Seasonal changes in total body water, extracellular fluid, and blood volume in grazing reindeer

1972 ◽  
Vol 50 (1) ◽  
pp. 107-116 ◽  
Author(s):  
R. D. Cameron ◽  
J. R. Luick

The effects of climatic and nutritional changes on body fluid compartmentalization and turnover were investigated in grazing female reindeer. Total body water volume and turnover, extracellular fluid volume, and blood volume were estimated using tritiated water, sodium sulfate-35S, and sodium chromate-51Cr, respectively. During winter and spring, body weights were either maintained or reduced while total body water (percentage of body weight) increased, resulting in appreciable losses of total body solids. In summer, large gains in body weight were accompanied by reduced total body water volumes resulting in substantial increases in body solids. An apparent fluid shift from the intravascular to the extracellular compartment during late spring suggested the occurrence of a starvation edema. Mean water flux rates (ml/day per kilogram body weight) were higher in late spring than during other seasons; lowest values were recorded in early winter. Seasonal variations in nutritional status as reflected by body composition and fluid compartmentalization, and changes in water turnover are discussed in relation to climate and the quality and availability of forage. The complicating influences of pregnancy and lactation are also considered.

1969 ◽  
Vol 72 (1) ◽  
pp. 31-40 ◽  
Author(s):  
W. R. McManus ◽  
R. K. Prichard ◽  
Carolyn Baker ◽  
M. V. Petruchenia

SUMMARYThe use of tritiated water to estimate total body-water content of animals experiencing recovery from under-nutrition was studied.The time for equilibration of tritiated water (TOH), given intraperitoneally, with total body water (TBW) was determined in rabbits and in rats. As judged by the specific activity of blood water, equilibration had occurred by 76–125 min in the rabbit and did not appear to be affected by the plane of nutrition. However, between slaughter groups the specific activity of water obtained from the liver 180 min after injection of TOH was significantly different from the specific activity of water simultaneously obtained from the blood plasma. It is concluded that the liver is not a suitable tissue to use for testing achievement of equilibration.As judged by the specific activity of blood water compared to that of water from the whole body macerate, equilibration in mature rats either in stable body condition or undergoing rapid compensatory growth occurred in less than 60 min.A trial comparing TOH-space (corrected by 3% body weight) and actual TBW (by desiccation) was conducted on thirty rabbits which experienced under-nutrition followed by compensatory growth.Prior to under-nutrition the agreement between actual and estimated TBW was satisfactory and within 2·3%. During compensatory growth the agreement was poor— the TOH values over-estimating actual TBW by about 12%.A trial with mature rats confirmed the findings with rabbits. For rats in stable body weight the mean estimated TOH-space for fourteen animals was within 1·2% of the actual TBW. For fourteen rats undergoing compensatory growth the mean estimated TOH-space (corrected by 3% body weight) overestimated actual TBW by 6·2%.


1976 ◽  
Vol 54 (6) ◽  
pp. 857-862 ◽  
Author(s):  
R. D. Cameron ◽  
R. G. White ◽  
J. R. Luick

The accuracy of the tritium water dilution method in estimating water flux was evaluated in reindeer under various conditions of temperature and diet. Two non-pregnant female reindeer were restrained in metabolism stalls, within controlled-environment chambers, at temperatures of + 10, −5, and −20 °C; varying amounts of a commercial pelleted ration (crude protein, 13%) or mixed lichens (crude protein, 3%) were offered, and water was provided ad libitum either as snow or in liquid form. Total body water volume and water turnover were estimated using tritiated water, and the daily outputs of feces and urine were measured for each of 12 different combinations of diet and temperature. Statistical analysis of the data showed that the tritium water dilution technique gives accurate determinations of total body water flux over a wide range of environmental and nutritional conditions.


1988 ◽  
Vol 47 (3) ◽  
pp. 435-445 ◽  
Author(s):  
F. R. Dunshea ◽  
A. W. Bell ◽  
K. D. Chandler ◽  
T. E. Trigg

ABSTRACTA two-pool model of tritiated water kinetics was investigated as a means of partitioning total body water into empty body water and gut water in 17 lactating goats. Empty body water, gut water and total body water were of a similar magnitude to, and highly correlated with, a rapidly equilibrating tritiated water pool, a more slowly equilibrating pool and the sum of these two pools, respectively.Empty body fat was poorly correlated with both live weight and empty body weight (R2 = 0·42 and 0·51, respectively). However, there was a strong inverse relationship between the water and fat contents of the empty body. Consequently, empty body fat was accurately predicted by a multiple regression equation which included both empty body weight and empty body water as independent variables (R2 = 0·97). Substitution of these variables with estimates derived from tritiated water kinetics still resulted in a high correlation (R2 = 0·88). Tritiated water kinetics offered little improvement over live weight alone in the prediction of empty body protein, empty body ash or fat-free empty body.


