scholarly journals Oxygen Consumption as a Function of Size and Salinity in Metapenaeus monoceros Fab. From Marine and Brackish-Water Environments

1958 ◽  
Vol 35 (2) ◽  
pp. 307-313
Author(s):  
KANDULA PAMPAPATHI RAO

1. The oxygen consumption in relation to the salinity of the medium has been studied in a marine and a brackish-water population of the prawn, Metapenaeus monoceros Fab. 2. It has been shown that the regression coefficient of oxygen consumption against weight is not the same for media of different salinity and for the two populations. 3. In both the groups of prawns an increase in the oxygen consumption was observed, with a decrease in the salinity of the medium below that of the habitat. But the marine prawns showed higher rates in 50 and 25% sea water compared to the brackish-water prawns. On the other hand, the brackish-water prawns exhibited a higher rate of oxygen consumption in 100% sea water and in tap water. 4. It is suggested that these differences might be due to (i) an osmotic adaptation, and (ii) the operation of a metabolic homoeostatic mechanism in relation to osmotic regulation.

1935 ◽  
Vol 12 (3) ◽  
pp. 217-221
Author(s):  
OTTO LÖWENSTEIN

1. The rate of oxygen uptake was studied in the brackish water amphipod Gammarus chevreuxi in water of different salinities (25 per cent, sea water and sea water). The respiratory rate was found to be approximately 20 per cent, lower in sea water than in 25 per cent, sea water which is a concentration occurring in the natural habitat. Anaesthetised animals showed the same percentage decrease as unanaesthetised animals. 2. The change in oxygen consumption takes place immediately after the transfer and remains constant thereafter. It is completely reversible. 3. A comparison with the unanaesthetised respiratory rates of the related freshwater species G. pulex and marine G. marinus shows that the rate of oxygen consumption of the brackish water form G. chevreuxi in 25 per cent, sea water lies between the two others.


Author(s):  
Sandra E. Shumway

Specimens of Pagurus bernhardus (with and without shells) were exposed to both gradual (sinusoidal) and abrupt (square-wave) salinity fluctuations and changes in haemolymph osmolality, tissue water content and oxygen consumption monitored. Oxygen consumption was also monitored under steady-state conditions; under these conditions there was no significant difference between the rate of oxygen consumption by animals with shells and animals without shells. Oxygen consumption was found to vary with body weight according to the equation O2 consumption = 0·292 W0·668. During exposure to fluctuating salinities the crabs with shells were seen to increase loco-motory activity when the external medium declined to approximately 75% sea water. Haemolymph osmolality values followed the same pattern of change as the external medium; the haemolymph of crabs without shells became significantly more dilute during exposure to low salinity than did that of crabs with shells. P. bernhardus showed significant increases and decreases in hydration level as salinities fell and rose respectively. Crabs with shells showed a marked temporary increase in oxygen consumption when the external medium declined to approximately 75% sea water; crabs without shells showed no such response. The importance of the shell as a means of protection against dilute media is discussed.


1973 ◽  
Vol 59 (1) ◽  
pp. 267-274
Author(s):  
H. J. ATKINSON

1. The rate of oxygen consumption of individual male Enoplus brevis and E. communis was measured at 15 °C, after altering the oxygen regime experienced since the animals were collected. 2. When both E. brevis and E. communis were transferred to 35 Torr from atmospheric oxygen tensions, their oxygen consumption was only two-thirds of that of individuals maintained at this lower oxygen tension. 3. The rate of oxygen consumption of the two species at 135 Torr was unaltered by exposure for 2 h to oxygen-free sea water. 4. The results are discussed in relation to the overall influence of fluctuating oxygen regimes on the oxygen requirements of nematodes.


1980 ◽  
Vol 60 (4) ◽  
pp. 1043-1051 ◽  
Author(s):  
P. Milton ◽  
R. N. Dixon

The oxygen consumption of the intertidal teleost Blennius pholis L. has been investigated during and subsequent to quinaldine anaesthesia, using a continuous flow apparatus. Marked reductions in oxygen consumption were noted in high concentrations of quinaldine (10 and 20 ppm), and both entry into anaesthesia and recovery from it were rapid. A period of enhanced oxygen consumption followed anaesthesia, except in the lowest concentration of quinaldine (1 ppm). Experiments conducted over a 4 h period with three different salinities (100%, 30% and 10 % sea water) indicated that, under the influence of 10 and 20 ppm quinaldine solutions, the fish more resembled an osmoconformer than an osmoregulator. During anaesthesia, water was lost osmotically in 100% sea water, and gained in the more dilute salinities, although it was possible that some osmotic regulation continued. Physiological measurements indicated that quinaldine is suitable for the capture and marking of fish; for surgical procedures it should be mixed with another anaesthetic, for example MS-222, due to the retention of a response to vibratory stimuli.


1930 ◽  
Vol 7 (1) ◽  
pp. 41-48
Author(s):  
G. S. CARTER

1. In the presence of thyroxine in concentrations of 1/45,000 to 1/75,000 the initial rate of oxygen consumption of the spermatozoa of Echinus miliaris is the same as in sea-water without the drug, but this rate of oxygen consumption is prolonged for a longer time in the presence of the drug. The rate of oxygen consumption in the presence of the drug falls after this period, and at the end of 2-4 hours is approximately equal to that in clean sea-water. 2. In a concentration of 1/30,000 the drug is toxic, and of 1/100,000 the effect is incomplete. 3. These effects are parallel to, and apparently of the same nature as, the effects of secretions of the eggs of the same species upon the oxygen consumption; but the effects of the egg secretions are much greater in extent. 4. The suggestion is made that the egg secretions contain, in addition to their other known constituents, either a body of which the physiological effect is similar to that of thyroxine, and which is perhaps similar to it in chemical structure, or some constituent from which such a body is built, when it is absorbed by the spermatozoon. 5. In its action upon the spermatozoon the effect of thyroxine is to remove or reduce the cause of the decreasing activity of the spermatozoon in sea-water (as revealed by its oxygen consumption). This effect is immediate and may take place at any period during the life of the spermatozoon at which its oxygen consumption in the presence of thyroxine is greater than that in sea-water.


