Feed intake and production in sheep fed diets high in sodium and potassium

2005 ◽  
Vol 56 (5) ◽  
pp. 427 ◽  
Author(s):  
David G. Masters ◽  
Allan J. Rintoul ◽  
Robyn A. Dynes ◽  
Kelly L. Pearce ◽  
Hayley C. Norman
Keyword(s):  
Organic Matter ◽  
Feed Intake ◽  
Response Surfaces ◽  
Animal Production ◽  
High Potassium ◽  
Sodium Potassium ◽  
High Sodium ◽  
Wool Growth ◽  
Chloride Salts ◽  
Sodium And Potassium

Salinity is a problem facing many crop and livestock producers in southern Australia. One management option is to revegetate with salt-tolerant plants suitable for animal production. These plants are often halophytic shrubs containing up to 30% ash, predominantly as sodium, potassium, or chloride. This experiment examines the consequences of a high intake of sodium and potassium separately or together on feed intake, digestibility, liveweight change, and wool growth. Twelve groups of 6 weaner wethers were allocated to treatments according to a balanced 3 × 4 factorial design with 3 levels of added potassium (0, 0.38, and 0.77 mol/kg DM equivalent to 0, 15, and 30 g/kg DM) and 4 levels of added sodium (0, 0.87, 2.18, and 3.48 mol/kg DM, equivalent to 0, 20, 50, and 80 g/kg DM) as the chloride salts. The treatment diets were fed to sheep for 6 weeks. Increasing sodium in the diet significantly decreased feed intake, digestibility, liveweight gain, and wool growth either as a main effect or through an interaction with potassium. Organic matter intake was reduced from 1.35 kg at the lowest levels of sodium and potassium to 0.67 kg at the highest levels. Comparing the same 2 groups, liveweight gain was reduced from 144 to 0 g/day, organic matter digestibility from 59.1% to 57.3%, and wool growth from 1.21 to 1.04 mg/cm2.day. The response surfaces indicate that production was depressed even at the lower levels of sodium, whereas high potassium depressed intake, digestibility, and liveweight gain at high levels of sodium only. The interaction between sodium and potassium was always negative at high levels of sodium, indicating that manipulation of the proportions of the 2 elements is unlikely to provide benefits for animal production when total salt levels are high. Although wool growth was depressed at high sodium and potassium, the efficiency of wool growth increased from 10.0 to 15.4 g/kg organic matter intake when the lowest and highest levels of the sodium and potassium were compared. This result may present significant opportunities for the use of saline land to grow fine wool.

scholarly journals Joint association of urinary sodium and potassium excretion with cardiovascular events and mortality: prospective cohort study

BMJ ◽  
2019 ◽  
pp. l772 ◽  
Author(s):  
Martin O’Donnell ◽  
Andrew Mente ◽  
Sumathy Rangarajan ◽  
Matthew J McQueen ◽  
Neil O’Leary ◽  
...  
Keyword(s):  
Urinary Excretion ◽  
Sodium Excretion ◽  
Cardiovascular Events ◽  
Sodium Intake ◽  
Urinary Sodium ◽  
Potassium Excretion ◽  
High Potassium ◽  
High Sodium ◽  
Low Sodium ◽  
Sodium And Potassium

