, which may not have the same osmoregulatory control mechanisms as the smaller Odontoceti.

scholarly journals Sodium and Water Balance in the Cichlid Teleost, Tilapia Mossambica

1967 ◽  
Vol 47 (3) ◽  
pp. 461-470 ◽  
Author(s):  
W. T. W. POTTS ◽  
M. A. FOSTER ◽  
P. P. RUDY ◽  
G. PARRY HOWELLS
Keyword(s):  
Water Balance ◽  
Fresh Water ◽  
Sea Water ◽  
Tritiated Water ◽  
Sodium Influx ◽  
Water Drinking ◽  
Body Sodium ◽  
Total Body ◽  
Sodium And Water Balance ◽  
Total Sodium

1. The total body sodium increases from 45.9 µM/g. fish in fresh water to 59.9 µM/g. fish in 200 % sea water. 2. The rate of exchange of sodium increases from 2 µM/g./hr. in fresh water to 60 µM/g./hr. in 100% sea water. 3. The rate of drinking increases from 0.26%/hr. fresh water to 1.6%/hr. in 400% sea water. Even in 200% sea water drinking accounts for only a quarter of the total sodium influx. 4. The permeability to water, as measured by tritiated water, is highest in fresh water and lowest in 200% sea water. The permeabilities to water measured in this way are consistent with the drinking rates determined in sea water and 200% sea water.

Studies on Salt and Water Balance in Myxine Glutinosa (L.)

1965 ◽  
Vol 42 (2) ◽  
pp. 359-371
Author(s):  
R. MORRIS
Keyword(s):  
Water Balance ◽  
Sea Water ◽  
External Medium ◽  
Freezing Point ◽  
Freezing Point Depression ◽  
High Concentration ◽  
After Effects ◽  
Monovalent Ions ◽  
Calcium Magnesium ◽  
Salt And Water Balance

1. Measurements of freezing-point depression and chemical analysis have been made of the plasma and urine of Myxine. 2. The plasma is generally slightly hypertonic to sea water whilst the urine tends to be slightly hypotonic to the blood. 3. The urinary output is low (5·4±1·6 ml./kg./day) and the majority of animals do not swallow sea water. 4. Analyses of plasma and urine indicate that the kidney participates in ionic regulation by reducing the concentrations of calcium, magnesium and sulphate in the plasma relative to sea water. Chloride seems to be conserved whilst potassium may be conserved or excreted. The high concentration of magnesium in the plasma of animals kept in static sea water may be caused by the after effects of urethane. These animals continue to excrete magnesium at normal rates. 5. The rates at which calcium, magnesium and sulphate enter an animal which does not swallow sea water are proportional to the diffusion gradients which exist between the external medium and the plasma. The situation is more complicated for monovalent ions, but there is no evidence of specialized ion-transporting cells within the gill epithelium. 6. In those animals which swallow sea water the amounts of ions absorbed from the gut are very large compared with the renal output and it would therefore seem unlikely that swallowing is part of the normal mechanism of salt and water balance. 7. It is argued that the mechanism of salt and water balance in Myxine is likely to be primitive and that the vertebrate glomerulus was probably developed originally in sea water as an ion-regulating device.

scholarly journals Investigation into Groundwater Resources in Southern Part of the Red River’s Delta Plain, Vietnam by the Use of Isotopic Techniques

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2120 ◽  
Author(s):  
Van Lam ◽  
Van Hoan ◽  
Duc Nhan
Keyword(s):  
Water Resources ◽  
Fresh Water ◽  
Sea Water ◽  
Saline Water ◽  
Groundwater Resources ◽  
High Rate ◽  
14C Dating ◽  
Study Region ◽  
Delta Plain ◽  
Pleistocene Aquifer

Groundwater in the Red River’s delta plain, North Vietnam, was found in Holocene, Pleistocene, Neogene and Triassic aquifers in fresh, brackish and saline types with a total dissolved solids (TDS) content ranging from less than 1 g L−1 to higher than 3 g L−1. Saline water exists inHolocene aquifer, but fresh and brackish water exist in Pleistocene, Neogene and Triassic aquifers. This study aims at the investigation into genesis and processes controlling quality of water resources in the region. For this isotopic, combined with geochemical techniques were applied. The techniques include: (i) measurement of water’s isotopic compositions (δ2H, δ18O) in water; (ii) determination of water’s age by the 3H- and 14C-dating method, and (iii) chemical analyses for main cations and anions in water. Results obtained revealed that saline water in Holocene aquifer was affected by seawater intrusion, fresh water in deeper aquifers originated from meteoric water but with old ages, up to 10,000–14,000 yr. The recharge area of fresh water is from the northwest highland at an altitude of 140–160m above sea level. The recharge water flows northwesterly towards southeasterly to the seacoast at a rate of 2.5m y−1. Chemistry of water resources in the study region is controlled by ferric, sulfate and nitrate reduction with organic matters as well as dissolution of inorganic carbonate minerals present in the sediment deposits. Results of isotopic signatures in water from Neogene, Triassic and Pleistocene aquifers suggested the three aquifers are connected to each other due to the existence of faults and fissures in Mesozoic basement across the delta region in combination with high rate of groundwater mining. Moreover, the high rate of freshwater abstraction from Pleistocene aquifer currently causes sea water to flow backwards to production well field located in the center of the region.

