Acetoacetate turnover and oxidation rates in ovine pregnancy ketosis

1964 ◽  
Vol 206 (2) ◽  
pp. 449-452 ◽  
Author(s):  
E. N. Bergman ◽  
K. Kon
Keyword(s):  
Turnover Rate ◽  
Ketone Bodies ◽  
Plasma Concentrations ◽  
Turnover Rates ◽  
Acetoacetic Acid ◽  
Oxidation Rates ◽  
Tracer Dose ◽  
Pregnant Sheep ◽  
The Mean ◽  
Normal Twin

Labeled acetoacetic acid (AcAc) was administered as a tracer dose and as a continuous infusion to 24 twin-pregnant ewes with varying degrees of spontaneous or fasting hypoglycemic ketosis. The mean AcAc turnover rate of five normal twin-pregnant sheep (plasma AcAc < 1 mg/100 ml) was only 0.04 g/hr kg3/4 or 1.0 g/sheep hr. During ketosis the turnover rate of AcAc was directly proportional to the plasma AcAc concentration until a maximal concentration of about 10 mg/100 ml was attained (total ketone bodies, expressed as acetone, would be about 20 mg/100 ml). At higher plasma concentrations, the AcAc turnover rates remained constant at nearly 0.4 g/hr kg3/4 (9 g/sheep hr). About one-half of this AcAc was oxidized to CO2 regardless of the actual amount utilized. The mean percentage of the total exhaled CO2 derived from AcAc metabolism increased from 2% in normal ewes to a maximum of about 20% during pregnancy ketosis. Comparisons of these data to values obtained in previous experiments on artificially ketotic nonpregnant sheep indicate that an overproduction of ketone bodies, rather than an underutilization, is the major cause of ruminant ketosis.

Quantitative measurements of acetoacetate metabolism and oxidation in sheep

1963 ◽  
Vol 205 (4) ◽  
pp. 658-662 ◽  
Author(s):  
E. N. Bergman ◽  
K. Kon ◽  
M. L. Katz
Keyword(s):  
Continuous Infusion ◽  
Ketone Bodies ◽  
Plasma Concentrations ◽  
Turnover Rates ◽  
Acetoacetic Acid ◽  
Quantitative Measurements ◽  
Intravenous Infusions ◽  
Specific Activities ◽  
Maximal Capacity

Ketosis was produced in sheep by intravenous infusions of large quantities of acetoacetic acid (AcAc). At the infusion rates employed less than 5% was excreted in the urine. Acetoacetic acid-3-C14 was administered also as a continuous infusion to both normal and ketotic sheep. Constant plasma concentrations and specific activities were obtained and with known C14 infusion rates, several parameters of AcAc metabolism were calculated. Mean endogenous AcAc turnover rates were about 0.04 g/hr kg3/4 (<1 g/sheep hr) but the maximal capacity of ketotic sheep to utilize AcAc was about 10-fold greater. In both normal and ketotic ewes, about one-half of the utilized AcAc was oxidized to CO2. The percentage of the total respired CO2 derived from AcAc metabolism increased from about 2% in normal ewes to over 30% during ketosis. The results indicate that the metabolism of ketone bodies by the normal ruminant is relatively insignificant but that, during ketosis, their contribution to the animal's total metabolism can be of major importance.

Quantitative aspects of glucose metabolism in pregnant and nonpregnant sheep

1963 ◽  
Vol 204 (1) ◽  
pp. 147-152 ◽  
Author(s):  
E. N. Bergman
Keyword(s):  
Glucose Oxidation ◽  
Glucose Utilization ◽  
The Body ◽  
Glucose Turnover ◽  
Turnover Rates ◽  
Pregnant Sheep ◽  
The Mean ◽  
Total Glucose ◽  
Mean Glucose ◽  
Pool Sizes

Labeled glucose was infused into four groups of ewes: nonpregnant fed; nonpregnant fasted; twin-pregnant fed; and twin-pregnant hypoglycemic and ketonemic. Mean glucose pool sizes were 157 and 127 mg/kg in nonpregnant and pregnant ewes, respectively, with decreased values in both fasting and hypoglycemia. Nonpregnant animals had glucose turnover rates averaging 4.0 g/hr (0.22 g/hr·kg3/4) when fed and only 2.7 g/hr (0.15 g/hr·kg3/4) after fasting. These values were only 60–80% of that of pregnant sheep, implying that glucose utilization due to twin-pregnancy was 20–40% of the total. The mean glucose space was about 27% of the body weight, indicating predominantly extracellular distribution of glucose even in hypoglycemia. In all animals about 8–10% of the exhaled CO2 was found to be derived from glucose oxidation and about one-third of the total glucose turnover was used for CO2 production. Comparisons of these data to values obtained from other mammals indicated further that there is a lower rate of glucose oxidation and metabolism in ruminants.