1974 ◽  
Vol 82 (1) ◽  
pp. 105-112 ◽  
Author(s):  
B. S. W. Smith ◽  
A. R. Sykes

SUMMARYEight mature female sheep were offered a ration which maintained body weight constant during a 20-week period. During the final 10 weeks a comparison was made in each animal of the pattern of equilibration and urinary losses of tritiated water during 8 h after dosing by four different routes. These were intravenous, intraperitoneal, intraruminal and a combination of the intraperitoneal and intraruminal routes. Tritiated water spaces were calculated from (a) the 8-h plasma specific activity and (b) by extrapolation to zero time of the plasma specific activities during the 7 days after injection. At the end of the experiment the fat and water contents of the bodies of the sheep were determined directly.Complete equilibration of tritiated water between plasma and rumen water was not achieved in all animals 8 h after intravenous or intraperitoneal injection but was when the rumen was primed by the combination of intraperitoneal and intraruminal dosing. After intraruminal dosing equilibration was not achieved in any animal within 8 h of dosing.Urinary losses of marker were lower after intraruminal dosing but otherwise averaged 4–5 % of the dose/1 urine. This was equivalent to 0·3–6·7% of the dose for individual sheep.Errors resulting from incomplete equilibration and urinary loss of marker did not influence the efficiency of prediction of total body water from tritiated water space. The multiple correlation coefficient relating body fat with empty body weight and its water content was very high (r = 0·99). Errors introduced into this relationship by the inclusion of gut water in the prediction equations were apparently of a similar magnitude to those resulting from the errors in the estimation of tritiated water space.The extrapolation method for the determination of tritiated water space was shown to have the same accuracy as equilibration techniques under these controlled dietary conditions.


1977 ◽  
Vol 232 (1) ◽  
pp. R60-R65 ◽  
Author(s):  
J. M. Culebras ◽  
G. F. Fitzpatrick ◽  
M. F. Brennan ◽  
C. M. Boyden ◽  
F. D. Moore

Total body water (TBW) determination by tritium space could be factitiously elevated by exchangeable H+ contained within water-soluble chemical configurations. Should this nonaqueous (molecular) exchangeable H+ turn out to be a large fraction of total exchangeable H+, TBW measurement by tritiated water (THO) dilution would display a systematic upward and non-random error. TBW was measured by THO dilution and subsequently by total body desiccation in 21 rats (weight 227+/-83 g, mean+/-SD). TBW was 71.38+/-2.4% by THO dilution and 70.20+/-1.5% by body desiccation. Analysis of variance of TBW vs. body weight showed a highly significant correlation both with desiccation (P less than 0.0005, r=-0.78) and dilution (P less than 0.03, r= -0.50). Convariance analysis of both methods showed no difference in slope (P greater than 0.9). There was a difference in variance (P less than 0.001) and means (P less than 0.03). Tritium space is 1.2% of body weight larger than TBW measured by desiccation. TBW measured by THO dilution gives a 1.71% overestimation of TBW as measured by desiccation. TBW measurement by THO dilution is accurate within less than 2% error. These findings have particular significance in the light of our theoretical model of the total nonaqueous exchangeable H+ in fat, protein, and carbodhydrate in the living vertebrate.


1956 ◽  
Vol 34 (5) ◽  
pp. 959-966 ◽  
Author(s):  
C. Deb ◽  
J. S. Hart

Body fluid volumes and hematological values have been compared in rats exposed to 6 °C. for various periods of time and in rats at 30 °C. for comparable periods. Absolute blood and plasma volumes (T1824 space) decreased with time of exposure to 30 °C, while extracellular fluid volume (sodium space), total body water, and body weight increased. Rats transferred from the warm to the cold environment had larger plasma and blood volumes than those of rats at 30 °C. after the first week of exposure. After five weeks, blood volume was 22% greater on an absolute basis and 30% greater relative to total body water than that of the larger rats at 30 °C. There were no differences in extracellular fluid volumes between warm and cold exposed rats at comparable intervals. Total water and intracellular water tended to be greater in rats at 30 °C. on an absolute basis but they were much greater per unit body weight in rats at 6 °C. No differences were observed in red blood cell counts, in hemoglobin concentration, or in plasma specific gravity between warm and cold exposed rats, but there was an increased hematocrit, increased corpuscular volume, and decreased corpuscular hemoglobin content in rats kept at 6 °C. Hemoglobin, red cells, and plasma specific gravity increased with time in both groups.


