Protein intake and its relationship to urinary calcium excretion in the preruminant lamb

1988 ◽  
Vol 39 (1) ◽  
pp. 79
Author(s):  
DM Walker ◽  
SJ Al-Ali

Preruminant male crossbred lambs, aged 1-2 days at the start of the experiment, were used. Twenty-four lambs were bottle-fed for an experimental period of 21 days in a 4 x 3 factorial experiment (with unequal replications). The sole source of protein in the milk replacers was casein, supplemented with DL-methionine, to supply either 10, 20, 30 or 40% of the total dietary energy as protein. At each protein level there were three levels of Ca to represent 50% (low), 100% (medium) and 200% (high) of the Ca concentration of ewes' milk (taken to be 360 mg MJ-1 gross energy). The Ca:P ratio in all diets was 1.1:l. The daily intake of gross energy was controlled at 1046 kJ kg-0.73. Nitrogen, Ca and P balances were determined during the last seven days of the experiment. There was no significant effect of protein intake, or of Ca intake, on the daily urinary Ca excretion, which was uniformly low (n = 24; mean, 1.67 � 0.25 mg kg-1).

1987 ◽  
Vol 38 (6) ◽  
pp. 1061
Author(s):  
DM Walker ◽  
SJ Al-Ali

Twenty-seven preruminant male crossbred lambs, aged 1-2 days at the start of the experiment, were used. Three lambs were sacrificed on day 1 and selected bones taken for analysis. Twenty-four lambs, in groups of three, were bottle-fed on low-phosphorus milk replacers in a 2 x 4 factorial experiment. The sole source of protein in the diets was whole beef blood, supplemented with L-isoleucine and DL-methionine, to supply either 10 or 25% of the total dietary energy as protein. At each protein level the diets were supplemented with CaCO3 to provide four ratios of Ca:P (0.5:1, 1:1, 2:1 and 10:1). The daily intake of gross energy was controlled at 880 kJ-0.73. Faeces and urine were collected separately each day and bulked during the last seven days of the experiment for the estimation of N, Ca and P. Serum Ca and P concentrations were determined at weekly intervals. The lambs were sacrificed at the end of the experimental period of 21 days and selected bones were taken for analysis. The concentrations of bone ash, Ca and P all decreased significantly when compared with values determined at the start of the experiment. The lambs given the high-protein diets showed significantly greater losses of bone ash, Ca and P, and had lower serum P, but higher serum Ca concentrations, than lambs fed on the low-protein milk replacers, irrespective of the dietary Ca:P ratios. Phosphorus excretions during the last seven days of the experiment were as follows: faecal P (day-1); low-protein group (n = 12), 3.1 � 0.5 mg kg-1; high-protein group (n = 11) , 4.1 � 0.5 mg kg-1; all lambs (n = 23), 3.6 � 0.3 mg kg-1. Urinary P (day-1): low-protein group (n = 12), 0.92 � 0.22 mg kg-1; high-protein group (n = 11) , 0.61 � 0.03 mg kg-1; all lambs (n = 23), 0.77 � 0.12 mg kg-1. Faecal and urinary P excretion was unaffected by variation in the dietary Ca:P ratio.


1987 ◽  
Vol 38 (6) ◽  
pp. 1061
Author(s):  
DM Walker ◽  
SJ Al-Ali

Twenty-seven preruminant male crossbred lambs, aged 1-2 days at the start of the experiment, were used. Three lambs were sacrificed on day 1 and selected bones taken for analysis. Twenty-four lambs, in groups of three, were bottle-fed on low-phosphorus milk replacers in a 2 x 4 factorial experiment. The sole source of protein in the diets was whole beef blood, supplemented with L-isoleucine and DL-methionine, to supply either 10 or 25% of the total dietary energy as protein. At each protein level the diets were supplemented with CaCO3 to provide four ratios of Ca:P (0.5:1, 1:1, 2:1 and 10:1). The daily intake of gross energy was controlled at 880 kJ-0.73. Faeces and urine were collected separately each day and bulked during the last seven days of the experiment for the estimation of N, Ca and P. Serum Ca and P concentrations were determined at weekly intervals. The lambs were sacrificed at the end of the experimental period of 21 days and selected bones were taken for analysis. The concentrations of bone ash, Ca and P all decreased significantly when compared with values determined at the start of the experiment. The lambs given the high-protein diets showed significantly greater losses of bone ash, Ca and P, and had lower serum P, but higher serum Ca concentrations, than lambs fed on the low-protein milk replacers, irrespective of the dietary Ca:P ratios. Phosphorus excretions during the last seven days of the experiment were as follows: faecal P (day-1); low-protein group (n = 12), 3.1 � 0.5 mg kg-1; high-protein group (n = 11) , 4.1 � 0.5 mg kg-1; all lambs (n = 23), 3.6 � 0.3 mg kg-1. Urinary P (day-1): low-protein group (n = 12), 0.92 � 0.22 mg kg-1; high-protein group (n = 11) , 0.61 � 0.03 mg kg-1; all lambs (n = 23), 0.77 � 0.12 mg kg-1. Faecal and urinary P excretion was unaffected by variation in the dietary Ca:P ratio.