Water content and water turnover in beef cattle

1968 ◽  
Vol 19 (1) ◽  
pp. 129
Author(s):  
PH Springell
Keyword(s):  
Water Content ◽  
Half Life ◽  
Turnover Rate ◽  
Tritiated Water ◽  
Body Water ◽  
The Body ◽  
Turnover Rates ◽  
Water Turnover ◽  
Poor Diet ◽  
The Mean

Twenty-four steers, comprising British (Hereford and Hereford x Shorthorn), Zebu (Africander), and Zebu cross (British x Brahman or Africander) breeds, were either maintained on pasture, or yarded and fed on diets of a low and a high nutritional value. Tritiated water was injected into the animals on five occasions at intervals of 3 months. The body water content and the water turnover rate were calculated, and some of the sources of variation defined. Observed differences in the water content are attributable to nutritional factors rather than to breed differences. The mean body water content ranged from 615 to 809 ml/kg fasting body weight, where the higher values were associated with a poor diet. The mean half-life of tritiated water was lower in summer (as low as 58 hr) than in winter (up to 128 hr) in grazing and well-fed yarded steers. On a poor diet, however, the half-life in yarded cattle remained high and almost constant throughout the year, dropping to below 100 hr on only a single occasion. Occasionally the half-life was breed dependent, but generally no significant differences between breeds could be found. While mean turnover rates of up to 7.1 ml kg-1 hr-1 were found in better-fed cattle in summer, the value in poorly fed animals was almost constant throughout the year at about 3.3 ml kg-1 hr-1. There was, however, a winter minimum in the well-fed yarded and grazing groups. The turnover rate was also influenced by breed only to a limited extent. The results are interpreted in the light of their possible significance in the adaptation to a tropical environment, and in relation to their value in predicting the body composition.

scholarly journals THE KINETICS OF IRON METABOLISM IN NORMAL GROWING SWINE

1956 ◽  
Vol 103 (1) ◽  
pp. 145-159 ◽  
Author(s):  
W. N. Jensen ◽  
J. A. Bush ◽  
Helen Ashenbrucker ◽  
G. E. Cartwright ◽  
M. M. Wintrobe
Keyword(s):  
Life Span ◽  
Turnover Rate ◽  
Cell Mass ◽  
Red Cell ◽  
Turnover Rates ◽  
Plasma Iron ◽  
Cell Life ◽  
Average Maximum ◽  
The Mean ◽  
Exponential Rates

Plasma and red cell iron turnover rates were determined in 18 normal growing swine by the use of tracer doses of Fe59. Body surface counting was performed on a representative group of animals following the injection of the isotope. The mean half-time of plasma iron disappearance was 1.19 ± 0.26 hours. Two exponential rates of disappearance of Fe59 from the plasma were observed in 15 of the pigs and a single rate was observed in the other 3. The mean plasma iron turnover rate was 1.11 ± 0.34 mg./kg. day. The average maximum incorporation of Fe59 into the erythrocytes was 92 ± 9 per cent. The mean red cell iron incorporation rate was 1.10 mg./kg. day, but an average of 0.42 mg./kg. day of this was calculated as being due to increasing red cell mass incidental to body growth, so that the true mean red cell iron turnover rate was 0.59 ± 0.19 mg./kg. day. The average "apparent" red cell life span was 63 ± 16 days. This is in agreement with the red cell life span of 62 days determined previously with glycine-2-C14.

scholarly journals Turnover rates of ketone bodies in normal, starved and alloxan-diabetic rats

1968 ◽  
Vol 110 (4) ◽  
pp. 655-661 ◽  
Author(s):  
Margaret W. Bates ◽  
H. A. Krebs ◽  
D. H. Williamson
Keyword(s):  
Ketone Body ◽  
Alloxan Diabetes ◽  
Ketone Bodies ◽  
Diabetic Rats ◽  
Turnover Rates ◽  
Blood Concentrations ◽  
Order Of Magnitude ◽  
The Mean ◽  
Body Production ◽  
Body Concentration

1. Rates of appearance and disappearance of total ketone bodies were determined in normal, starved and alloxan-diabetic rats by measuring specific radioactivities and concentrations of blood acetoacetate and 3-hydroxybutyrate at different times after injection of 3-hydroxy[14C]butyrate. 2. The mean rates of appearance were 1·7, 4·2 and 10·9μmoles/min./100g. body wt. respectively for normal, starved and alloxan-diabetic rats. The rates of disappearance were of the same order of magnitude as the rates of appearance. 3. There was a direct correlation between the rates of appearance and disappearance and the blood concentrations of the ketone bodies. 4. The results indicate that in the rat increased ketone-body production is paralleled by increased ketone-body utilization and that the raised ketone-body concentration in the blood in starvation and alloxan-diabetes is due to a slight imbalance between the rates of production and utilization. 5. The findings are discussed in relation to the concept that ketone bodies can serve as fuels of respiration when the supply of carbohydrate is limited.