AbstractObjectiveTo evaluate the joint association of sodium and potassium urinary excretion (as surrogate measures of intake) with cardiovascular events and mortality, in the context of current World Health Organization recommendations for daily intake (<2.0 g sodium, >3.5 g potassium) in adults.DesignInternational prospective cohort study.Setting18 high, middle, and low income countries, sampled from urban and rural communities.Participants103 570 people who provided morning fasting urine samples.Main outcome measuresAssociation of estimated 24 hour urinary sodium and potassium excretion (surrogates for intake) with all cause mortality and major cardiovascular events, using multivariable Cox regression. A six category variable for joint sodium and potassium was generated: sodium excretion (low (<3 g/day), moderate (3-5 g/day), and high (>5 g/day) sodium intakes) by potassium excretion (greater/equal or less than median 2.1 g/day).ResultsMean estimated sodium and potassium urinary excretion were 4.93 g/day and 2.12 g/day, respectively. After a median follow-up of 8.2 years, 7884 (6.1%) participants had died or experienced a major cardiovascular event. Increasing urinary sodium excretion was positively associated with increasing potassium excretion (unadjusted r=0.34), and only 0.002% had a concomitant urinary excretion of <2.0 g/day of sodium and >3.5 g/day of potassium. A J-shaped association was observed of sodium excretion and inverse association of potassium excretion with death and cardiovascular events. For joint sodium and potassium excretion categories, the lowest risk of death and cardiovascular events occurred in the group with moderate sodium excretion (3-5 g/day) and higher potassium excretion (21.9% of cohort). Compared with this reference group, the combinations of low potassium with low sodium excretion (hazard ratio 1.23, 1.11 to 1.37; 7.4% of cohort) and low potassium with high sodium excretion (1.21, 1.11 to 1.32; 13.8% of cohort) were associated with the highest risk, followed by low sodium excretion (1.19, 1.02 to 1.38; 3.3% of cohort) and high sodium excretion (1.10, 1.02 to 1.18; 29.6% of cohort) among those with potassium excretion greater than the median. Higher potassium excretion attenuated the increased cardiovascular risk associated with high sodium excretion (P for interaction=0.007).ConclusionsThese findings suggest that the simultaneous target of low sodium intake (<2 g/day) with high potassium intake (>3.5 g/day) is extremely uncommon. Combined moderate sodium intake (3-5 g/day) with high potassium intake is associated with the lowest risk of mortality and cardiovascular events.

CHEMICAL METHOD FOR THE DETERMINATION OF URINARY ALDOSTERONE

1957 ◽  
Vol 35 (1) ◽  
pp. 425-443 ◽  
Author(s):  
Wojciech Nowaczynski ◽  
Erich Koiw ◽  
Jacques Genest
Keyword(s):  
Normal Subjects ◽  
Ultraviolet Absorption ◽  
Anxiety State ◽  
High Potassium ◽  
High Sodium ◽  
Pregnancy Anxiety ◽  
Potassium Intake ◽  
High Degree ◽  
Sodium And Potassium

A new method of purification of crude neutral extracts of urine for the isolation and determination of aldosterone is presented. The specificity and accuracy of the method depend upon the high degree of purity of the aldosterone isolated. The assertion that the substance isolated is aldosterone is based on the mobilities in the three chromatographic systems used, on the typical ultraviolet absorption curve, on the satisfactory agreement between the values obtained by ultraviolet absorption and by blue tetrazolium reaction, and by the typical chromogen spectra in concentrated sulphuric acid and in 100% phosphoric acid. Values obtained in nine normal subjects on ordinary diets vary from 2.2 to 10 μg. per day with a mean of 5.1. Illustrations of results obtained during pregnancy, anxiety state, and periods of high potassium and combined high sodium and potassium intake are presented.

Stimulation of wool growth by thyroxine implantation. II. Feed intake of grazing Merino wethers treated repeatedly with thyroxine.

1964 ◽  
Vol 15 (4) ◽  
pp. 676 ◽  
Author(s):  
LJ Lambourne
Keyword(s):  
Organic Matter ◽  
Feed Intake ◽  
Sheep Grazing ◽  
Wool Production ◽  
Wool Growth ◽  
Digestible Organic Matter ◽  
The Difference ◽  
Maintenance Requirements ◽  
Substantial Rise ◽  
Stimulation Of

Estimates have been made of the feed intake of wethers that received implantations of 60 mg thyroxine every 3 months, and of untreated sheep, grazing together. The estimated intake of digestible organic matter (D.O.M.) by treated wethers was higher than that of controls in 24 out of 27 measurement periods. The difference in feed intake was least in the iirst month after implantation, when the treated sheep lost weight, and greatest in the second and third months when the treated sheep were regaining weight. The overall increase in intake resulting from thyroxine treatment (20–25%) was greater than the increase in wool production (7% greasy weight, 3-7 % clean weight), and the efficiency of wool production was therefore lower in thyroxinetreated wethers. From the relationships between feed intake and rate of weight change it was concluded that in the month after implantation, when pulse rates indicated a substantial rise in metabolic rate, the maintenance feed requirement was raised from about 560 g to about 780 g D.O.M. per day. Observations in two winters with recently shorn sheep gave estimates of maintenance requirements for untreated wethers ranging from 850 to 1300 g D.O.M. per day. During recovery from repeated thyroxine implantation the wethers gained in weight no more efficiently than the controls. The mechanism of action of exogenous thyroxine is discussed in the light of these and other data.