Effects of rapid changes in salinity on the renal function of a euryhaline teleost

1965 ◽  
Vol 209 (5) ◽  
pp. 1025-1030 ◽  
Author(s):  
Warren R. Fleming ◽  
Jon G. Stanley
Keyword(s):  
Renal Function ◽  
Glomerular Filtration ◽  
Fresh Water ◽  
Sea Water ◽  
Tubular Reabsorption ◽  
Urine Flow ◽  
Estimated Gfr ◽  
Rapid Changes ◽  
Euryhaline Teleost ◽  
Urine And Serum

Techniques developed to study renal function of the euryhaline teleost, Fundulus kansae, are described. Effects of a sudden transfer from fresh water to sea water on urine flow and urine and serum osmotic pressures were studied. Glomerular filtration rates (GFR) of animals adapted to fresh water and to sea water for 7 days were estimated. Urine flow was found to be a function of size and of handling, as well as of salinity. Animals held in fresh water showed an initial diuresis which reached a peak approximately 2 hr after cannulation. Urine flow thereafter was in the range of 200 ml/kg per day for fish weighing 1.58 ± 0.3 g, and the estimated GFR was 600 ml/kg per day. Animals held in sea water had urine flows ranging from 5 to 20 ml/kg per day, and filtration rates ranging from 20 to 45 ml/kg per day were estimated. The urine collected from the 2nd to approximately the 10th day after a sudden transfer into sea water was hypertonic to the serum. It is concluded that both a reduction in GFR and an increase in the tubular reabsorption of water are elements of renal function utilized when this animal moves from a hypotonic to a hypertonic environment.

The Water Balance of a Serpulid Polychaete, Mercierella Enigmatica (Fauvel)

1974 ◽  
Vol 60 (2) ◽  
pp. 331-338
Author(s):  
HELEN LE B. SKAER
Keyword(s):  
Water Balance ◽  
Fresh Water ◽  
Sea Water ◽  
External Medium ◽  
Inorganic Ions ◽  
Sodium Calcium

1. Mercierella enigmatica, a serpulid polychaete, lives in water ranging in concentration from fresh water to 150% sea water (< 1-55‰). 2. The concentrations of five inorganic ions (Na+, K+, Ca2+, Mg2+ and Cl-2) in the blood have been measured both during and after equilibration of the animals with media of altered salinity. 3. The concentrations of calcium and potassium have also been measured in filtrates of the blood from animals equilibrated in three media of differing salinity. 4. Concentrations of all the ions measured vary linearly with the concentration of the external medium. The levels of sodium, calcium (in filtered blood) and chloride are near the isionic line, while those of magnesium and potassium (even in filtered blood) are slightly higher in the blood over the whole range.

Distribution of dry matter between the tissues and coelom in Arenicola marina (L.) equilibrated to diluted sea water

1977 ◽  
Vol 57 (1) ◽  
pp. 97-107 ◽  
Author(s):  
R. F. H. Freeman ◽  
T. J. Shuttleworth
Keyword(s):  
Water Balance ◽  
Water Content ◽  
Dry Matter ◽  
Sea Water ◽  
External Medium ◽  
Comprehensive Review ◽  
Arenicola Marina ◽  
Wide Range ◽  
Salt And Water Balance

The observations of Schlieper (1929) established the lugworm Arenicola marina (L.) as an osmoconformer which remains virtually isosmotic with the external medium over a wide range of salinities. In a recent comprehensive review of salt and water balance in lugworms, Oglesby (1973) describes ‘the extensive swelling associated with transfer of lugworms to lower salinities’, and ‘when maintained in salinities lower than about 50% s.w. in the laboratory, lugworms are rendered incapable of such vital physiological activities as burrowing and burrow ventilation’. Under these conditions, lugworms exhibit little or no ability to regulate their volume or water content.

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