Rangifer ◽  
1985 ◽  
Vol 5 (1) ◽  
pp. 2 ◽  
Author(s):  
Terje S. Larsen ◽  
Arnoldus Schytte Blix

<p>Total body water and water turnover were measured at different times throughout the year in 3 captive Norwegian reindeer, using a tritiated water dilution method (Holleman et al. 1982). Total body water (percent of body weight) increased during late autumn and winter, from 59.1 &plusmn; 1.5 % in October to 72.5 &plusmn; 2.0 % in April. Using the equatation by Pace and Rathbun (1945) for predicting total body fat (% fat = 100 - % water/0.732), this increase in total body water indicates a concomitant reduction in body fat, from a maximum value of 18.9 &plusmn; 2.6 % (of body weight) in October to a minimum of 0.9 &plusmn; 2.7 % in April. During summer, on the other hand, fat content increased at the expense of a reduced percentage of body water. Water turnover was low in winter (December - April), ranging between 30.8 &plusmn; 5.2and43.6 &plusmn; 13.5ml.d-'. kg-1, but increased nearly fourfold during summer (June-August) with a maximum of 117.7 &plusmn; 5.9 ml.d-1. kg-1 in August. Positive correlations between water turnover and food intake and between water turnover and ambient temperature were found, the latter probably resulting from an incidental correlation between food intake and ambient temperature.</p><p>Sesongmessige forandringer i totalt kroppsvann, kropps-sammensetning og vannomsetning hos reinsdyr.</p><p>Abstract in Norwegian / Sammendrag: Totalt kroppsvann og vannomsetning av vann ble m&aring;lt til forskjellige &aring;rstider i 3 norske reinsdyr ved hjelp av utvasking av tritiert vann (Holleman et al. 1982). Totalt kroppsvann (prosent av kroppsvekt) &oslash;kte utover h&oslash;sten og vinteren, fra 59.1 &plusmn; 1.5 % i oktober til 72.5 &plusmn; 2.0 % i april. Ved hjelp av en ligning som er gitt av Pace og Rathbun (1945) for beregning av totalt kroppsfett (% fett = 100 - % vann/0.732), fant en at denne &oslash;kningen i vanninnhold tilsvarte en samtidig reduksjon i fettinnhold, fra en maksimums-verdi p&aring; 18.9 &plusmn; 2.6 % av kroppsvekt i oktober til et minimum p&aring; 0.9 &plusmn; 2.7 % i april. Utover sommeren &oslash;kte derimot innholdet av fett p&aring; bekostning av vanninnholdet. Omsetningen av vann var lav vinterstid (desember - april), varierende mellom 30.8 &plusmn; 5.2 og 43.6 &plusmn; 13.5 ml.d-1.kg-1, men &oslash;kte nesten fire ganger i l&oslash;pet av sommeren (juni - august) til et maksimum p&aring; 117.7 &plusmn; 5.9 ml.d-1.kg-1 i august. Det ble funnet positive korrelasjoner mellom vannomsetning og forinntak og mellom vannomsetning og omgivelsestemperatur. Sistnevnte korrelasjon kan muligens skyldes en tilfeldig sammenheng mellom forinntak og omgivelsestemperatur.</p><p>Vuodenaikaiset muutokset poron ruumiin kokonaisvesim&aring;&aring;r&aring;ss&aring;, ruumiin koostumuksessa ja vesiaineenvaihdunnassa.</p><p>Abstract in Finnish / Yhteenveto: Ruumiin kokonaisvesima&aring;r&aring;&aring; ja vesiaineenvaihduntaa mitattiin eri vuodenaikoina 3 norjalaisella porolla k&aring;ytt&aring;m&aring;ll&aring; apuna tritioitua vetta (Holleman et al. 1982). Ruumiin kokonaisvesim&aring;ar&aring; (prosenttia ruumiinpainosta) lis&aring;antyi syksyll&aring; ja talvella lokakuun 59.1&plusmn;1.5%:sta 72.5&plusmn;2.0%:i huhtikuussa. K&aring;ytt&aring;m&aring;ll&aring; Pacen ja Rathbunin (1945) ruumiin kokonaisrasvapitoisuude laskukaavaa (rasva % = 100 - vesi %/0.732) huomattiin tam&aring;n vesim&aring;&aring;r&aring;n lisa&aring;ntymis johtuvan samanaikaisesta rasvapitoisuuden v&aring;henemisesta. Rasvapitoisuus laski lokakuun maksimiarvosta 18.9&plusmn;2.6% ruumiinpainosta huhtikuun minimiarvoon, joka oli 0.9&plusmn;2.7% ruumiinpainosta. Kes&aring;ll&aring; rasvapitoisuus lis&aring;antyi puolestaan vesipitoisuuden kustannuksella. Talvella j&aring;k&aring;l&aring;ravinnolla (joulu-huhtikuussa) veden kaytto vaihteli v&aring;lilla 30.8&plusmn;5.2 ja 43.6&plusmn;13.5 ml vrk-1kg-1 mutta se kohosi melkein nelinkertaisesti kesalla (kes&aring;-elokuussa) maksimiarvoonsa 117.7+5.9 ml vrk-1 kg-1 elokuussa. Veden k&aring;yton ja ravinnon oton seka veden k&aring;yton jaymp&aring;riston lampotilan v&aring;lilla oli positiivinen korrelaatio. Viimeksi mainittu korrelaatio voi johtua v&aring;liaikaisesta riippuvuudesta ravinnonoton ja ymp&aring;riston l&aring;mpotilan v&aring;lill&aring;.</p>