CHEMICAL METHOD FOR THE DETERMINATION OF URINARY ALDOSTERONE

1957 ◽  
Vol 35 (6) ◽  
pp. 425-443 ◽  
Author(s):  
Wojciech Nowaczynski ◽  
Erich Koiw ◽  
Jacques Genest
Keyword(s):  
Normal Subjects ◽  
Ultraviolet Absorption ◽  
Anxiety State ◽  
High Potassium ◽  
High Sodium ◽  
Pregnancy Anxiety ◽  
Potassium Intake ◽  
High Degree ◽  
Sodium And Potassium

A new method of purification of crude neutral extracts of urine for the isolation and determination of aldosterone is presented. The specificity and accuracy of the method depend upon the high degree of purity of the aldosterone isolated. The assertion that the substance isolated is aldosterone is based on the mobilities in the three chromatographic systems used, on the typical ultraviolet absorption curve, on the satisfactory agreement between the values obtained by ultraviolet absorption and by blue tetrazolium reaction, and by the typical chromogen spectra in concentrated sulphuric acid and in 100% phosphoric acid. Values obtained in nine normal subjects on ordinary diets vary from 2.2 to 10 μg. per day with a mean of 5.1. Illustrations of results obtained during pregnancy, anxiety state, and periods of high potassium and combined high sodium and potassium intake are presented.

Characteristics of potassium conservation by the dog kidney

1964 ◽  
Vol 206 (4) ◽  
pp. 743-749 ◽  
Author(s):  
Guy Lemieux ◽  
Yves Warren ◽  
Marc Gervais
Keyword(s):  
Urinary Excretion ◽  
Sodium Intake ◽  
Renal Tubules ◽  
Sodium Potassium ◽  
High Sodium ◽  
High Sodium Intake ◽  
Dog Kidney ◽  
Potassium Restriction ◽  
Potassium Exchange ◽  
Sodium And Potassium

During simultaneous restriction of sodium and potassium to 1 and 2 mEq/day, respectively, it has been demonstrated that the dog kidney has a remarkable capacity to conserve potassium, the urinary excretion of this ion decreasing rapidly to equal the intake within 4–5 days. Subsequent administration of sodium 100 mEq/day in the form of chloride failed to influence renal conservation of potassium. Equivalent administration of sodium in the form of sulfate or neutral phosphate resulted in a transient but unequivocal increase in urinary excretion of potassium. When desoxycorticosterone 1 mg/kg day was given while high sodium intake and potassium restriction was continued, significant increase in urinary excretion of potassium was observed regardless of the anionic form in which sodium was given. It is suggested that chloride, a readily permeant anion, may prevent significant tubular sodium-potassium exchange. This effect would appear to be overcome when large amount of mineralocorticoid is acting on the renal tubules.

ALTERATIONS OF ALDOSTERONE BIOSYNTHESIS BY RAT ADRENAL TISSUE DUE TO INCREASED INTAKE OF SODIUM AND POTASSIUM

1968 ◽  
Vol 58 (1) ◽  
pp. 27-37 ◽  
Author(s):  
Jürg Müller
Keyword(s):  
Adrenal Glands ◽  
Sodium Intake ◽  
Potassium Ions ◽  
High Potassium ◽  
High Sodium ◽  
Potassium Intake ◽  
High Sodium Intake ◽  
Test Conditions ◽  
Sodium And Potassium

ABSTRACT Three groups of rats received respectively the following drinking fluids for two weeks: sucrose 5%; NaCl 0.154 m + sucrose; KCl 0.154 m+ sucrose. Aldosterone biosynthesis by quartered adrenal glands of these animals was studied under various in vitro conditions. Adrenals from rats drinking sucrose alone produced significantly more aldosterone under all conditions of incubation than adrenals from rats drinking NaCl, which produced more corticosterone and deoxycorticosterone. Tissue from animals drinking NaCl converted less unlabelled progesterone, 11β-hydroxyprogesterone, deoxycorticosterone and corticosterone to aldosterone and incorporated less tritiated pregnenolone, progesterone, deoxycorticosterone and corticosterone into aldosterone. Adrenals from rats drinking KCl produced less aldosterone than adrenals from rats drinking sucrose under basal conditions but not under stimulation by ACTH or potassium ions. In both groups, the production of corticosterone and of deoxycorticosterone was the same under various test conditions. These results indicate that a high sodium intake inactivates one or both enzymes essential for the conversion of corticosterone to aldosterone, whereas a high potassium intake has no significant effect on these later steps of aldosterone biosynthesis.