scholarly journals Patterns of Granulocyte Kinetics in Health, Infection and in Carcinoma

Blood ◽  
1965 ◽  
Vol 25 (5) ◽  
pp. 683-692 ◽  
Author(s):  
PETER R. GALBRAITH ◽  
LESLIE S. VALBERG ◽  
MALCOLM BROWN
Keyword(s):  
Steady State ◽  
Half Life ◽  
Turnover Rate ◽  
Turnover Rates ◽  
Normal Range ◽  
Control Value ◽  
Control Subjects ◽  
The Mean ◽  
Blood Granulocyte

Abstract Leukokinetic studies were performed using granulocytes labeled in vitro with radioactive diisopropylfluorophosphate (DFP32). The half-time of the granulocytes in the circulation, blood granulocyte mass and granulocyte turnover rates were determined. In control subjects the mean half-life was 6.44 hours with a range of 5.1 to 7.7 hours. The mean blood granulocyte mass was 38 x 109 cells with a range of 19.9 to 36.4 x 109 cells and the granulocyte turnover rate was 4.08 x 109 cells per hour with a range of 2.51 to 5.50 x 109 cells per hour. There was a direct relationship between the half-life and the blood granulocyte mass in the control subjects. In 6 subjects with infection the blood granulocyte mass was uniformly increased. The mean half-life and mean granulocyte turnover rate were both increased above the normal range. In 11 subjects with carcinoma several different leukokinetic patterns were found. The blood granulocyte mass was raised in 5 patients, but in only one of these was the granulocyte turnover rate increased above the normal range. In 6 subjects the blood granulocyte mass was within the normal range and deviations from the mean control value were accompanied by proportionate changes in the granulocyte turnover rate in all but 1 patient. No relation was found between the half-life and the blood granulocyte mass in subjects with infection and/or carcinoma. The possibility that this was due to the establishment of a new steady state of blood granulocyte mass at altered levels of granulocyte production, or that steady state conditions did not exist has been considered. However the data are interpreted no evidence for suppressed granulopoiesis was found in subjects with advanced malignant disease.

Differences in feed intake and the performance of Finn × Dorset ewes during late pregnancy

1975 ◽  
Vol 20 (3) ◽  
pp. 391-400 ◽  
Author(s):  
Y. Shevah ◽  
W. J. M. Black ◽  
R. B. Land
Keyword(s):  
Birth Weight ◽  
Ketone Bodies ◽  
Plasma Concentrations ◽  
Live Weight ◽  
Late Pregnancy ◽  
Experimental Period ◽  
Treatment Groups ◽  
Loss Of Weight ◽  
Plasma Ffa ◽  
The Mean

SUMMARYIn two experiments carried out in the autumn of 1971 and 1972 (treatment prefixes 1 and 2 respectively), 84 Finn x Dorset ewes found by X-ray to carry from 1 to 4 foetuses were individually fed during the last 6 weeks of gestation either: 1A, ad libitum; 1H and 2H, 33 kcal M/kg ewe live weight+365 kcal per ME/kg foetus (anticipated birth weight); 1M, 80%; and 2L, 50% of the total energy fed to treatments 1H and 2H. The amounts given remained constant during the experimental period. The method of feeding according to foetal number within treatments, attempted to standardize the nutritional state within treatments.All ewes (except those on 2L which remained constant) gained 6 to 8 kg live weight during the last 6 weeks of gestation and lost 8 to 10 kg at parturition. The birth weight of lambs was not affected by the range of energy (2·3 to 4·4 Meal ME/ewe per day) consumed during the last 6 weeks of gestation.Plasma concentrations of free fatty acids (FFA), glucose and ketone bodies were determined weekly. The mean FFA levels were significantly higher in the low energy treatment groups than the high ones.The present data indicated that if there is little change in body weight i n the early stages of pregnancy a 65 kg ewe bearing twin lambs, will require about 4 Meal ME/day during the last 50 days of gestation t o prevent a rise in plasma FFA concentration or loss of weight over the gestation period.