1977 ◽  
Vol 88 (3) ◽  
pp. 693-698 ◽  
Author(s):  
A. A. Degen

SUMMARYThe total body water (TBW), its distribution and water turnover were measured in native fat-tailed Awassi sheep, a breed well adapted to desert conditions, and in imported German Mutton Merino (GMM) sheep, a breed that evolved in a temperate climate, under semi-arid conditions.TBW (tritiated water space;TOH space), extracellular fluid volume (SCN-space) and plasma volume (T·1824 space) were measured during the summer while these sheep grazed natural pasture that remained as dried stem-cured hay and in the winter while they grazed lush natural pasture. No differences were found between the breeds in any of the measurements in both seasons. Within both breeds, the percentage TOH and SCN-spaces were larger in the summer whereas the percentage T·1824 space remained the same.TBW and water turnover were measured in these breeds in eight trials while the sheep grazed native pasture in the autumn, winter and spring, shrubs in the winter and legumes in the summer. Water and shade were freely and easily accessible throughout the grazing period. The TBW was found to be consistently lower in the Awassi, indicating a higher energy reserve. The water turnover in 1/24 h/kg wt.0·82 was found to be higher in the GMM in all trials; the differences ranged between 3 and 28%. However, in only two out of the eight trials were the differences significant. Thus, the water turnoverwas only slightly lower in the Awassi although this breed evolved under Middle Eastern arid and semi-arid regions.


1960 ◽  
Vol 199 (4) ◽  
pp. 661-665 ◽  
Author(s):  
Paul R. Schloerb

It was the purpose of this study to measure and to compare the volumes of distribution of creatinine, urea and tritiated water in nephrectomized dogs. After bilateral nephrectomy a solution containing known amounts of these was infused intravenously and at a constant rate in some studies. Frequent arterial blood samples were taken during and following infusion for periods up to 20 hours and were analyzed for water and the infused substances. The respective volumes of distribution and rates of dilution were calculated. Isotopic water and urea were distributed in 95% and creatinine in 61% of their final volumes of distribution at the end of a 30-minute infusion. Final equilibrium occurred in about 90 minutes with water and urea and in about 4 hours with creatinine. Creatinine became distributed in 99 ± 3% of the tritiated water volume and in 101 ± 5% of the urea volume. Urea distributed in 98 ± 4% of the tritiated water volume. It is concluded that administered creatinine is distributed in total body water of nephrectomized dogs with an equilibrium time of about 4 hours and that urea is similarly distributed within 1 1/2 hours.


1956 ◽  
Vol 34 (1) ◽  
pp. 959-966 ◽  
Author(s):  
C. Deb ◽  
J. S. Hart

Body fluid volumes and hematological values have been compared in rats exposed to 6 °C. for various periods of time and in rats at 30 °C. for comparable periods. Absolute blood and plasma volumes (T1824 space) decreased with time of exposure to 30 °C, while extracellular fluid volume (sodium space), total body water, and body weight increased. Rats transferred from the warm to the cold environment had larger plasma and blood volumes than those of rats at 30 °C. after the first week of exposure. After five weeks, blood volume was 22% greater on an absolute basis and 30% greater relative to total body water than that of the larger rats at 30 °C. There were no differences in extracellular fluid volumes between warm and cold exposed rats at comparable intervals. Total water and intracellular water tended to be greater in rats at 30 °C. on an absolute basis but they were much greater per unit body weight in rats at 6 °C. No differences were observed in red blood cell counts, in hemoglobin concentration, or in plasma specific gravity between warm and cold exposed rats, but there was an increased hematocrit, increased corpuscular volume, and decreased corpuscular hemoglobin content in rats kept at 6 °C. Hemoglobin, red cells, and plasma specific gravity increased with time in both groups.


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