Effect of divergent selection for weaning weight on liveweight and wool growth responses to feed intake in Merino ewes

1993 ◽  
Vol 33 (6) ◽  
pp. 699 ◽  
Author(s):  
RM Herd ◽  
VH Oddy ◽  
GJ Lee
Keyword(s):  
Organic Matter ◽  
Feed Intake ◽  
Divergent Selection ◽  
Growth Responses ◽  
Weaning Weight ◽  
Wool Growth ◽  
Digestible Organic Matter ◽  
Selection For ◽  
Response To Change

During a 6-week experiment, the feed requirements for maintenance of liveweight (LW) by adult Merino ewes were measured in 2 flocks selected over 32 years for divergent weaning weight. Also examined were the net efficiency of LW gain and wool growth in response to change in feed intake, and the ability to digest dietary organic matter. Ewes selected for high weaning weight (W+) were 31% heavier than those selected for low weaning weight (W-) at the start of the experiment. To maintain LW, W+ ewes ate 24% more digestible organic matter (DOM) per day than W- ewes. There were no differences (P>0.2) in the net efficiency of feed use for LW gain. The W+ ewes digested more (P<0.01) dietary organic matter, by 1.8 percentage units, than W- ewes and, consequently, required only 22% more dry feed to maintain their heavier LW. Ewes from the 2 flocks did not differ (P>0.4) in the amount of wool grown, and as W+ ewes were larger, they produced less (P<0.01) wool per kg LW for the same DOM intake.

scholarly journals Changes in the Membrane Permeability of Frog's Sartorius Muscle Fibers in Ca-Free EDTA Solution

1963 ◽  
Vol 47 (2) ◽  
pp. 379-392 ◽  
Author(s):  
H. Kimizuka ◽  
K. Koketsu
Keyword(s):  
Membrane Permeability ◽  
Chloride Content ◽  
Chloride Ions ◽  
Sartorius Muscle ◽  
Constant Field ◽  
Sodium Influx ◽  
Sodium Potassium ◽  
Edta Solution ◽  
Frog Sartorius ◽  
Sodium And Potassium

The changes in the membrane permeability to sodium, potassium, and chloride ions as well as the changes in the intracellular concentration of these ions were studied on frog sartorius muscles in Ca-free EDTA solution. It was found that the rate constants for potassium and chloride efflux became almost constant within 10 minutes in the absence of external calcium ions, that for potassium increasing to 1.5 to 2 times normal and that for chloride decreasing about one-half. The sodium influx in Ca-free EDTA solution, between 30 and 40 minutes, was about 4 times that in Ringer's solution. The intracellular sodium and potassium contents did not change appreciably but the intracellular chloride content had increased to about 4 times normal after 40 minutes. By applying the constant field theory to these results, it was concluded that (a) PCl did not change appreciably whereas PK decreased to a level that, in the interval between 10 and 40 minutes, was about one-half normal, (b) PNa increased until between 30 and 40 minutes it was about 8 times normal. The low value of the membrane potential between 30 and 40 minutes was explained in terms of the changes in the membrane permeability and the intracellular ion concentrations. The mechanism for membrane depolarization in this solution was briefly discussed.

Increased Renal Sensitivity to Aldosterone in the Potassium-Loaded Rat

1976 ◽  
Vol 51 (s3) ◽  
pp. 315s-317s
Author(s):  
W. R. Adam ◽  
J. W. Funder
Keyword(s):  
Sodium Intake ◽  
Control Diet ◽  
High Potassium ◽  
High Sodium ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
High K ◽  
And Control

1. The renal response to aldosterone (urinary sodium and potassium excretion) was determined in adrenalectomized rats previously fed either a high potassium diet or a control diet. High K+ rats showed an enhanced response to aldosterone at all doses tested. 2. This enhanced response to aldosterone required the presence of the adrenal glands during the induction period, could be suppressed by a high sodium intake, but could not be induced by a low sodium diet. 3. No difference between high K+ and control rats could be detected in renal mineralocorticoid receptors, assessed by both in vivo and in vitro binding of tritiated aldosterone. 4. The method of the induction, and the mechanism of the enhanced response, remain to be defined.

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