1970 ◽  
Vol 21 (6) ◽  
pp. 933 ◽  
Author(s):  
WJ Parr ◽  
P Steele ◽  
B Gabbedy ◽  
MC Nottle

In recent years a series of widespread outbreaks of acute urinary obstruction has occurred in spring in Merino wethers. Animals involved have been grazing oestrogenic strains of subterranean clover at a time when isoflavone concentrations can be expected to be high. Studies have been made on one property on the relationships between these outbreaks, the pasture isoflavone content, and the urinary excretion of phenolic and other constituents by wethers. A trial group of animals was grazed on a dominant sward of the highly oestrogenic Trifolium subterraneum cv. Dinninup during winter and spring. Isoflavone concentrations in the clover reached a peak in early August. However, since the pasture became highly clover-dominant in September and early October the maximum daily intake of isoflavones probably occurred during this period, which also coincided with the occurrence of maximum concentration and maximum daily excretion of total phenols and acid-precipitable material (APM) in the urine. It is suggested that the sediments causing clinical obstructions at this time of the year may be a direct result of increased excretion of phenols. APM showed a highly significant direct relationship with total phenols but its excretion increased at a greater rate than did that of phenols. Urinary calcium excretion also increased at the same time.


1975 ◽  
Vol 26 (4) ◽  
pp. 673 ◽  
Author(s):  
DM Walker ◽  
RD Kirk

Forty-seven crossbred lambs, aged 2–5 days at the start of the experiment, were used in three experiments. In experiment 1 a supplement of DL-methionine significantly increased the nitrogen balances of lambs given low or medium protein milk replacers based on cows' milk proteins. In experiment 2 the optimum level of supplementation of a low protein diet with DL-methionine was determined. Although the nitrogen balances were significantly increased by the supplement, the actual nitrogen balances at equivalent intakes of gross energy and nitrogen were less than those in experiment 1. The low protein diets in the two experiments differed only in the source of carbohydrate: lactose in cxpcrimcnt 1; lactose + glucose in experiment 2. In the final experiment 24 lambs in a 2 x 2 factorial design were fed on low protein diets containing casein as the source of protein, and lactose or glucose as the sole source of carbohydrate, with or without a supplement of DL-methionine. There was no significant effect of the source of carbohydrate on nitrogen balance.


1980 ◽  
Vol 31 (1) ◽  
pp. 133 ◽  
Author(s):  
DD Phillips ◽  
DM Walker

Preruminant male crossbred lambs, aged 2-5 days at the start of the experiment, were fed on milk replacers that contained groundnut protein isolate as the sole source of protein, supplemented with graded levels of L-lysine hydrochloride. A series of 6x 6 change-over designs with 4-day dietary periods was used in experiments 1 and 2, and a conventional 14-day nitrogen balance in experiment 3. Estimates were made of the minimum intake of lysine coincident with the maximum animal response (MIMR)-measured as maximum nitrogen balance (NB) or minimum plasma urea nitrogen (PUN) concentration. In experiment 1 three diets with different protein concentrations (0.11, 0.18 and 0.25 of total energy as protein) were compared at a controlled intake of gross energy (0.88 MJ/day per kg0.73). At each protein concentration the response to six graded levels of L-lysine hydrochloride was measured. In experiment 2 a diet of constant protein energy concentration (0.25) was offered at three different intakes of energy (0.63, 0.88 and 1.13 MJ/day per kg0 73). At each level of energy intake the response to six graded levels of L-lysine hydrochloride was measured. In experiment 3 a milk replacer containing 0.25 protein energy was offered at a constant intake of 0.88 MJ gross energy/day per kg0 73 and, as in the previous experiments, the response to SIX graded levels of L-lysine hydrochloride was measured. The MIMR for lysine (expressed as a percentage of dietary protein) decreased curvilinearly with an increase in protein concentration, but was unaffected by an increase in the intake of energy. Estimates based on PUN were similar to those based on NB, but the errors associated with the estimates were greater at the lowest protein concentration in experiment 1 and at the lowest intake of energy in experiment 2. Estimates of MIMR in experiments 1 and 3 were in close agreement.