Diurnal variation in the chemical composition of plasma from lactating beef cows on three dietary energy intakes

1976 ◽  
Vol 86 (3) ◽  
pp. 595-602 ◽  
Author(s):  
C. R. E. Coggins ◽  
A. C. Field
Keyword(s):  
Diurnal Variation ◽  
Ketone Bodies ◽  
Plasma Concentrations ◽  
Beef Cows ◽  
Group Differences ◽  
Dietary Energy ◽  
Energy Status ◽  
Urea Nitrogen ◽  
The Mean ◽  
Calcium And Magnesium

SummaryTwenty-two beef cows, producing on average 5·5 kg 4% fat corrected milk per day, were offered diets of rolled barley and silage such that eight animals were consuming 70%, seven 95% and seven 120% of their estimated energy requirements. Blood samples were taken at intervals during the day and the plasma concentrations of glucose, free fatty acids (FFA), ketone bodies, total protein, albumin, globulin, urea nitrogen, calcium, inorganic phosphate, magnesium and copper determined.Diurnal variation was found in the plasma concentration of glucose, FFA, ketone bodies, urea nitrogen, albumin, calcium and magnesium; it was particularly marked for the first four constituents and appeared to be related to feeding.There were no overall significant differences between groups in the mean daily concentrations of the measures of energy status (glucose, FFA, ketone bodies), but significant (P < 0·001) prefeeding group differences were found in glucose and ketone body concentrations. No significant differences between groups were found for the remaining constituents.There was a postprandial depression in plasma glucose concentration, which was positively correlated with FFA concentration.

scholarly journals Lipid metabolism in shorn and unshorn pregnant sheep

1989 ◽  
Vol 62 (1) ◽  
pp. 35-49 ◽  
Author(s):  
M. E. Symonds ◽  
M. J. Bryant ◽  
M. A. Lomax
Keyword(s):  
Lipid Metabolism ◽  
Palmitic Acid ◽  
Plasma Concentrations ◽  
Metabolizable Energy ◽  
Whole Body ◽  
Entry Rate ◽  
Fat Depots ◽  
Oxidation Rates ◽  
Pregnant Sheep ◽  
Pregnant Ewe

The aim of the present study was to determine how the long-term metabolic adaptations to winter shearing of the pregnant ewe result in significant changes in the rates of lipid mobilization and utilization of non-esterified fatty acids (NEFA) in comparison with unshorn controls. Continuous infusions of [1-14C]palmitic acid, [2-3H]glycerol and NaH14CO3 were used to measure whole-body lipid metabolism in fed (estimated metabolizable energy (ME) intake 9.54 MJ/d) and under-fed (estimated ME intake of 3 MJ/d), shorn and unshorn sheep over the final 4 weeks of pregnancy. Whole-body carbon dioxide, estimated heat production, total NEFA entry and oxidation rates were all significantly higher in fed shorn ewes compared with unshorn controls, even though there was no difference in the arterial plasma NEFA concentration. These differences may be mediated via an increase in the plasma concentrations of thyroid hormones in shorn animals. As a result of under-feeding any significant differences in lipid metabolism between shorn and unshorn groups were removed. In all sheep the mean total NEFA entry rate as measured using [1-14C]palmitic acid was 3.4 times the value obtained using [2-3H]glycerol. It is concluded that when sheep are fed on a diet from which no more than half the required ME for late pregnancy is obtained, then lipolysis of body fat depots occurs via the incomplete breakdown of adipose tissue triglycerides. This effect is significantly greater in the fed shorn pregnant ewe which exhibits higher entry and oxidation rates of NEFA.

Corrigendum - Water content and water turnover in beef cattle

1968 ◽  
Vol 19 (1) ◽  
pp. 129
Author(s):  
PH Springell
Keyword(s):  
Water Content ◽  
Half Life ◽  
Turnover Rate ◽  
Tritiated Water ◽  
Body Water ◽  
The Body ◽  
Turnover Rates ◽  
Water Turnover ◽  
Poor Diet ◽  
The Mean

Twenty-four steers, comprising British (Hereford and Hereford x Shorthorn), Zebu (Africander), and Zebu cross (British x Brahman or Africander) breeds, were either maintained on pasture, or yarded and fed on diets of a low and a high nutritional value. Tritiated water was injected into the animals on five occasions at intervals of 3 months. The body water content and the water turnover rate were calculated, and some of the sources of variation defined. Observed differences in the water content are attributable to nutritional factors rather than to breed differences. The mean body water content ranged from 615 to 809 ml/kg fasting body weight, where the higher values were associated with a poor diet. The mean half-life of tritiated water was lower in summer (as low as 58 hr) than in winter (up to 128 hr) in grazing and well-fed yarded steers. On a poor diet, however, the half-life in yarded cattle remained high and almost constant throughout the year, dropping to below 100 hr on only a single occasion. Occasionally the half-life was breed dependent, but generally no significant differences between breeds could be found. While mean turnover rates of up to 7.1 ml kg-1 hr-1 were found in better-fed cattle in summer, the value in poorly fed animals was almost constant throughout the year at about 3.3 ml kg-1 hr-1. There was, however, a winter minimum in the well-fed yarded and grazing groups. The turnover rate was also influenced by breed only to a limited extent. The results are interpreted in the light of their possible significance in the adaptation to a tropical environment, and in relation to their value in predicting the body composition.

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