1973 ◽  
Vol 30 (12) ◽  
pp. 1898-1900 ◽  
Author(s):  
Kathryn G. Withey ◽  
Richard L. Saunders

Postsmolt Atlantic salmon (Salmo salar) subjected to a reciprocal photoperiod regime (decreasing daylength from early March and increasing daylength from late June) had significantly lower standard rates of oxygen consumption than those subjected to a simulated natural photoperiod regime when both were tested in total darkness in sea water in late summer. A reduced metabolic level, as indicated by the low standard rate of oxygen consumption, in the test fish is consistent with earlier observations of reduced feeding and growth rates and food conversion efficiencies in similarly treated fish following transfer to sea water.


Author(s):  
Raveesha P ◽  
K. E. Prakash ◽  
B. T. Suresh Babu

The salt water mixes with fresh water and forms brackish water. The brackish water contains some quantity of salt, but not equal to sea water. Salinity determines the geographic distribution of the number of marshes found in estuary. Hence salinity is a very important environmental factor in estuary system. Sand is one major natural aggregate, required in construction industry mainly for the manufacture of concrete. The availability of good river sand is reduced due to salinity. The quality of sand available from estuarine regions is adversely affected due to this reason. It is the responsibility of engineers to check the quality of sand and its strength parameters before using it for any construction purpose. Presence of salt content in natural aggregates or manufactured aggregates is the cause for corrosion in steel. In this study the amount of salinity present in estuary sand was determined. Three different methods were used to determine the salinity in different seasonal variations. The sand sample collected nearer to the sea was found to be high in salinity in all methods.  It can be concluded that care should be taken before we use estuary sand as a construction material due to the presence of salinity.


1998 ◽  
Vol 76 (7) ◽  
pp. 1188-1197 ◽  
Author(s):  
Heli M. Jutila b. Erkkilä

Seed banks of two seashore meadows were studied on the west coast of Finland (latitude 61°30'-61°33'N, longitude 21°28'-21°41'E). Samples were taken in June to a depth of 10 cm in the geolittoral zone of the grazed and ungrazed transects. The grazed samples were halved lengthwise: one half was grown immediately, the other after cold treatment. One third of the all samples was treated as controls, one third was watered with brackish water, and one third was given a pesticide treatment. Altogether, 13 926 seedlings germinated and 25 species were identified (three annuals, two biennials, and the rest perennials). Most seedlings were perennial monocots, with Juncus gerardii Loisel. the most abundant species. The seed bank was significantly larger and richer in the ungrazed site than in the grazed site. Cold treatment reduced the number of germinating species and seedlings. In the grazed and non-cold-treated samples, the numbers of species and seedlings were highest in the pesticide treatment. In ungrazed samples there were no significant differences among treatments. After the cold treatment, the least number of species and seedlings was produced by the salt-water treatment. Changing brackish water to tap water led to a burst of germination, especially of J. gerardii. The seed bank of the upper geolittoral zone was richer than that of the middle geolittoral. The multivariate classification and ordination groupings are based on the abundances of J. gerardii and Glaux maritima L.; different treatments were not distinguishable. There was a low resemblance between the seed bank and the aboveground vegetation.Key words: seed bank, salinity, pesticide, seashore meadow, cold treatment, vegetation.


In a comparison of muscles poisoned with mono-iodo-acetic acid (IAA) in the presence and in the absence of oxygen respectively, Lundsgaard (1930) found:- (1) That the spontaneous breakdown of phosphagen in poisoned resting muscle is much more rapid under anaerobic conditions. (2) That the onset of the characteristic contracture produced by IAA is accompanied always by an increase in the rate of oxygen consumption.


1996 ◽  
Vol 271 (3) ◽  
pp. F717-F722
Author(s):  
G. Bajaj ◽  
M. Baum

Intracellular cystine loading by use of cystine dimethyl ester (CDME) results in a generalized inhibition in proximal tubule transport due, in part, to a decrease in intracellular ATP. The present study examined the importance of phosphate and metabolic substrates in the proximal tubule dysfunction produced by cystine loading. Proximal tubule intracellular phosphorus was 1.8 +/- 0.1 in control tubules and 1.1 +/- 0.1 nmol/mg protein in proximal tubules incubated in vitro with CDME P < 0.001). Infusion of sodium phosphate in rabbits and subsequent incubation of proximal tubules with a high-phosphate medium attenuated the decrease in proximal tubule respiration and prevented the decrease in intracellular ATP with cystine loading. Tricarboxylic acid cycle intermediates have been shown to preserve oxidative metabolism in phosphate-depleted proximal tubules. In proximal tubules incubated with either 1 mM valerate or butyrate, there was a 42 and 34% reduction (both P < 0.05) in the rate of oxygen consumption with cystine loading. However, tubules incubated with 1 mM succinate or citrate had only a 13 and 14% P = NS) reduction in the rate of oxygen consumption, respectively. These data are consistent with a limitation of intracellular phosphate in the pathogenesis of the proximal tubule dysfunction with cystine loading.


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