1974 ◽  
Vol 54 (3) ◽  
pp. 411-418 ◽  
Author(s):  
A. D. L. GORRILL ◽  
D. M. WALKER

Unrefined rapeseed (Brassica napus) oils which contained 0.4 (Oro), 16.0 (Bronowski) and 39.3% (Target) erucic acid were compared with butter oil as the sole source of fat in milk replacers for lambs. Lambs were fed 210 kcal gross energy/kg body weight0.73 per day for 2 wk, and then were killed to determine effects of the oils on internal organs. Lamb body weight gains were similar on the Oro and butter oil diets (37 vs. 41 g/kg0.73/day), but were less on the Bronowski and Target oil diets (32 and 19 g/kg0.73/day, respectively). Nutrients in the Oro oil diet were highly digestible, but were less than those in butter oil (94 vs. 99% apparent fat digestibility). Lambs fed the Bronowski and Target oil diets digested only 74 and 82% of the fat. Lambs fed the butter, Oro, Bronowski and Target oil diets retained 72, 62, 57 and 48%, respectively, of the nitrogen consumed. Livers from lambs fed the Target oil diet were pale and showed fatty tissue infiltration. Lambs fed the Bronowski and Target oil diets had enlarged thyroid glands. It was concluded that Oro rapeseed oil could effectively replace all or part of animal fats used in lamb milk replacers.


1982 ◽  
Vol 2 (5) ◽  
pp. 569-578 ◽  
Author(s):  
T. Atinmo ◽  
G.O. Taylor ◽  
C.M.F. Mbofung ◽  
J.L. Fajimi ◽  
F.A. Adenaike

1982 ◽  
Vol 33 (1) ◽  
pp. 117
Author(s):  
NM Malouf ◽  
DM Walker

Preruminant male crossbred lambs, aged 2-5 days at the start of the experiment, were fed on milk replacers containing a soybean protein concentrate (as the sole source of protein) to supply 25 % of the total dietary energy as protein. The minimum intake of methionine plus cystine (M+C) that was coincident with maximum nitrogen balance was estimated (mean�s.e.) at 38.5�1.8 mg/100 kJ diet (equivalent to 3.6�0.2 g sulfur amino acids/16 g nitrogen). When the concentration of M+C was raised to this level by supplementation with DL-methionine, the addition of choline chloride, in amounts to give final concentrations varying from approximately one-seventh up to twice the concentration in cows' milk, did not affect nitrogen balance. The maximum replacement value of cystine for methionine (as judged by the effect on nitrogen balance), in milk replacers adequately supplen~ented with choline chloride and sulfur amino acids, was 47% on a weight basis, or 52% when calculated on the basis of moles of sulfur.


1981 ◽  
Vol 32 (5) ◽  
pp. 801
Author(s):  
NM Malouf ◽  
DM Walker

Preruminant male crossbred lambs, aged 2-5 days at the start of the experiment, were given milk replacers containing between 0.25 and 0.29 of the total energy as protein. A comparison of milk replacers containing either soybean isolates or concentrates as the sole source of protein showed that, while the apparent digestibilities of dry matter and nitrogen were significantly higher for diets containing isolates, the efficiencies of retention of the apparently digested nitrogen were significantly higher for the concentrate diets. The net result was no significant difference in nitrogen balance between the diets. The milk replacers were accepted readily by the lambs, and intakes of gross energy of up to three times the maintenance requirement were attained without difficulty. Nitrogen balances of lambs given a milk replacer based on a soybean concentrate were not significantly improved by supplementation of the diet with lysine, in addition to methionine. Similarly, the nitrogen balances of lambs given a soybean isolate-based milk replacer, plus methionine, were unaffected when one of five supplementary amino acids (Lys, Thr, Val, Isol, Leu) was omitted in turn from the diet.


1970 ◽  
Vol 64 (1) ◽  
pp. 65-74 ◽  
Author(s):  
Lars Runeberg ◽  
B.-A. Lamberg ◽  
P. Reissell ◽  
H. Adlercreutz

ABSTRACT The time course of the renal excretion of calcium, magnesium, sodium, and potassium during sodium depletion and the rapid correction of the extracellular volume deficit was studied in normal subjects and in patients with Addison's disease (AD). The decrease in body weight was similar in the two groups, but the haematocrit value increased more in the patients with AD. Sodium depletion suppressed sodium excretion much more efficiently in normal controls than in the AD patients. Calcium excretion was roughly equally depressed in two groups. During sodium loading there was an immediate increase in renal sodium excretion in the patients with AD, whereas the sodium-retaining state generally continued for about one day in the normal controls. Urinary potassium decreased gradually during the first day of sodium loading in the normal controls but not in the AD patients. In the normal subjects calcium excretion remained low during the first day and increased on the second day of sodium loading. In the AD patients there was a gradual increase in urinary calcium during the first day of sodium loading, which did not, however, parallel the changes in urinary sodium content in individual urine samples. Urinary magnesium did not change significantly. It is concluded that the effect of adrenal steroids on renal calcium excretion is of minor importance. They may, however, to some extent induce calcium retention.


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